INTRODUCTION
The Philosophy of the Sciences is one of the leading parts of Comte’s work. No other brings out more clearly the essential differences which distinguish his doctrine from previous systems.
In Comte’s eyes the philosophy of the sciences is inseparable from the philosophy of history and from the theory of progress. For the sciences are great sociological facts and, as such, are subject, in their evolution, to invariable laws. The method of the philosophy of the sciences could therefore only be the positive method, ever like to itself.
Moreover,—and this is an immediate consequence of this first consideration,—the object of the positive philosophy of the sciences is in no way to “explain” what the sciences themselves do not explain. The sciences, as is well known, do not inquire into their data and their principles. They consider them as sufficiently established by the implicit consent of all men, or at least by the universal usage of learned men. The geometer leaves to others the care of speculating upon the essence of space, or upon the a priori character of his definitions. The physicist, if he form an idea of matter for himself, unhesitatingly adopts the one which appears to be the most immediately advantageous, that is to say, the one which is best in accordance with what he knows of its properties and of its laws. He attributes no more value than that of a simple hypothesis to this idea.
Up to the present the business of solving the questions which the scientific man does not examine has belonged to the philosopher—understand by this term the metaphysician. It is for him to seek what matter, time, movement, space, etc., may be “in themselves.” Whether he descends from metaphysics to the positive sciences, or ascends from the latter to metaphysics, he always endeavours to show that such and such a transcendental hypothesis is more in accordance than any other with what we know to-day of the laws of nature. In a word; the philosophy of the sciences has been, in general, an effort to interpret scientific knowledge metaphysically. This explanation remains in respect to such a knowledge an “extrinsic denomination.” It explains but does not touch it.
Now, according to Comte, there are not two forms of knowledge, the one positive and properly speaking scientific the other metaphysical and properly called philosophical. The whole of our real knowledge in the end bears upon special or general facts. There can therefore be no question of a philosophy which should be essentially distinct from positive knowledge. Any attempt to explain by essences, causes, principles or ends, is excluded by the positive method. Metaphysical problems can no longer be set and, in this sense, when they disappear, the philosophy of the sciences disappears with them.
But, on the other hand, as we have already seen, the positive sciences are not self-sufficient. They need to be crowned and ordered by a philosophy. If then a philosophy is indispensable, and if, at the same time, this philosophy must be positive, relative like the sciences themselves, and homogeneous with them, only one solution remains possible. The philosophy of the sciences will consist in substituting the point of view of the whole to that of the parts. It will still be a product of the positive spirit; but in it this spirit from special will have become general; from particular it will have become universal.
This universal character remains common to Comte’s philosophy and to that of his predecessors. But Comte did not understand it as they did. For metaphysicians in general, and still for Kant, universality is the distinctive sign of knowledge which does not come from experience, which is therefore necessary and a priori. Comte, who does not know of any a priori in the Kantian sense, calls that knowledge universal which remains relative, and which is founded upon induction, but which regulates the other forms of knowledge in the order of generality. Thus the principle of laws is universal. The encyclopÆdic laws of phenomena are universal. The point of view of humanity is universal, because from this point of view a synthesis of the whole of our knowledge is possible. And, as universality is a relative thing, we conceive universalities of different orders.
Henceforth the philosophy of the sciences is easily defined. Are we concerned with a certain science considered by itself? The philosophy of this science consists in embracing at a glance the whole, the object and the method, as opposed to the special point of view of the scientific man who follows the discovery of more or less special laws in a branch of this science, but such a philosophy necessarily remains imperfect and fragmentary. The philosophy of a science is only really established in the general philosophy of the sciences, that is to say by a view at once synthetic and single of all the sciences, in which are co-ordinated the objects which they study, the laws which they discover, the methods which they make use of, and the ends which they should pursue.
It has been said that this is not a philosophy of the sciences but simply a “synthesis of the most general results of the positive sciences.” Comte partly accepts and partly rejects the objection. If he is reproached with not having constructed a philosophy of the sciences according to the old spirit, that is to say an effort at “explanation,” which goes beyond the point of view of positive science, he grants the objection. He considers all philosophy of this kind as out of the question. Is it said that there is no difference between his point of view and that of the scientific man properly so called, unless it be that he successively goes through all the fundamental sciences? Comte calls our attention to the fact that it is not enough to place these sciences side by side to obtain their philosophy. A new point of view, truly universal, although always relative, is needed. How could Comte have distinguished otherwise, in each science, what is lasting and in conformity with the positive spirit from what is decaying and still bears the mark of the theological and metaphysical spirit? Could he especially have fixed the relations which the sciences should maintain among themselves, and could he have imposed upon them a discipline whose principle was not to be found in any one of them?
Thus, until Auguste Comte’s time, the philosophy of the sciences had been a metaphysical conception, joined more or less closely to the whole of positive knowledge. Comte endeavoured to form a conception of this whole, which should be philosophical while remaining positive. It is this conception which is especially set forth in the three first volumes of the Cours de philosophie positive. From the static point of view it is founded upon the hierarchy of the sciences, the unity of the method, and the homogeneity of knowledge. From the dynamic point of view, it endeavours to show the progressive convergence of all the sciences towards sociology, the final and universal science. With this “guiding thread,” Comte will be able to establish in turn the philosophy of each fundamental science, without ever losing sight of the relation which it bears to the whole of the others.
CHAPTER I
MATHEMATICS
In the eyes of philosophers, mathematics has always occupied a privileged place among the sciences. Plato located their object in an intermediate region between the world of sensible phenomena and that of intelligible realities. On the one hand mathematical objects, and in particular the geometrical figures, appeal to the imagination as sensible things; on the other hand, mathematical truths like ideas and the relations between ideas, are characterised by immutable and eternal fixity. This is why the study of mathematics is an excellent preparation for philosophy, which is the science of ideas. While still leaving to the mind the help of direct sensible perception, it accustoms it to permanent truth. During the whole of antiquity the science of mathematics, as the name indicates, was pre-eminently the science. The science of physics, less sure of its object and of its method, was hardly distinguished from philosophical speculation, and lent itself with difficulty to the purely scientific form.
For Plato then, and for those who followed him, mathematics has characteristics which distinguish it from the study of phenomena. In a certain measure, it partakes of the nature of science, conceived as bearing upon what is, upon the absolute reality which is neither subject to change nor to motion. It is true that they start from definitions and hypotheses. But, once the principles are established, they are developed a priori by a succession of necessary demonstrations like the dialectics of ideas.
This conception offers a mixture of metaphysical and positive elements. It implies that the object of science is reality such as it is in itself; but, at the same time, it sees in the demonstration the essential character of science. A long evolution, which culminates in Comte’s doctrine, has driven the metaphysical elements out of science while the other elements subsist in it still. Far from saying with Plato or with his successors that there is no science of the phenomenon or of that which passes away, Comte thinks on the contrary, that the only object of science is phenomenal reality so far as it is subject to laws. Science has not to search for causes or substances; it suffices for it to determine invariable relations.
If the mathematical sciences have long been the only sciences properly so called, and if to-day they are still more advanced than any others, it is because the geometrical and mechanical phenomena are indeed the simplest of all, and those which are most naturally connected among themselves. The period during which they could be studied by observation could therefore be very short, so short that it is even not absurd to maintain that it never existed, and that, in this case, rational knowledge was not preceded by the empirical establishment of facts. But the difference between mathematics and the other sciences none the less remains one of degree and not of kind. The Science of Mathematics is in advance of the other sciences; but all work on common ground. In a word, like all other sciences it is a natural science.
This endeavour to present the whole of the sciences as homogeneous, that is to say, to avoid two distinct classes being formed of mathematics on the one hand, and of the sciences of nature on the other, had already been attempted before Comte. This endeavour imposed itself, so to speak, upon modern philosophers, from the time when Descartes sought for a universal method for science conceived as a whole. Comte, who saw very well the defect in the Cartesian conception, in which the ascendency of mathematics was still too much felt, did not, however, deny that his own conception proceeded from that of Descartes. In another form, the idea of the homogeneity of the sciences is also found in Leibnitz and even in Kant. Does not the Critique de la raison pure show that mathematics on the one hand, and physics on the other, equally rest upon principles which are synthetic a priori? In the ProlÉgomenes À toute mÉtaphysique future just as the chapter corresponding to l’esthÉtique transcendentale is entitled “How are pure mathematics possible a priori?” so the chapter corresponding to the Logique transcendentale bears as its title “How are pure physics possible a priori?” On another plan Comte’s theory is parallel to Kant’s. Here as there mathematics as well as physics rests upon synthetic principles—“superior to experience,” says Kant—proceeding from experience, says Comte. The latter, it is true, did not know Kant’s theory, and, had he known it he would not have accepted it. But the analogy of tendency subsists none the less beneath the diversity of doctrines.
The immediate antecedent of Comte’s theory is found in d’Alembert. The author of the Discours prÉliminaire had said, “We will divide the science of nature into physics and mathematics.”
II.
Every science has its origin in the art corresponding to it. Mathematics arose out of the art of measuring magnitudes. Indeed this art would be very rudimentary if we only practised direct measurement. Among the magnitudes which interest us there are very few which we can measure thus. Consequently the human mind had to seek some indirect way of determining magnitudes.
In order to know the magnitudes which do not allow of direct measurement, we must evidently connect them with others which are capable of being immediately determined, and according to which we succeed in discovering the former, by means of the relations which exist between them and the latter. “Such is the precise object of mathematical science in its entirety.”102 We see immediately how extremely vast it is. If we must insert a large number of intermediaries between the quantities which we desire to know, and those which we can measure immediately, the operations may become very complicated.
Fundamentally, according to Comte, there is no question, whatever it may be, which cannot be finally conceived as consisting in determining one quantity by another, and consequently which does not depend ultimately upon mathematics. It will be said that we must take into account not only the quantity, but also the quality of the phenomena. This objection, decisive in the eyes of Aristotle, who could not conceive that we could legitimately [Greek: metaballein] [Greek: eis allo genos], no longer holds good for modern thinkers. Since Descartes’ time, they have seen analysis applied to geometrical, mechanical and physical phenomena. There is no absurdity in conceiving that what has been done for these phenomena is possible for the others. We must be able to represent every relation between any phenomena whatever by an equation, allowing for the difficulty of finding this equation and of solving it.103 As a matter of fact, we are quickly stopped by the complexity of the data. In the present state of the human mind there are only two great categories of phenomena of which we regularly know the equations: these are geometry and mechanics.
This being established, the whole of mathematical science is divided into two parts: abstract and concrete mathematics. The one studies the laws of geometrical and mechanical phenomena. The other is constituted by the calculus, which, if we take this word in its largest sense, applies to the most sublime combinations of transcendent analysis, as well as to the simplest numerical operations. It is purely “instrumental.” Fundamentally, it is nothing else than an “immense admirable extension of natural logic to a certain order of deductions.”
This part of mathematical science is independent of the nature of the objects which it examines, and only bears upon the numerical relations which they present. Consequently, it may happen that the same relations may exist among a great number of different phenomena. Notwithstanding their extreme diversity these phenomena will be considered by the mathematician as presenting a single analytical question, which can be solved once for all. “Thus, for instance, the same law which reigns between space and time when we examine the vertical fall of a body in vacuo, is found again for other phenomena which present no analogy with the former nor among themselves; for it also expresses the relation between the area of a sphere and the length of its diameters; it equally determines the decrease in intensity of light or of heat by reason of the distance of the objects lighted and heated, etc.”104 We have no general method which serves indifferently for establishing the equations of any natural phenomena whatever: we need special methods for the several classes of geometrical, optical, mechanical phenomena, etc. But, whatever may be these phenomena, once the equation is established, the method for solving it is uniform. In this sense, abstract mathematics is really an “organon.”
Geometry and mechanics, on the contrary, should be regarded as real natural sciences, resting as the others do upon observation. But, adds Comte, these two sciences present this peculiarity, that in the present state of the human mind, they are already used, and will continue to be used as methods far more than as direct doctrine. In this way mathematics is in fact “instrumental,” not only in abstract parts, but also in its relatively concrete parts. It is entirely used as a “tool” by the more complicated sciences, such as astronomy and physics. It is truly the real logic of our age.
In the philosophical study of abstract mathematics, Comte proceeds successively from arithmetical to algebraical calculation, and from the latter to the transcendent analysis or differential and integral calculus. After having stated the manner in which this calculus is presented according to Leibnitz and to Newton, he adopts that of Lagrange, which appears to him the most satisfactory. It is true that at the end of his life his admiration for the author of the MÉcanique analytique had greatly diminished. Without here entering into the detail of questions, we will limit ourselves to the indication of a consideration upon the bearings of abstract mathematics, which appears to be of capital importance to Comte. Whether it be a question of ordinary analysis, or especially of transcendental analysis, Comte brings out at once the extreme imperfection of our knowledge, and the extraordinary fecundity of their applications. He can only solve a very small part of the questions which come before us in these sciences. However, “in the same way as in ordinary analysis we have succeeded in utilising to an immense degree a very small amount of fundamental knowledge upon the solution of equations, so, however little advanced geometers may be up to the present time in the science of integrations, they have none the less drawn, from these very few abstract notions the solution of a multitude of questions of the first importance, in geometry, in mechanics, in thermology, etc., etc.”105 The reason of this is that the least abstract knowledge naturally corresponds to a quantity of concrete researches. The most powerful extension of intellectual means which man has at his disposal for the knowledge of nature consists in his rising to the conception of more and more abstract ideas, which are nevertheless positive. When our knowledge is abstract without being positive, it is “fictitious” or “metaphysical.” When it is positive without being abstract, it lacks generality, and does not become rational. But when, without ceasing to be positive, it can reach to a high degree of abstraction, at the same time it attains the generality, and, along the lines of its furthest extension, the unity which are the end of science.
Hence the importance of Descartes’ fine mathematical discovery, and also of the invention of differential and integral calculus, which may be considered as the complement to Descartes’ fundamental idea concerning the general analytical representation of natural phenomena. It is only, says Comte, since the invention of the calculus, that Descartes’ discovery has been understood and applied to the whole of its extent. Not only does this calculus procure an “admirable facility” for the search after the natural laws of all the phenomena; but, thanks to their extreme generality, the differential formulÆ can express each determined phenomenon in a single equation, however varied the subjects may be in which it is considered. Thus, a single differential equation gives the tangents of all curves, another expresses the mathematical law of every variety in motion, etc.
Infinitesimal analysis, especially in the conception of Leibnitz, has therefore not only furnished a general process for the indirect formation of equations which it would have been impossible to discover directly, but in the eyes of the philosopher it has another and a no less precious advantage. It has allowed us to consider, in the mathematical study of natural phenomena, a new order of more general laws. These laws are constantly the same for each phenomenon, in whatever objects we study it, and only change when passing from one phenomenon to another “where we have been able moreover, in comparing these variations, to rise sometimes, by a still more general view, to a positive comparison between several classes of various phenomena, according to the analogies presented by the differential expressions of their mathematical laws.”106 Comte cannot contemplate this immense range of transcendent analysis without enthusiasm. He calls it “the highest thought to which the human mind has attained up to the present time.” The highest, because being the most profoundly abstract among all the positive notions, this thought reduces the most comprehensive range of concrete phenomena to rational unity.
As the consideration of analytical geometry suggested to Descartes the idea of “universal mathematics,” which lies at the basis of his method, so we can think that philosophical reflection upon transcendental analysis led Comte to the idea of those “encyclopÆdic laws,” which hold such an important place in his general theory of nature. For these encyclopÆdic laws, analogous as they are to the differential formulÆ spoken of by Comte, are equally verifiable in orders of otherwise irreducible phenomena, and allow us to conceive them as convergent.
III.
Geometry is the first portion of concrete mathematics. Undoubtedly the facts with which it deals are more connected among themselves than the facts studied by the other sciences, and this allows us easily to deduce some of these facts once the others are given. But there is a certain number of primary phenomena which, not being established by any reasoning, can only be founded upon observation, and which stand as the basis of all geometrical deductions.107 Although very small, this part of observation is indispensable because it is the initial one, and never can quite vanish.
In this way, metaphysical discussions upon the origin of geometrical definitions and space are set aside. Comte here adopts d’Alembert’s opinion. The latter had said: “The true principles of the sciences are simple recognised facts, which do not suppose any others, and which consequently can neither be explained nor questioned: in geometry they are the properties of extension as apprehended by sense. Upon the nature of extension there are notions common to all men, a common point at which all sects are united as it were in spite of themselves, common and simple principles from which unawares they all start. The philosopher will seize upon these common primitive notions to make them the basis of the geometrical truths.”108
Extension is a property of bodies. But, instead of considering this extension in the bodies themselves, we consider it in an indefinite milieu which appears to us to contain all the bodies, of the universe and which we call space. Let us think, for instance, of the impression left by a body in a fluid in which it might be immersed. From the geometrical point of view this impression can quite conveniently be substituted to the body itself. Thus, by a very simple abstraction, we divest matter of all its sensible properties, only to contemplate in a certain manner its phantom, according to d’Alembert’s expression. From that moment we can study not only the geometrical forms realised in nature, but also all those which can be imagined. Geometry assumes a “rational” character.
Similarly, it is by a simple abstraction of the mind that geometry regards lines as having no thickness, and surfaces as being without depth. It suffices to conceive the dimension to be diminished as becoming gradually smaller and smaller until it reaches such a degree of thinness that it can no longer fix the attention. It is thus that we naturally acquire the “real idea” of surface, then of the line, and then of the point. There is therefore no necessity to appeal to the a priori.
Thus constituted, the object of geometry is the measurement of extension. But since this measurement can hardly ever be directly taken by superposition, the aim of geometry is to reduce the comparison of all kinds of extensions, volumes, surfaces or lines to simple comparisons of straight lines, the only ones regarded as capable of being immediately established.”109 The object of geometry is of unlimited extent, for the number of different forms subject to exact definitions is unlimited. In regarding curved lines as generated by the movement of a point subject to a certain law, we can conceive as many curves as laws.
The human mind, in order to cover this immense field, the extension of which it was very late in apprehending, may pursue two different methods. Perfect geometry would, indeed, be the one which would demonstrate all the properties of all imaginable forms, and this can be obtained in two ways. Either we can successively conceive each of the forms, the triangles, the circle, the sphere, the ellipse, etc., and seek for the properties of each one of them. Or else we can group together the corresponding properties of various geometrical forms, in such a way as to study them together, and, so to speak, to know beforehand their application to such and such a form which we have not yet examined. “In a word,” says Comte, “the whole of geometry can be ordered, either in relation to bodies which are being studied, or in relation to phenomena which are to be considered.” The first plan is that of the geometry of the ancients, or special geometry; the second is that of the geometry since Descartes, or general geometry.110
At its origin geometry could only be special. The ancients, for instance, studied the circle, the ellipse, the parabola, etc., endeavouring, in the case of each geometrical form, to add to the number of known properties. But, if this line of advance had been the only one which could be followed, the progress of geometry would never have been a very rapid one. The method invented by Descartes has transformed this science, by enabling it to become general, and to abandon the individual study of geometrical forms for the common study of their properties. This revolution has not always been well understood. Often in teaching mathematics, its bearings are not sufficiently shown. From the manner in which it is usually presented, this “admirable method” would at first seem to have no other end than the simplification of the study of conic sections or of some other curves, always considered one by one according to the spirit of ancient geometry. This would not be of great importance. The distinctive character of our modern geometry consists in studying in a general way the various questions relating to any lines or surfaces whatever by transforming geometrical considerations and researches into analytical considerations and researches.111
All geometrical ideas necessarily relate to the three universal categories; magnitude, form, position. Magnitude already belongs to the domain of quantity. Form can be reduced to position, since every form can be considered as the result of the advance of a point, that is to say of its successive positions. The problem is therefore to bring all ideas of situation whatever back to ideas of magnitude. How did Descartes solve it? By generalising a process which we may say is natural to the human mind, since it comes spontaneously into being under the stress of necessity. Indeed, if we must indicate the situation of an object without showing it immediately, do we not refer it to others which are known, by stating the magnitude of geometrical elements by which we conceive the object to be connected with them? Geographers act in the same way in their science to determine the longitude and latitude of a place, and astronomers to determine the right ascension and the declination of a star. These geographical and astronomical co-ordinates fulfil the same office as the Cartesian co-ordinates. The only difference, but it is a capital one, consists in the fact that Descartes carried this method to the highest degree of abstract generality thus giving it its maximum of fertility and power.
Although general geometry is infinitely superior to special geometry it cannot, nevertheless, altogether dispense with the latter. As the ancients did, so it will always be necessary to begin with special geometry. For general geometry rests upon the use of calculation. But if, as Comte has said, geometry is truly a science of facts calculation will evidently never be able to supply us with the first knowledge of these facts. In order to lay the foundations of a natural science simple mathematical analysis would never suffice, nor could it give a fresh demonstration of it, when these foundations have already been laid. Before all things a direct study of the subject is necessary, until the precise relations are discovered. “The application of mathematical analysis can never begin any science whatever, since it could never take place except when the science has been sufficiently elaborated to establish, in relation to the phenomena under consideration, some equations which might serve as a starting-point for analytical work.”112 In a word, the creation of analytical geometry does not prevent geometry from remaining a natural science. Even when it has become as purely rational as possible, it none the less remains rooted in experience.
IV.
The second part of concrete mathematics (mechanics) is also one of the natural sciences which owes its marvellous progress to analysis. Here again we must distinguish the data which are at the basis of science, and which are facts, from the abstract development undergone by this science because of the simplicity of these facts and the precision of the relations which exist between them. The distinction between what is “really physical” and what is “purely logical”113 is not always an easy one. We must, however, separate facts furnished by experience, from artificial conceptions whose object is to facilitate the establishment of general laws of equilibrium and of motion.
Only to consider inertia in bodies is a fiction of this kind. Physically the force of inertia does not exist. Nature nowhere shows us bodies which are devoid of internal activity. We term those which are not alive inorganic, but not inert. Were gravitation alone common to all molecules, it would suffice to prevent the conception of matter as devoid of force. Nevertheless, mechanics only considers the inertia of bodies. Why? Because this abstraction presents many advantages for the study, “without, moreover, offering disadvantages in the application.” Indeed, if mechanics had to take into account the internal forces of bodies and the variations of these forces, the complications would immediately become such that the facts could never be submitted to calculation. Mechanics would run the risk of losing its character as a mathematical science. And, on the other hand, as it only considers the movements in themselves, regardless of their mode of production, it is always lawful for mechanics to replace, if necessary, the internal forces by an equivalent external force” applied to the body. The inertia of matter is therefore an abstraction, the end of which is to secure the perfect homogeneity of mechanical science, by allowing us to consider all moving bodies as identical in kind, and all forces as of the same nature.
The “physical” character of this science is again evident from the consideration of the three fundamental laws upon which it rests.114
The first, called Kepler’s law, is thus defined: “All movement is naturally rectilinear and uniform; that is to say, any body subject to the action of a single force which acts upon it instantaneously, moves constantly in a straight line with invariable speed.” It has been said that this law is derived from the principle of sufficient reason. The body must continue in a straight line because there is no reason why it should deviate from it more on one side than on the other. But, answers Comte, how do we know that there is no reason for the body to deviate, except precisely because we see that it does not deviate? The reasoning “reduces itself to the repetition in abstract terms of the fact itself, and to saying that bodies have a natural tendency to move in a straight line, which is precisely the proposition which we have to establish.” It is by similar arguments that the philosophers of antiquity, and especially Aristotle, had, on the contrary been led to regard circular motion as natural to the stars, in that it is the most perfect of all, a conception which is only the abstract enunciation of a imperfectly analysed phenomenon. The tendency of bodies to move in a straight line with constant speed is known to us by experience.
The second fundamental law of mechanics, called Newton’s law, expresses the constant equality of action and reaction. It is pretty generally agreed to-day to consider this law as resulting from the observation of facts. Newton himself understood it so.
Finally the third law establishes that “every movement exactly possessed in common by all the bodies of any system does not alter the particular movements of those different bodies in respect to each other; but those movements continue to take place as if the whole of the system was motionless.” This law “of the independence or of the coexistence of movements” was formulated by Galileo. It is no more a priori than the two preceding ones. How could we be sure, if experience did not show it to us, that a common motion communicated to a system of bodies moving in relation to one another, would change nothing in their particular motions? When his law was made known by Galileo, on all hands there arose a cloud of objections, tending to prove a priori that this proposition was false and absurd. It was only admitted later when, in order to examine it, the logical point of view was set aside for the physical point of view. It was then seen that experience always confirmed this law, and that, if it ceased to operate, the whole economy of the universe would be thrown into utter confusion. For instance, the movement of the translation of the earth in no way affects the mechanical phenomena which take place upon the surface or within the globe. As the law of the independence of motions was unknown when the theory of Copernicus appeared, an objection was put to him which was thought to be drawn from experience. He was told that if the earth moved round the sun all the movements which take place upon it or within it would be modified by the action. Later on when Galileo’s law became known, the fact was explained and the objection disappeared.
Once these three laws are established, mechanics has sufficient foundation. Henceforth the scientific edifice can be constructed by simple logical operations, and without any further reference to the external world. But this purely rational development no more transforms mechanics into an a priori science than the application of analysis deprives geometry of its character as a natural science. What proves this, in one case as in the other, is the possibility of passing from the abstract to the concrete and of applying the results obtained to real cases, merely restoring the elements which science had been compelled to set aside. If it were possible entirely to constitute the science of mechanics according to simple analytical conceptions, we could not imagine how such a science could ever become applicable to the effective study of nature. What guarantees the reality of rational mechanics is precisely its being founded upon some general facts, in a word, upon the data of experience.
Comte could assuredly not foresee the controversies which to-day bear upon the principles of mechanics and which have been summed up by Mr. PoincarÉ in an article upon Hertz’s mechanical theories.115 Mr. PoincarÉ says that the principles of Dynamics have been stated in many ways, but nobody sufficiently distinguished between what is definition, what is experimental truth, and what is mathematical theorem. Mr. PoincarÉ is satisfied neither with the “classical” conception of mechanics, whose insufficiency has been shown by Hertz, nor with the conception with which Hertz wishes to replace it. In any case it is a high philosophical lesson to see the classical system of analytical mechanics—a system constructed with such admirable accuracy, and made by Laplace to arise altogether, as Comte says, out of a single fundamental law,—to see it after a century labouring under grave difficulties, not unconnected with the progress of physics.
Might not this be an argument in support of the theory of d’Alembert and of Comte on the nature of concrete mathematics? Geometry and mechanics would only differ from the other natural sciences by the precision of the relations between the phenomena of which they treat, by the facility which they have for dealing with these relations by means of calculus and analysis, and, consequently, by assuming an entirely rational and deductive form. For the extraordinary power of the instrument should not hide from us the nature of the sciences which make use of it. These, like the others, bear upon natural phenomena. Only, as these phenomena are the most simple, the most general and the most closely allied of all, these sciences are also those which respond in the best way to the positive definition of science. They have “very easily and very quickly replaced empirical statement by rational prevision.” They are composed of laws and not of facts. But, conforming in this again to the positive definition of science, they are empirical in their origin, and they remain relative in the course of their development.
Thus positive philosophy, having reached the full consciousness of itself, reacts upon the conception of the sciences which have most contributed to its formation. When the philosophy is universally accepted the idea that a science can be a priori, that is both absolute and immutable, will have disappeared. Precisely because it is the most perfect type of a positive science, mathematics will no longer claim these characteristics, and its ancient connection with metaphysics will be finally severed.
CHAPTER II
ASTRONOMY
The object of astronomy is the discovery of the laws of the geometrical and mechanical phenomena presented by the celestial bodies; and, by the knowledge of these laws to obtain the precise and rational prevision of the state of our system at any given period whatever. It is in a word, “the application of mathematics to celestial phenomena.”116
Mr. H. Spencer has taken occasion of this definition to criticise the place assigned by Comte to astronomy in his classification of the sciences. He makes him contradict himself. He says: you term fundamental sciences the abstract sciences which do not study beings in nature, but the laws which govern phenomena in those beings; by what right is astronomy placed among these sciences, between mathematics and physics? Is not the object of astronomy the study of certain beings in nature? In what does the application of mathematics to celestial phenomena differ from their application to other cases? It appears evident that here Comte introduces into the series of abstract sciences a science which is really concrete, or at least, according to Mr. Spencer’s expression, abstract-concrete.
Comte had foreseen the objection. The answer which he makes throws a strong light upon the sense in which he understands the words “abstract” and “general” as applied to the sciences. He partly accepts the objection. The true astronomical notions, he says, only differ from purely mathematical notions by their special restriction to the celestial case; and this, at first sight, must appear contrary to the essentially abstract nature of the speculations which belong to the first philosophy. But on the other hand, these speculations bear upon the phenomena given in experience, and the order of the abstract sciences should reproduce the real order of dependence of the phenomena. Thus the first of these sciences, mathematics, determines the essential laws of the most general phenomena, which are common to all material beings (form, position, movement). Now, are not the most general phenomena after these, those “of which the the continuous ascendency inevitably dominates the course of all the other phenomena?”117 In other words, before passing to the study of physical, chemical, biological phenomena, etc., it is indispensable to know the general laws of the milieu in which these phenomena are manifested. Outside of this milieu, they would be impossible, or at any rate, it so conditions them that, were it otherwise, these phenomena would also be different from what they are.
The character of generality which, with that of abstraction, is made use of to institute the hierarchy of phenomena is thus reduced to the idea of dependence. It is the consideration of this dependence which assigns to astronomy its place between mathematics and physics in the encyclopÆdic ladder of the sciences. Considered singly in themselves, the phenomena studied by astronomy are purely geometrical and mechanical. They would not, therefore, constitute the object of a science distinct from mathematics. But positive philosophy considers everything from the point of view of humanity. Now, for humanity, this “special case” is of unequalled importance. All the other phenomena given to us by experience (except the mathematical phenomena) depend, in a more or less direct manner, upon astronomical phenomena. The knowledge of astronomical laws is therefore the necessary condition for the knowledge of all the others. Thus, the infringement of the principle of the hierarchy of fundamental sciences is only apparent. An analogous case is found in chemistry. The analysis of air and water is incorporated in abstract chemistry, because air and water constitutes the general milieu, “in which all ulterior phenomena occur.”118
The place given to astronomy is therefore justified. This science, moreover, remains abstract. For it to be a concrete science, all aspects of the existence of celestial bodies would have to be studied and considered in their relations, to each other in it. But, on the contrary, astronomy only studies the geometrical and mechanical phenomena in the celestial bodies, all physical and chemical considerations, etc., being eliminated. Comte concludes that in passing on to the celestial case mathematics does not lose its abstract nature. It only becomes more developed in the case of a special example, whose extreme importance demands such a specialisation.
The abstract character of astronomy belongs to it almost a priori. The facts upon which it rests are only revealed to us by one of our senses, the most intellectual of them indeed, but by which we are only informed of the mathematical properties of bodies. Our eyes alone touch the stars. There is no astronomy for a blind race. Dark stars, if such there be, are for ever hidden from us. All that is given to us, therefore, is the shape, the position and the motion of visible celestial bodies. We can never by any means know how to study their chemical composition, nor their mineral structure, nor a fortiori the nature of the organic bodies which may live upon them. Comte might have formulated in less categorical terms affirmations which were soon to be contradicted by spectral analysis and by photography. But he was confirmed in the entirely abstract and mathematical conception which he had of astronomy by his persuasion that no discoveries of so far-reaching a nature were possible.
Thus, astronomy appeared to be an excellent type of a positive science, because it is at once natural and abstract, and in it these two characteristics are equally apparent, which was not the case in mathematics. In this science the share of observation is so limited, so transient, that it becomes inappreciable. In astronomy, on the contrary, determination of certain facts evidently plays a part in the science. But, at the same time, nowhere do we see more clearly that science does not consist in the mere apprehension of facts. Here they are so simple, and moreover so uninteresting, that their connexion and the knowledge of their laws alone deserves the name of science. In general, what is an astronomical fact? None other than this: such a star has been seen at such a precise instant, and under such an angle duly measured. The more or less profound elaboration of these observations is indispensable to science, even in its most imperfect state. Astronomy, says Comte, did not really come into being when the priests of Egypt or Chaldea made a series of more or less exact empirical observations in the heavens; but only when the first Greek philosophers began to reduce the general phenomenon of diurnal motion to a few geometrical laws.119
Of all the natural sciences, after mathematics, astronomy is also the most perfectly free from all theological and metaphysical considerations. From every point of view it is positive. Astronomers no longer have recourse to a Providence, which as the intelligent cause of the order of the celestial world, would in its turn, witness to the existence of this cause. They do not inquire any more into the intimate nature of forces (gravitation, attraction, etc.). Astronomy is content to determine the invariable relations of phenomena with the greatest possible precision. It is here that philosophical minds can study the essential characteristics of a positive science. In it they will also see how disinterested it must be in order to become useful. “Without the highest speculations of geometers upon celestial mechanics, which have so greatly increased the precision of astronomical tables, it would be impossible to determine the longitude of a ship with the degree of accuracy which is now attainable.”120
Finally no science has exercised a greater influence upon the evolution of the human mind than this one. The great epochs in astronomy are also those in cosmological philosophy. The desperate resistance which was offered by theological dogmatism to Galileo’s discovery responded to a just apprehension of the consequences involved in this discovery. To admit that the earth was not the centre of the world was to take a first and a decisive step in the way which leads away from the anthropocentric prejudice. It was like pledging oneself to substitute sooner or later the relative point of view to the absolute one in philosophy. It was introducing the positive spirit, to-day in speculative physics, to-morrow in speculative ethics.
II.
Although astronomy is an “eminently mathematical” science, the method of working by observation is used in it. The astronomer observes before calculating, and he observes again after having calculated. The art of observation for which there is no use in mathematics appears here then, and, with it, the inductive method.
Indeed there is no “absolute separation” between observing and reasoning.121 The mind does not first observe facts in a receptive or “passive” manner, in order to work out combinations of these facts afterwards. In reality every observation is a combination, and this is particularly true in astronomical observation. The facts which we observe are really constructed. We can only see simultaneous or successive directions, according to which the mind must construct the form or the movement which the eye could not take in. The necessary and constant association “between prevision and inspection” is more intimate and more evident here than in any other science.
In the same way, hypothesis (which is inseparable from observation) can be studied in astronomy in its most simple form. Here it is presented in its clearest aspect, and, if one may say so, in the one which most reveals its essential nature. Now, hypothesis in astronomy “serves to fill up the necessary gaps in observation.” It provisionally supplements the knowledge—not indeed of causes, for positive science seeks nothing of this kind—but of facts and laws which we ignore. For instance, the simple geometrical sketch of a diurnal motion would remain impossible without an abstract hypothesis which being compared with the concrete spectacle presented by the movement itself enables us to connect together the various celestial positions. Modern astronomy, which has destroyed primitive assumptions regarded as real laws of the world, has maintained their permanent value for conveniently representing phenomena provisionally. And, as we are not deceived as to the reality of such assumptions we can use without scruple any one which seems to us most advantageous.122
The use of hypothesis, as it is employed in astronomy, must be carried into the other sciences. This mode of procedure everywhere remains like to itself, although we do not always conceive it so clearly. “Its normal domain coincides with that of observation.” An hypothesis completes by anticipation what we know of facts and of their laws. Consequently, it is subject to be modified, corrected, or contradicted by a wider or deeper knowledge of facts. Hypotheses then are only valid during the time when they are advantageous, that is to say, as long as they serve to unite and co-ordinate our observations. As has been said, they labour to render themselves useless. But they are indispensable, and science, without them, could neither advance nor even begin. Far from giving too small a share to hypothesis, like Bacon, Comte would rather incur the reproof of having given it too large a one. He made too much use of it himself at the end of his life. But the theory which he gave of it in the Cours de philosophie positive and of which certain features appeal again in Claude Bernard’s Introduction a l’Étude de la mÉdecine experimÉntale, was a careful study of its nature and function.
III.
Astronomy, or at least that part of astronomy which bears the name of celestial mechanics, of all the physical sciences is the one which has been carried to the highest degree of perfection. Nowhere else have the phenomena been better reduced to a supreme law which allows us to foresee them with sufficient precision. But this result could only have been obtained by substituting the notion of a solar world to that of a universe.123 This world is the only one which we can comprehend as a system. If the object of astronomy were the general laws of the universe, this science would be extraordinarily imperfect, not to say impossible. For what do we know about cosmic laws?124 We do not even know whether Newton’s law applies to any or all systems of stars.
We must then distinguish between astronomy as the science of our world and sidereal astronomy. The latter is not absolutely forbidden us, but we know very little on this subject, and we shall probably never know much more. Do the innumerable suns scattered in space form a general system, or do independent systems exist? Is space limitless? Is the number of celestial bodies an infinite one? philosophers ask. In truth the consideration of our world is positive. The consideration of the universe is not.
History helps us to understand the transition which led from one to the other. Ancient philosophy made the earth the centre of the universe. Notwithstanding the diversity of their particular characteristics and of their motions, it was natural then for all the celestial bodies to be conceived as the parts of a single system. A more or less clearly expressed postulate supported this astronomical conception: the purpose of the universe was the existence of man. There was no occasion to distinguish our world from the whole world. But could this conception stand when the earth was reduced to the condition of a planet revolving round a sun so like a multitude of other suns. Suddenly the stars were carried to distances infinitely more considerable than the greatest planetary intervals. Undoubtedly the human mind could continue to regard the very small groups of which the earth forms a part as a system. But the system (if it exists) which embraces the whole of the celestial bodies ceased henceforth to be within our reach. Since then “the notion of the world has become clear and habitual, and that of the universe has become uncertain and almost unintelligible.”125
It matters little, moreover, for, according to one of Comte’s favourite maxims, what we have no means of knowing, neither have we any need to know; and every thing which it is our interest to learn we can also attain. Nor should we see in this any providential harmony. That which it is our interest to know must always in some way influence the conditions of our existence. By the mere fact that this action makes itself felt, it is inevitable that sooner or later, directly or indirectly, we should come to know of it. This reflection can be well applied to astronomy. The study of the laws of the solar system, of which we form a part, is of supreme interest for us: and we have reached very great precision on this point. On the contrary, the exact notion of the universe is inaccessible to us; but it is unimportant to us leaving out of the question our “insatiable curiosity.” The independence of our world is certain. The phenomena which take place within the solar system do not appear to be affected by the more general phenomena which relate to the mutual action of suns. Our tables of celestial events, drawn up long beforehand and taking into consideration no other world than our own, so far accord strictly with direct observations. Supposing the law of gravitation to extend to the entire universe, the perturbation in our world caused by a mass equal to a million times its own, and which would be situated at the distance of the nearest sun to our own, would be several thousand million times less than that which brings about our tides, that is to say practically nil.
Here, says Comte, is the only exception to the encyclopÆdic law according to which the more general phenomena control the more particular ones without being influenced by them.126 From this he simply concludes that the phenomena of our system are the most general to which positive research can extend, and that the study of the universe must henceforth be excluded from natural philosophy. The encyclopÆdic law then remains true for the whole of positive philosophy.
The delimitation of the object of astronomy is one of the points where we can best follow the successive modifications of Comte’s thought. In the second volume of the Cours de philosophie positive he gave to astronomy the place which is generally conceded to it by scientific men. He even claims, as a condition for its utility, the most perfect disinterestedness of scientific research in the whole extent of its province. The example which he gives of it (the determination of longitude at sea), is borrowed from Condorcet. Undoubtedly, Comte already insists upon the distinction between the ideas of world and universe, the former only being positive. Nevertheless, he still admits that we should not give up all hope of obtaining some sidereal knowledge,127 and that it would be very precious for us to know the relative motions of multiple stars, etc. But already in the sixth volume of the Cours he condemns entirely the “so-called sidereal astronomy, which to-day constitutes the only grave scientific aberration peculiar to celestial studies.”128 Ten years later, in the first volume of the Politique positive, he “regenerates” astronomy from the synthetic point of view. He is no longer content to limit it to the knowledge of the solar system. He confines the particular study of our world within narrow limits. Astronomy, like the other sciences, from objective must become subjective. Instead of the vague (that is to say indefinite) study of the heavens its end must be the knowledge of the earth, and the consideration of the other celestial bodies only in their relation to the human planet. At this price alone can the unity of this science be secured.129
Thus Comte came back to Aristotle’s closed world with the earth as its centre. He points it out himself in showing in what way he differs from the ancient conception. “This unity,” he says, “existed for the ancients, but was of an absolute character which at that time was legitimate.” When the motion of our planet became known, the ancient constitution of celestial science might merely have been modified “by preserving in it, as subjective, the centre which was at first supposed to be objective.” That would have sufficed to change astronomy from an absolute science to a relative one. Undoubtedly the ancients were deceived in believing the earth to be the centre of the world; but, in order to correct their error, it sufficed to say, the centre of our world. The subjective synthesis “indeed concentrates the celestial studies round the earth.” The other stars only deserve our attention in so far as the knowledge of our planet requires it. Comte ends by saying in the fourth volume of the Politique positive that, strictly speaking, the study of the sun and moon would suffice. We may add to them the ancient planets, but not the “little telescopic planets.”130
This progressive narrowing of the astronomical domain does not indicate a radical change in Comte’s philosophical thought. It only results from the growing subordination of the scientific interest to other superior interests. To know for the sake of knowing, appears to Comte to be a wrong use of the human intellect. The Newtons and the Laplaces in the past have fulfilled a necessary function, and humanity owes them eternal gratitude. They struck a decisive blow against theological and metaphysical philosophy; and secured the victory for the positive spirit. In their time scientific speculation which tended to the discovery of the laws of phenomena, and especially of celestial phenomena, was at once the most sublime and the most useful occupation which those men of genius could set themselves. But now that their efforts have culminated in the foundation of positive philosophy, and this philosophy itself in the “final religion,” there is no longer any reason to continue researches with which henceforth humanity can dispense. We must even “cut down many idle acquisitions.”131 In a word, from the religious point of view, Comte, in order to remedy the anarchy of science, suppresses its liberty.
These extreme, but logically deduced consequences, are part of the whole of Comte’s religious conceptions, that is to say of a distant ideal. They must not blind us to the profundity of his philosophical considerations on astronomy. His reflections upon the relation between the ideas of the world and of the universe correspond, from the positive point of view, to the first antinomy of the transcendental Dialectics in the Critique de la raison pure. Can we ever be more fully conscious of the relativity of our knowledge, that when we see that what we know of celestial phenomena is admirably precise so long as the solar system is concerned, but is reduced to almost nothing if we look beyond it?
Our world will perish, and its disappearance like its existence, will perhaps be an imperceptible incident. By the continued resistance of the general milieu, says Comte, in the end our world must be re-united to the solar mass from which it came, until, in the immensity of future ages, a fresh dilatation of this mass shall organise a new world in the same manner, destined to repeat more or less completely the former cycle. Moreover, all these immense alternatives of destruction and of renewal have to be accomplished without influencing in any way the more general phenomena due to solar interaction; so that the great revolutions in our world would only be secondary and, so to speak, local events, in relation to transformations of a really universal character.132
This outlook into the “immensity” of space and of duration suffices to show that Comte was not a prisoner in the little solar fatherland in which he seems to seclude himself. It may be that for moral and religious reasons he will not allow himself to go beyond it. But, like Pascal, he well knows that he inhabits “a little out of the way district of nature.”
CHAPTER III.
THE SCIENCES OF THE INORGANIC WORLD
If we do not separate chemistry from physics, their common object is the knowledge of the laws of the inorganic world. In this way they are clearly distinguished on one hand from astronomy which we may consider as an “emanation from mathematical science,” and on the other hand from biology. The distinction between physics and chemistry presents a greater difficulty. Nevertheless this distinction must be maintained, since the physical phenomena are more “general,” and the chemical phenomena more “special,” that is to say, the latter depend upon the former, without this dependence being for the most part reciprocal. Even if some day we succeeded in establishing that chemical phenomena are in reality physical, the distinction would none the less subsist, in this sense, that in a fact termed chemical, there is always something more than in a fact which is simply physical, namely, the characteristic alteration which the molecular composition of bodies undergoes, and which consequently affects the totality of their properties.133
To speak only of physics in the first place, this science presents different characteristics from those of astronomy. The speculative perfection of a science is measured by two correlative although distinct considerations, by the more or less complete co-ordination of the laws, and by the more or less accurate prevision of facts. Now, under one aspect or the other, even supposing that physics should make very important progress, it will always remain very much behind astronomy. Indeed, the celestial science presents an almost perfect unity; physics, on the contrary, is composed of several branches which are almost isolated from one another, and each one taken by itself cannot even reduce all its laws to a more general law. And, as to the second point, while a very small number of direct observations allows of rational and exact prevision of the whole of the celestial phenomena, physics only renders possible predictions which are generally founded upon experience at once immediate and within easy reach. Undoubtedly some parts of physics allow of the use of mathematical analysis (we shall see presently under what conditions). Nevertheless, the part played by experience is infinitely greater in physics than in astronomy. So it is in the former science that we first meet with the inductive method, which is afterwards used and developed in the other positive sciences. Although deduction continues to fulfil an important part, it already ceases to predominate here, because, says Comte, in it the institution of true principles begins to become more troublesome than the development of accurate consequences.134
The inductive method implies these essential processes; 1 observation properly so called, that is to say the direct examination of the phenomenon such as it appears naturally: 2 experimenting, which is usually defined as the examination of the phenomenon more or less modified by artificial circumstances instituted by us in order to study it better; 3 comparison, that is to say the gradual consideration of a succession of analogous cases, in which the phenomenon becomes more and more simple. Of these three processes astronomy only makes use of the first. Physics cannot use the third which is reserved for biology; but it avails itself of the first and institutes the second. This is a fresh confirmation of the law established by Comte: to the complexity and increasing difficulty of the sciences, corresponds an increasing development of the processes of the positive method applicable to them.
Research by way of experiment, which is impossible in Astronomy, appears in Physics. It is therefore here where it originates that we must study it. It is also here that it is most successful, and gives the greatest number of results. Indeed, to experiment successfully we must be able to compare two cases “which present no other difference direct or indirect, than that which relates to the course of the phenomenon under analysis.”135 By experimenting, Comte here clearly designates what John Stuart Mill will call the method of difference, that is to say the most powerful of his methods for the investigation of phenomena.
Now, experimenting, so understood, is extremely difficult when very complicated phenomena are concerned. In physiology, for instance, the experiments must be combined in such a way as to maintain the subjects in the living state, and even, as far as possible, in the normal state. But any modification of one part of the organism immediately affects the other parts. The living being reacts instantly, and adapts itself as best it can to the new conditions in which it has been placed by the experimentalist. We can therefore hardly ever establish in physiology what is so easily obtained in physics: two cases exactly similar in all respects, except in the one which we want to analyse. In chemistry, it is true, experimenting would seem to be even easier than in physics, since in it, as a rule, we merely consider facts resulting from circumstances which are produced by man’s intervention. But this is to mistake the nature of the experimental method. The essence of this process does not consist in man’s institution of the circumstances surrounding the phenomena; it lies in the “freest possible choice of the case best suited to show the law of the phenomenon,” whether this case be, moreover, natural or artificial. Now, this choice is nearly always easier in physics than in chemistry. For the chemical phenomena more complex in themselves, in general can only be brought about by the co-operation of a great number of different influences; for this reason in chemistry, it is more difficult to modify the circumstances under which phenomena are produced, and still more difficult to isolate as completely as in physics the various conditions by which phenomena are determined.
To the use of the experimental method, physics can often join that of mathematical analysis. But in the employment of the latter it must be extremely cautious, and we must only have recourse to this application of mathematics after having “carefully considered the reality of the starting point,” which alone can guarantee the solidity of the deductions. In a word, the spirit proper to physical investigation, must constantly direct the use of this powerful instrument. Now, this condition has not always been fulfilled. Too often the preponderance of mathematical analysis has been the cause of the neglect of experimental studies. Not only has mathematical analysis in this way retarded the progress of physics but it has even tended to vitiate the conception of that science, and to bring it back to a state of obscurity and uncertainty which, says Comte, notwithstanding the apparent severity of the forms differs little, at bottom, from its old metaphysical state.136
For this reason, the application of analysis to physics must not be left to geometers who are chiefly concerned with the instrument. It must belong to the physicists who before all things consider the use to be made of it. Mathematicians have often encumbered physics with a quantity of analytical labour founded upon very doubtful hypothesis; they must give way to physicists trained in experimental studies, and, nevertheless, with sufficient knowledge of mathematics to make use of the analysis whenever it is possible. Within these limits mathematical analysis will render the greatest service to the science of physics. Would optics, acoustics, the theories of heat and of electricity have reached the point where we see them to-day without the powerful help of analysis? Yet even here, physical researches are almost always so complex that, in order to assume a mathematical form, they demand the setting aside of a more or less essential portion of the conditions of the problem. Indeed we are here in presence of the general problem of the translation of the concrete into the abstract. This problem, which is admirably solved in mathematics, and sufficiently in astronomy, is only imperfectly solved in physics. The art of closely combining experience and analysis, says Comte, is still almost unknown. It constitutes the final progress of the method proper to the deeper study of physics.137 We may add, and this is in Comte’s mind, that conversely the progress made by this art would be useful to analysis itself.
II.
Astronomy has reached a perfect state of “positivity.” All trace of the metaphysical spirit has disappeared from it. Can we say as much of physics? It would not seem so, when we see the hypotheses which play so great a part in this science, and of which a few are keenly contested by Comte.
How can we distinguish the valuable hypotheses from the useless ones, those which are useful to physics from those which are merely an encumbrance and should be rejected? This is not a question which can be solved by referring to abstract rules. In order to answer it, we must study the use of hypotheses where it is perfect, and decide according to this example. To my mind, says Comte, the deeper study of the art of hypotheses in astronomy can alone establish the rules which are suitable to direct the use of this precious artifice in physics, and more so still in the remainder of natural philosophy.138 Now of what use is it to astronomers? To anticipate the results of deduction or of induction, “by making a provisional supposition concerning some of the very notions which constitute the final object of the research.” It is a process of which the methods of approximation used by geometers originally suggested the general idea. They “supposed” that the circumference was the limit of the perimeters of inscribed and circumscribed polygons the number of whose sides went on increasing. In the same way, hypotheses provisionally fill up the “lacunÆ” of our knowledge.
An hypothesis should always be open to a positive verification, “whose degree of precision is in harmony with that of the corresponding phenomena.” For it only expresses beforehand what experience and reasoning might have made known immediately, if the circumstances of the problem had been more favourable. If, therefore, an hypothesis claimed to attain that which in its nature is inaccessible to observation and to reasoning, it would immediately become illegitimate and harmful. In a word, it must bear exclusively upon laws, and never upon causes or the modes of production of phenomena.
In the physics of his own time Comte finds the two kinds of hypotheses, but he also finds more bad hypotheses than good ones. He especially protests against the ethers and the fluids to which the phenomena of heat, light, electricity and magnetism were attributed. These hypotheses, according to him, are destined to disappear from science. It is true that the physicists deny that they attribute an objective reality to their ethers and their fluids. They claim to need them absolutely in order to facilitate the conception and the combination of phenomena. However, in spite of themselves, they are drawn into speaking of their ethers as if they really existed. Moreover, do they not see that astronomy gets on very well without similar hypotheses? In order to conceive the phenomena it is enough to observe and analyse them attentively. And, as to combining them, that depends upon the knowledge which has been obtained of their positive relations.
The corpuscular theory is, on the contrary, an example of a good hypothesis in physics, where it plays a part analogous to that of the inertia of bodies in mechanics.139 The innermost structure of bodies is unknown to us. But we have a right to introduce all the hypotheses which can help us in our research, and in particular the hypothesis of atoms, so long as we do not understand it as something representing a reality.
The ethers and the fluids tend to “explain” the physical phenomena by the nature of the agent which produces them. It is here that these hypotheses bear the mark of the metaphysical spirit. To understand the appearance and especially the persistence of these hypotheses, it is not enough to consider them in themselves. We must get back to the history of physics, and compare it with that of the other fundamental sciences. Was it possible for physics to pass suddenly from the period in which phenomena are referred to causes and essences, to the positive period where they are conceived as simply subject to laws? A period of transition was necessary. The scholastic entities, before disappearing, became semi-materialised. They were transformed into fluids. What is heat conceived as existing apart from a hot body, light independent of a luminous body, electricity separated from an electric body? They are the old entities in a new garment, more easily grasped, in spite of their “equivocal corporeity.” They gradually lead to the more and more exclusive consideration of phenomena and of laws, until, in their turn, they disappear.
Astronomy went through the same phases before Physics. In it we have also seen hypotheses which cannot be verified come to facilitate the transition from the theological to the positive state. Such was the conception of Descartes who explained the celestial motions by the system of vortices. Those famous vortices introduced the idea of a mechanism where Kepler himself had only dared to conceive the incomprehensible action of souls and genii. Then Newton came, who preserved the idea of mechanism, while giving up the vortices. In vain did the Cartesians fight against his entirely positive conception. Their arguments in favour of fluids and ethers were as plausible as those of the physicists of our own time. But we have ceased to listen to them. Having become entirely positive, astronomy no longer seeks anything but the laws at work in the phenomena observed. Every accessory hypothesis aiming at anything else has no further interest for us.
The most advanced portions of physics have already reached this point. Take, for instance, the study of gravitation. There was not perhaps a single scientific man of any importance in the XVII. century, even long after Galileo, who did not construct or adopt a system concerning the fall of bodies. At that time any science on this subject seemed impossible without a hypothesis of this kind. Who troubles himself with it to-day? We may be allowed to think that the other parts of physics will follow the same line, and that in turn they will conform to this rule of the positive method: “Every hypothesis must bear exclusively upon the laws of phenomena, and never upon their modes of production.”
III.
In the series of the fundamental sciences Chemistry appears to fill a somewhat secondary and subordinate place. In it the positive method is not enriched by any process of capital importance, but it confines itself to developing the processes already made use of in physics. In spite of appearances, even experimenting is less easy and less fertile in chemistry than in physics. The only new process which we see appearing is the art of nomenclature. Whenever we wish to study this art “at its source” we shall have to refer to chemistry.140
The phenomena which it studies are the most complicated of the inorganic world. If then physics is extremely imperfect, it is not surprising that chemistry should be much more so. In the greater number of its researches “the chemistry of the present day hardly deserves the name of science.”141 But this inferiority of chemistry is not only due to the nature of its object. There are other causes which it would be easier to remedy. The progress of chemistry is retarded: 1, by the wrong direction given to much of its work up to the present time; 2, by the defective education of the majority of the scientific men who give themselves to its study.
Before all things, chemists lack a clear and rational idea of their science, of its relation to the sciences which stand nearest to it and the way in which its problems should be stated. Being intermediate between physics and biology, chemistry has suffered from the vicinity of both. As the more advanced sciences always have a marked tendency to encroach upon those above them, chemistry must in the first place defend itself against the ascendency of physics, as physics itself must fight against that of mathematics. The chemist must undoubtedly have studied physics, in order to make use of the results obtained by this science, and to turn them, if he can, into a method for his own use. The relation of these two sciences is very close, and a knowledge of the laws of calorific and electric phenomena, for instance, is of the highest importance for chemical research. But, for all this, the chemist has his own point of view. He studies, (which the physicist does not do), the laws of the phenomena of composition and decomposition which are the result of the molecular and specific action of diverse natural or artificial substances upon each other. He must therefore make use of physics, but not subordinate himself to it.
On the other hand physiological research is not within the province of chemistry. What has been called “biological chemistry” belongs, according to Comte, to biology alone. For the physiologist to have gone through the school of chemistry is natural and even indispensable. But his point of view is quite different from that of the chemist. As a matter of fact, chemists have shown themselves unqualified for physiological studies. None of their numerous attempts have succeeded in establishing a single point of general doctrine, in biology. They merely furnished materials. Moreover these cannot be used just as they are by the physiologist, who is obliged to take up the researches again “under the preponderating influence of biological considerations.” Comte admires the self-confidence of the chemists who approach physiological questions without having measured or even suspected the special difficulties. It is, however, clear that the most carefully made chemical analyses must be fruitless here so long as they are not directed in the first place by a precise physiological notion of the whole of the phenomenon, and then modified by the knowledge of the limits of the normal variations to which the phenomena may be liable. Now, for proceeding in this manner, the physiologists alone are competent.142
Analogous considerations lead Comte to reject even organic chemistry. Although the chemical phenomena present characteristics which in the inorganic world come nearest to the solidarity which subsists between the elements of living forms, nevertheless chemical phenomena remains irreducible to living phenomena. That which is chemical is not yet organic; and that which is organic is no longer purely chemical. We must do away with this heterogenous and fictitious grouping which is called organic chemistry, to unite the different parts, according to their respective nature, some to chemistry proper, the others to biology.143
How can we define the object of this science, so imperfectly determined at the present time? Comte knows that he is about to depart from the methods generally in use among chemists, but he is not afraid of this. For, he says, in order to understand the real nature of a science, we must always suppose it to be perfect.144 As chemistry, is in an extreme state of imperfection, the “scientific type” which the philosopher conceives respecting it will appear to be very far removed from what exists at present. It matters little so long as this type is perfectly “rational.”
What is essential to science is the possibility of foreseeing phenomena. Given the characteristic properties of the simple or complex substances placed in chemical relations with each other under well defined circumstances, the object of chemistry will therefore be to determine exactly in what their action will consist, and what will be the properties of the new substances produced.145 According to this definition, the fundamental data of chemistry should be ultimately, reducible to the knowledge of the essential properties of the simple elements alone, which would lead to that of the various immediate chemical substances, and consequently to the most complex and distant combinations. Obviously, the study of simple bodies can only be made by means of experiments, which alone reveal their properties. But, once this basis is laid down, “all the other chemical phenomena, notwithstanding their immense variety, should be capable of rational solutions, according to a small number of invariable laws, established by the science of chemistry for the various classes of combinations.”
Thus, Comte sees clearly that the complexity of the chemical phenomena prevents us from expressing their relations in a form which allows of the use of mathematical analysis. But none the less, in this science as in the preceding ones, he persists in making the experimental method a mere starting-point. The experimental method furnishes the data which it alone can supply. But these data are afterwards elaborated without its intervention. The scientific ideal in chemistry, as in physics and in astronomy, is to substitute as much as possible rational prevision to experimental verification. Science always seeks to deduce the greatest number of consequences from the smallest number of data, and the smallest number of data in this case are the properties of simple bodies. Deduction will establish a priori what the properties of a given combination of two simple bodies, or of two complex bodies will be.
In the name of this scientific ideal, Comte reproaches the chemists with the superabundance of their analytical work. In default of a rational conception of chemistry they do not make their work bear upon the necessary points. What is the use of studying such and such a body, placed in such and such conditions, in an arbitrary way and according to the fancy of investigation? The progress of chemistry should consist far less in the acquisition of new materials than in the systematisation of those which we already possess. Chemistry is to-day as rich in details as it is imperfectly constituted as a science.146 Its present state in no way gives an idea of what its normal state will be.
Not content with showing to chemists the “scientific type” towards which their science should tend, Comte suggests a contrivance in method which will bring them nearer to it. It is in no way like the hypothesis of affinities, for this appears to him to be even more “ontological” than the hypothesis of imaginary fluids or ethers. As always happens when we are concerned with metaphysical conceptions, the explanations which we draw from affinities consist in the reproduction in abstract terms of the very statement of the phenomenon.147 To this hypothesis, which is not a scientific one since it bears up the mode of production of facts, Comte substitutes what he calls the “dualist hypothesis.” We ignore, he says, and it is not for us to seek the real manner in which the elements of which bodies are composed come to be grouped together. But, consequently, it is lawful for us, in the very circumscribed sphere of our positive research, to conceive the immediate composition of any substance whatever as merely binary, each of the two bodies so separated being able, according as the case may be, to lend itself to a similar analysis, equally binary, and so on, as the occasion arises. We do not affirm that dualism is a real law of nature. It will be a fundamental contrivance in chemistry, like the hypothesis of inertia in mechanics, and that of atoms in physics. It will serve to “simplify our elementary conceptions” in chemistry, and in having recourse to it we do not exceed “the special kind of liberty” of which our intellect may avail itself, in the institution of science.148
The use of this hypothesis would allow us to endow chemistry with a “fine” character of unity and rationality which it lacks to-day. It is true that Comte himself confessed that this hypothesis, proposed by him in 1838, had yet “produced nothing” in 1851. But he explains this sterility to himself by the metaphysical spirit, from which chemists are not sufficiently freed.
IV.
We can now take in at a single glance the relations of the sciences of the inorganic world (including astronomy), with the totality of positive philosophy.149
In several ways these sciences have contributed to the progress of the positive spirit. By their constitution, they allowed and prepared the formation of the more complex sciences of Biology and of Sociology. Moreover, their development struck a mortal blow at theological and metaphysical philosophy. Through them minds became familiarised with the idea of natural law. This idea was not so clearly brought to light by mathematics on account of their almost purely abstract character, and of the imperceptible part played in them by observation. It appears, on the contrary, as the mainspring of astronomy, of physics, and of chemistry. The whole effort of these sciences tends to discover invariable relations between phenomena given in experience.
Theological philosophy is the “explanation” of nature which the human mind first makes for itself. In order that it may give up this “explanation” some contrary evidence must oblige it to do so. It may see for instance, that phenomena can be predicted with a perfect exactness which is always confirmed by experience, or that man, under certain conditions, can modify them with certainty. Astronomy gives us an example of the former case. It studies phenomena which, it is true, are removed from our sphere of action. But, in return, it predicts them with a certainty of which the effect has been practically infallible in the long run. It is astronomy which has done most to discredit the religious and philosophical doctrine of final causes.150 Not only has it proved that the universe is not disposed with reference to man, but it has shown the imperfections of our solar system. It has helped more than any other science to check the mental habit of seeking the mode of production of phenomena.
Physics is far from allowing of a rational prevision which is comparable to that practised by astronomy. But, as a compensation, it shows how the knowledge of laws gives the power to cause phenomena to vary with certainty. This second way leads us no less surely than the first to the positive conception of nature. For example, Franklin destroyed the religious theory of thunder, even in the least cultivated intellects. The discovery of the means of directing lightning therefore had the same effect, in another way, as the exact prevision of the return of comets.151
On the other hand the sciences of the inorganic world furnish the general positive method with some of its most powerful processes. Astronomy introduces observation and hypothesis into this method, Physics adds experimenting to it, and Chemistry the art of nomenclatures. The inductive method, which virtually consists in simple scientific observation, becomes, however, enriched and is developed, according as the phenomena in question become more complicated.
But, in return, positive philosophy exercises a considerable influence over these sciences. It claims nothing less than to direct and “regenerate” them. Viewing them from above and as a whole, philosophy can bring a remedy to the difficulties which arise from their specialism. It sets an exact limit to each of the sciences. It delivers physics from the “algebraical yoke,” and protects the independence of chemists against the encroachments of the physicists. It places the entirety of the positive method at the service of each particular science. For instance, it directs the use of hypothesis in physics by the theory drawn from the use which is made of it in astronomy; for classifications, it extends to chemistry the use of the comparative method which properly belongs to biology. When, later, the integral and final constitution of the philosophy of our age shall have organised the relations between all the sciences, it will be almost impossible, save from the historical point of view, to understand how the study of nature was ever conceived and directed otherwise.152
Positive philosophy organises labour within each science, and puts an end to “anarchy.” It distinguishes between “idle” researches, and those which should be pursued. It avoids waste of efforts and prevents digressions. We have seen within what limits Comte wishes to enclose astronomy in the name of philosophy. He does not perceive the means by which he can unite the various branches of physics; but he claims to replace the fragmentary and scattered chemistry of his time by a single systematic science, which will forsake the researches of detail which are without interest for humanity. “Almost the whole of those innumerable compounds will not finally be worthy of any scientific attention. Some well-chosen series may even be able to satisfy the logical requirements of chemistry for the discovery of the abstract laws which belong to each order of composition.”153
Finally positive philosophy causes the disappearance of the last remains of the theological and metaphysical spirit from the sciences of inorganic nature. This philosophy has already shown that mathematics is not a more absolute science than the others, and that it originates in experience. In physics and in chemistry it banishes the hypotheses which, more or less avowedly, tend to make us conceive the essence or the mode of production of phenomena. It is thus that it demands a science of physics freed from ethers and fluids, and a wholly rational chemistry which shall give up affinities.
Comte is not therefore possessed of a superstitious respect for the sciences in the state in which they appear before him. On the contrary, he intends that they should be subject to deep modifications, and that they should strive towards an ideal form which is laid down for them by philosophy. He calls this form “positive.” In reality it is Cartesian.
CHAPTER IV
BIOLOGY
The passage from the inorganic world to the world of Life constitutes a critical step in natural philosophy. Astronomy, Physics, and Chemistry represented successive steps in the same series. If each order of phenomena presented in itself something which was irreducible to previous orders, nevertheless all these phenomena, in a certain sense, remained homogeneous. Without rashness, Descartes could conceive that physics, like astronomy, would one day assume the mathematical form. And to-day more than one scientific man considers the distinction between physics and chemistry as provisional.
But as soon as life appears, we enter a new world. At this degree the “enrichment of the real” is suddenly so considerable that we find it difficult to admit the homogeneity of these phenomena with the preceding ones. Comte here reaps the benefit of his prudence. His philosophy has guarded against reducing all science to a single type, and it is content with the unity of method and the homogeneity of doctrine. It only demands that each science should limit itself to the search after the laws of phenomena. As to the way in which this research is to be carried out, it is evidently subordinated to the nature of the phenomena in question. Now, biological phenomena present a number of characteristics which belong to them alone, and the first duty of the positive science which studies them is to respect their originality.
Comte, therefore, here breaks with Descartes who conceived biology as a prolongation of physics. He takes an entirely different view of this science, which, in a sense, is opposed to the whole of the sciences of the inorganic world. From this there arises a double effort. On the one hand, Comte wishes to maintain the continuity of the encyclopÆdic series of the sciences: he thus shows Biology as immediately following chemistry, and maintaining the closest relations with astronomy and physics. On the other hand he clearly brings out the irreducible character of the vital phenomena, and the modifications which the positive method must undergo when applied to them. Despite the extreme difference between the points of view and the doctrines, he often makes us think of those deep and difficult passages in the Critique du Jugement where Kant has shown that without the hypothesis of an inner finality, (although this hypothesis is in itself obscure), the phenomena which take place in living beings remain unintelligible.
With biology, says Comte, necessarily appear the ideas of consensus, of hierarchy, of “milieu”, of the conditions of existence, of the relation between the static and the dynamic states, between the organ and the function.154 In a word, a biological phenomenon, considered alone is devoid of meaning. Strictly speaking, it does not even exist. It can only be understood by its relations with the other phenomena which take place in the living being, phenomena which react upon it. At the same time it reacts upon them. Here, in opposition to what takes place in the inorganic world, the parts are only intelligible through the idea of the whole. Undoubtedly a certain solidarity of phenomena exists in the inorganic world, which allows us to consider united wholes in it. But the solidarity of biological phenomena is far closer, for, without it we could not conceive them, while, as regards the phenomena of the inorganic world, there is nothing impossible in this abstraction.
Henceforth, the positive method must adapt itself to the characteristics which belong to biological phenomena. It does not always demand, as it has been wrongly stated, that we should go from the simple to the complex, but only that we should proceed from the known to the unknown. It is true that in the sciences of the inorganic world we proceed from the least complex to the most complex cases; we begin by the study of phenomena which are as isolated as possible from one another. But, on the contrary, living beings are all the better known to us in proportion as they are more complex. The idea of the animal is in some respects clearer to us than the idea of the vegetable. The idea of the superior animals is clearer to us than that of the inferior ones. Finally man for us is the principal biological unity, and it is from this unity that speculation starts in this science.
Thus, in dealing with Biology the positive method undergoes a veritable inversion. In the preceding sciences, the last degree of composition is forbidden us: we never succeed in uniting the whole of the inorganic world into a single synthesis. In biology, on the contrary, sums of phenomena are given; but it is the last degree of simplicity which escapes us. We have to start from those sums of phenomena, and biology must in this way assume a synthetic character. In it the analysis of phenomena will be as minute as possible; but the analytical operations will always be more or less directly subordinated to the leading idea of the vital consensus.155
II.
Like the other fundamental sciences Biology must be abstract, that is to say it must not bear upon individual beings, but upon phenomena. It is thus distinct from zoology and botany which are concrete sciences. In its widest generality it is defined through the constant correspondence between the anatomical and the physiological point of view. Its object is to constantly unite them to one another. In reality these two points of view are the two aspects of a single problem. It is owing to historical reasons that, during a certain time, these two sciences appeared to develop independently of one another. Physiology remained attached to the metaphysical methods, that is to say, to unverifiable hypotheses and to principles which went beyond experience, while anatomists already made use of the positive method. But to-day, the two sciences being equally positive, “their opposition is reduced to that which subsists between the static and the dynamic points of view.”156
Another element which should enter into the more general definition of biology, although it has sometimes been neglected, is the consideration of the milieu. The relation between the organism and its milieu is no less essential to life than the relation of the organ to the function. Life supposes not only that the being should be organised in a certain way, but also that a certain number of external circumstances should sustain this organisation, and should be compatible with its activity. Living beings are thus dependent upon their milieu, and this dependence grows as we rise in the organic series. The system of the conditions of existence becomes all the more complex as the functions develop and become more varied. Inferior organisms are subject to less numerous external conditions; but, says Comte, a little variation in one of these conditions suffices to make them perish. The superior organisms stand a variation of this kind better. But, in return, the number of conditions upon which they depend is far greater. The study of milieux in their relations to organisms, a study which is hardly outlined, undoubtedly has many discoveries in store for the future.157 Here is an order of problems of which Lamarck probably suggested the idea to Comte, and upon which Darwin’s genius will work.
Bichat then was wrong in saying in his celebrated definition of life that it is “the sum of the forces which resist death.” The radical antagonism between inorganic and living nature is an incomplete and consequently a false idea. Indeed if, as Bichat supposed, everything which surrounds living bodies tended to destroy them, their existence would become unintelligible.158 Where could they find strength to resist such formidable pressure, even for a short time? On the contrary, the fundamental condition for life is a certain “harmony” between the organism and the milieu in which it is placed. The proof of this is furnished at every turn by experience.
This being established, what will be the most general problem of the science of life? From the anatomical point of view, says Comte, all possible organisms, all parts whatever of each organism, and all the various states of each necessarily present a common basis of structure and of composition, from which the tissues, organs and apparatus have emerged by means of a progressive differentiation. In the same way, from the physiological point of view, all living beings, from the vegetable kingdom up to man, considered in all their actions and all the periods of their existence, necessarily possess a common basis of vital activity, whence the innumerable phenomena of nutrition, secretion, etc., proceed, by means of progressive differentiation. Now, from both these points of view, that which is similar in these cases, is more important than that which distinguishes them, since the more general phenomena govern those which are less so. We must therefore disengage the elementary physiological phenomenon and the anatomical structure which corresponds to it, we must determine their relation, and, with the help and confirmation of experience, we must deduce the increasingly more complex, physiological and anatomical, phenomena from it.159
This conception which, despite Comte’s reservation, still appears to be entirely saturated with the Cartesian spirit, leads him to the “most mathematical statement possible” of the biological problem. “Given the organ, or the organic modification, to find the function or the act, and vice versa.”160 There is nothing more in conformity with the general definition of science, which consists in substituting the knowledge of laws to that of facts, and rational prevision to empirical observation. Here, it is true, we have an “ideal scientific type,” from which biology, which has scarcely reached the positive state, is very far removed. But there is no science which does not fall short of its definition more or less. The use of this definition is already a help for a science, and provides a means for measuring its progress.
III.
In part, or even entirely, biology is deprived of certain methodical processes which are utilised by the sciences which precede it. It cannot avail itself of calculation. Undoubtedly each of the elements which go to make up a physiological phenomenon varies according to a definite law. But the sum of these elements forms such a complex whole, that we shall never be able to express their relations in the terms of an equation. Further, the numbers which are relative to the phenomena of living bodies present continual and irregular variations, which do not allow us to establish the data of a mathematical calculation.161 Each living being has its individuality, its personal formula, its characteristic reactions, which prevent us from treating it as identical with the other beings of the same species. Each physiological or pathological “case” is distinct from any other case. That is why Comte distrusts statistics. In his judgment they are misleading in physiology, and fatal in medicine. In the same way, Claude Bernard will protest vigorously against averages.
Is the inductive method at least a convenient one to make use of in biology? Simple observation cannot lead us far in the study of such complex phenomena, of which many are not directly accessible to our senses or to our instruments. Experimenting is very difficult in biology, for nothing is easier than to disturb, to suspend, or even to bring about the entire cessation of the phenomena of life. But it is almost impossible to introduce an exactly determined perturbation, whether of kind, or, a fortiori, of degree. Indeed a modification of a single condition of the phenomenon almost at once affects the greater number of the other phenomena, by reason of their consensus. In principle, experimenting is not forbidden in biology. On the contrary it is of remarkable efficacy, but it is often impracticable.
Nevertheless, as we know, it is not man’s intervention in phenomena which constitutes experimenting properly so called. It consists, before all things, in the rational selection of cases, (natural or artificial, it matters little), which are most appropriate for bringing out the law of variation of the phenomenon under observation. Nature gives us such, for illnesses resemble experiments which we can follow through their entire course and to their termination. They are often difficult to interpret, on account of their extreme complexity, but less so, however, than the majority of the experiments which we bring about ourselves. For are they not more or less violent diseases, suddenly produced by our intervention, without our being able to foresee all their indirect and future consequences? It is pathological anatomy which led Bichat to his fine discoveries in histology and in physiology. And to pathology we must join teratology which is, as it were, its prolongation. Here again, nature supplies experiments which we should not know how to institute.162
Whatever may be the help which biology derives from these natural ways of experimenting, its progress could only be a very slow one, if it did not possess besides a powerful method for proceeding which is peculiar to it: comparison. It is true that every inductive operation implies comparison. We compare what we observe with other real and possible cases. Again we compare when we are experimenting. But, in the comparative method, properly so called, we do not limit ourselves to bringing two cases together. Comparison bears upon a long sequence of analogous cases, in which the subject is modified by a continual succession of almost insensible gradations.163
How would the general problems of biology receive a solution without this method? If we consider an organism by itself, the complication of functions and organs is inextricable in it. But, if we compare this organism with those which come nearest to it, and then with others which are near to them and so on, disengaging what they have in common, a simplification is produced. The accessory characteristics disappear by degrees, as we descend in the biological series, and, if we have set ourselves to study a certain function, we can finally determine its relation to its organ.
Although it belongs to biology, this method has its analogy in other sciences, and especially in mathematics. It appears to me, says Comte, to present a character similar to that of mathematical analysis, which brings forward, in each sequence of analogous cases “the fundamental portion which is common to all, which portion, before this abstract generalisation, was concealed beneath the secondary specialities of each isolated case.” The comparative method, in a word, is a method for analysing biological continuity. Whether it be a question of an anatomical disposition or of a physiological phenomenon “the methodical comparison of the regular sequence of the growing differences which relate to them will always present the surest and most efficacious means of throwing light upon even the ultimate elements of the proposed question.” We see that Comte had here his conception of the infinitesimal calculus in his mind. Better still, where terms are lacking in the organic series he does not hesitate to suppose them to re-establish continuity. He introduces intermediary “fictitious organisms” hypotheses which some day perhaps palÆontology will turn into realities.
By means of this method, not only we shall know a far greater number of cases, but, what is of more importance, we shall know each one among them better, “as an inevitable consequence of their being drawn nearer together.” We assume, it is true, that all these various cases present a fundamental similarity accompanied by gradual modifications, which always follow a regular course. But this hypothesis as we have seen, is implied in the very definition of general biology.
The comparative method will then apply successively to the different parts of an organism, to the different ages of the same organism, and to the different organisms in the animal and vegetable series. It will even apply to embryonic life, Comte clearly formulates von Baer’s law, while making indispensable reservations. The primitive state of the highest organism, he says, must represent, from the anatomical and physiological point of view, the essential characteristics of the complete state which belongs to the more inferior organism, and so on successively “without our being able to find again the exact analogy of each of the principal terms of the inferior organic series in the sole analysis of the various phases of development of each superior organism.” This comparison, so to speak, allows us to realise in the same individual the growing complication of organs and of functions which characterises the whole biological hierarchy. Thus it is particularly “luminous.”164 Von Baer’s book had appeared in German in 1827. Had Comte known it, it is most probable that, according to his habit, he would have quoted it.
IV.
In order to consider organisms in the regular sequence which allows of comparison, we must first have established the order in which they should be arranged. But, conversely, to establish this order, a knowledge of anatomy and physiology is indispensable. So between these two sciences on the one hand and “biotaxy” on the other there is a strict solidarity. The problem of classification is thus an essential part of general biology. In the natural classification sought after by science, the position assigned to each organism would suffice to define at once the whole of its anatomical and physiological nature, in relation to the organisms which precede and to those which follow.165 Any natural classification cannot, however, be anything but imperfect. Accustomed as we are to artificial classifications, which admit of absolute and immediate perfection, we are surprised that the same should not be the case in natural classification. But, if the latter is a real science, we must own that, here as elsewhere, we can only reach more or less distant approximations. The co-ordination of living species is a problem like the static or dynamic analysis of a determined organism. Like this analysis, it only allows of solutions which are approached rather than realised.166
How, in the first place, must we understand species? Between Cuvier and Lamarck, Comte sides with Cuvier, with this reservation, however, that “our ideas upon this question of capital importance are not yet properly fixed.” Two reasons especially incline him to admit the fixity of of species. Lamarck’s theory is not sufficiently proved: we nowhere see that the milieu exercises the almost boundless influence upon organisms which is attributed to it by Lamarck. Undoubtedly, within certain limits, the exercise induced by external circumstances tends to modify the primitive organisation. But this action of the milieu and this aptitude of the organism are certainly very limited. On the other hand, if we have a choice between the two hypotheses, the interest of science would prompt us to use this liberty in favour of Cuvier. The fixity of species guarantees that the series of organisms will always be composed of terms which are clearly distinct, separated by insuperable intervals. This “increases the degree of rational perfection of which the final establishment of this hierarchy is capable.”167 It is then under the influence of a purely formal motive that Comte’s preference is here decided. For he felt the strength and the import of Lamarck’s labours. Of the two celebrated antagonists, he said, Lamarck was unquestionably the one “who manifested the clearest and deepest sense of the true organic hierarchy.”168
Comte has even dealt with certain objections which do not go against Lamarck. Thus, we might think at first that, in his hypothesis, there is no real zoological series, since animal organisms would be essentially identical, their differences being henceforth attributed to the diverse and unequally prolonged influence of the external conditions. But, on looking into it more closely, we see, on the contrary, that this hypothesis only presents the series in a new aspect which would even render its existence still more evident. For the whole of the zoological series would then become, in fact as well as ideally, altogether analogous to the whole of the individual development, confined at least to its ascending period. It would then be conceived as continuous. “The progressive advance of the animal organism, which for us is only a convenient abstraction, would be converted into a natural law.”169
For the logical perfection of science, Comte prefers to regard species as fixed in the absence of contrary proofs. None the less Lamarck has stated a problem of the highest interest. Comte points out its importance. “The rational theory of the necessary action of the various milieux on the different organisms has still almost entirely to be formulated. Such an order of research, although greatly neglected, constitutes one of the finest subjects which the present condition of biology can present.” By this means, he adds, we might obtain a theory for the perfecting of living species even including mankind.170
V.
Comte’s anatomical and physiological philosophy is naturally allied to the science of his time. It is especially connected with the labours of Bichat and of de Blainville. Here again he endeavours to state the problems in the most general form possible. Anatomy should begin by the study of the tissues, to ascend afterwards to the association of several tissues, that is to say, to the organs, and to the associations of several organs, that is to say, to systems. But analysis must not be concerned with the tissue itself. To attempt the passage from this notion to that of the molecule, is to allow the organic to enter into the inorganic philosophy. In biology, the tissue corresponds to what the molecule is in physics. Such, at least, is the doctrine of the Cours de philosophie positive. Later on, instructed by Schwann’s works, Comte admits in the Politique positive that the anatomical element is the cell.
Be it tissue or cell, there must be a fundamental anatomical element. The simultaneous existence of several elements independent of one another would greatly mar “the admirable unity of the organic world,” and consequently the perfection of biological science. Life is always essentially the same. To this dynamic consideration, there must correspond, in the static order, that of a common basis invariable in its primordial organisation, successively producing, by deeper and deeper modifications, the various special anatomical elements.
Similarly, physiology will not be entirely organised until it studies functions (at least the organic functions), throughout the whole chain of living beings, from the vegetable kingdom up to man. This conception of a general physiology leads Comte to dwell, as Claude Bernard will later on, upon the phenomena of life which are common to plants and to animals. Some are better studied in plants and others in animals. But, whether it be animal or vegetable every organism always presents two fundamental functions: 1. the absorption of nutritious materials borrowed from the milieu (the assimilation of these materials and finally nutrition); 2. the rejection of unassimilated materials. However, plants are the only organised beings which live directly upon the inorganic milieu.171 Comte was ignorant of the physiology of fungi.
Comte unreservedly adopts the distinction established by Bichat between the functions of organic life and those of animal life. In the first place he concludes from this, in virtue of the correlation of the dynamic to the static point of view, that distinct tissues correspond to these distinct functions. Then, he goes more deeply into the difference between the two kinds of functions. Strictly speaking, the phenomena of organic life only constitute a special order of composition and of decomposition. They come very near to chemistry, and may serve as a transition between the inorganic world and the world of life.172 On the contrary, the phenomena of animal life (irritability, sensibility), offer no analogy with the phenomena of the inorganic world. We might almost believe, according to Comte, that the separation is established not between the chemical and biological phenomena, but between organic and animal life, the phenomena of the former reducing themselves to physico-chemical phenomena, and those of the latter presenting entirely different characteristics. Such is not, however, Comte’s thought. Undoubtedly, considered one by one, the phenomena of organic life (absorption, circulation, exhalation, etc.) are indeed physico-chemical phenomena. But what renders their biological character irreducible is that it is impossible to consider them separately: in order to understand them we must first look at them from the point of view of the whole, and appeal to the organic consensus, in a word, to what Claude Bernard, will call l’idÉe directrice.
In the study of organic functions we shall begin by the lower extremity in the series of living beings, that is to say by the most rudimentary forms of the vegetable kingdom, for it is here that we shall grasp the phenomena in their simplest form. Then we shall follow their growing complexity. For the animal functions, on the contrary, it is expedient to begin by man, “the only being in which such an order of phenomena is ever immediately intelligible.” From this point of view man is pre-eminently the biological unity. As soon as it is a question of the characteristics of animality, we must begin with man and see how they descend by degrees, rather than start from the sponge, and look for their mode of development. Man’s animal life helps us to understand that of the sponge; but the reverse is not true.173 Moreover, the phenomena of organic life, being the most general, are also the most fundamental. The functions of animal life are first useful for the needs of organic life, by perfecting it. It is in man alone that the vegetative life is subordinate to the life of relation: and even for that he must have reached a high degree of civilisation.174
VI.
It is not surprising that biology, even more than physics and chemistry, preserves the metaphysical spirit. Such, for instance, is the hypothesis of spontaneous generation. Positive philosophy recognizes that each living being always emanates from another similar being. This is not established a priori, but is the result of an “immense induction.”175 Omne vivum ex vivo. Efforts to explain how the generating tissue should itself be formed by kinds of organic monads, (an allusion to certain theories arising out of Schelling’s philosophy) can only fail. We should never know how to connect the organic with the inorganic world except through the fundamental laws belonging to the general phenomena which are common to them both. Positive speculations in anatomy and in physiology form a limited system, within which we must establish the most perfect unity, but which must ever remain separated from the whole of inorganic theories.176 We see clearly, it is true, that there is no matter which is of itself living. Life is not peculiar to certain substances which are organised in a certain manner. It never belongs to them for more than a time: every organism of which the molecules are not renewed is dissolved. But “we can no more explain this instability than this speciality.”177
In the same way we see that in living bodies the nutritive functions are the basis of the others; but there is no contradiction in “dreaming” of thought and sociability in beings whose substance would remain unalterable. From this point of view spiritualism is not less admissible than materialism, in so much as death does not seem to be a necessary consequence of life. This again is an idea which is common to Descartes and to Comte. They both conceive an organism in which the play of functions should not cease of itself. The theory of death, says Comte, although it is founded upon that of life, is entirely distinct from it.178
If biology still often hesitates in the statement of its problems and in the choice of its hypotheses, it is in a great measure due to the two opposite tendencies between which it oscillated in the last century. On the one hand, Boerhaave, and the school of physiology which is more or less directly connected with Descartes, sought a mechanical explanation of biological phenomena, and tended to reduce biology to physics and chemistry. On the other hand, Stahl in Germany, and the vitalist school of Montpellier in France, appealed to metaphysical principles and to unverifiable hypotheses. Being thus swayed from one extremity to another, biology only escaped the “oppression” of the inorganic sciences to involve itself in conceptions which were scarcely scientific.179 It is only at the end of the XVIII. Century, with Haller, Gall and Bichat, that it finds its equilibrium, takes possession of its method, and at last enters into its positive phase.
By its lower extremity it is contiguous to inorganic science (the physico-chemical phenomena of vegetative life). By its higher extremity, (intellectual functions), it reaches to the final science, or sociology. But the adherence is far from being as close in one case as in the other. At the moment when we pass from the inorganic world to the world of living beings, according to positive philosophy, there is a sudden “enrichment of the real.” The transition is very marked. The domain of biology is not so sharply separated from that of sociology. For the higher biological functions, the intellectual functions, cannot be analysed from the point of view of the individual, at least in man, but only from the point of view of the species. We must then, while preserving the distinction between the two sciences, admit a kind of inter-relation between them. Undoubtedly sociology could not be founded so long as biology had not made decisive progress. But, conversely, sociology once founded alone completes the positive study of the highest biological functions.
Certainly, biology has not been less transformed than chemistry during the last sixty years, and the state in which we see it to-day differs singularly from that in which Comte knew it. It has been developed and differentiated far beyond what he could foresee. None the less he conceived some of its principles with remarkable power. He had a precise idea of that which could constitute a general biology that is, a single physiology and anatomy for the whole of living beings. He knew the fecundity of the comparative method, and he pointed out its analogy with the method of analysis in mathematics. Finally, although he refused to adopt the transformist hypothesis, he had understood the importance of Lamarck’s work.
CHAPTER V
PSYCHOLOGY
Psychology has no place in the classification of the fundamental sciences. In it Sociology immediately succeeds Biology. Use has been made of this fact in order to reproach Comte with having neglected an order of most important phenomena. A grave objection has been raised against his doctrine in general. What are we to think of a philosophy which, deliberately, omits a part, and, according to many philosophers, the chief part of reality, the world of consciousness, the spiritual nature of man?
Presented in this way, the objection rests upon many confused notions about words and ideas. What do we understand by psychology? If the word means: “the science of the soul reached through the introspective method,” we must own that Comte does not admit the possibility of such a science. But the same objection will also hold good against the majority of the psychologists of our time. For they do not admit this possibility any more than Comte, and they have endeavoured to constitute the science of psychical facts by a different method than that of introspection, pure and simple. Is psychology defined as “the science which investigates the laws of feeling, of the intellect and of moral phenomena in man and in animals?” Then it is inaccurate to say that there is no psychology for Comte. On the contrary, he thinks that positive psychology has just been founded by contemporary science of whose methods he approves. If he did not use the word “psychology,” he did so in order to avoid confusion. At that moment the word was, so to speak, the property of the eclectic school. By the “psychological” method, everyone then understood that of Jouffroy. “Psychology” was the science founded by Cousin on the analysis of the ego. Comte who opposes these philosophers, did not wish his theory of psychical phenomena, which differs from theirs, to be called by the same name. It is this very precaution which has come to be no longer understood, now that “psychology” does not designate the eclectic doctrine alone, but any theory whatsoever concerning mental facts.
I.
Comte finds the field occupied by three psychological schools, and he combats all three, for reasons of method and also of doctrine. He looks to them to refute each other mutually, and he will only attack what is common to them all.180
The representatives of these three schools are the Ideologists, with Condillac, from whom they proceed, then the Eclectics, and finally the philosophers of the Scottish school. Comte sometimes calls the eclectics the German school, in opposition to the ideologists, who are the French school, and to the Scottish school, the first of the three in point of time. But he always speaks sympathetically of the Scottish school, remembering that, in part, he owes to it his philosophical education. He also esteems the sincerity and logical vigour of the ideologist Destutt de Tracy. But, after all, we have here metaphysicians, as are also the eclectics upon whom he passes a more severe judgment. By “metaphysicians,” he understands all those who study phenomena, (in this case psychical phenomena), by means of a method which is no longer theological, but which has not yet become positive. In this sense, Locke is a metaphysician, as well as Condillac and his other successors in the XVIII. century, Hume alone excepted.
Comte showers derision upon the method of internal observation which is practised by the “psychologists.” The sharpness of his language is at least partially explained by the indignation with which Cousin’s “charlatanisme” inspired him. This “famous sophist,” in whom he recognises some of the gifts of an orator, and in particular that of a mimic, according to him, exercises most unfavourable influence over the minds of men.181 He turns them aside from the positive path, which they are about to enter, to bring them back to metaphysical dialectics, or to hollow and sonorous rhetoric. And, to crown all, this “psychology” claims to follow a scientific method! the very method which has succeeded so well in the natural sciences! It conceives the idea of practising internal observation, as physics makes use of external observation. But what is this internal observation? How can the function of the same organ be to think, and at the same time to observe that it thinks? We conceive that man should be able to observe himself if it is a question of the passions which animate him. No anatomical reason is opposed to this since the organs which are the seat of the passions, are distinct from those which are used for the observing functions. But as to observing the intellectual phenomena in the same way, it is manifestly impossible. In this case, the organ which is observed being one with the observing organ, how could the observation take place?
This objection does not only hold against the eclectics, but also against the Scottish school and the ideologists. We already find it set forth in a letter from Comte to Valat on the 24th, of September, 1819, when he was perhaps not yet acquainted with Cousin. “With what should we observe the mind itself, its operations, its activity? We cannot divide our mind, that is to say, our brain, into two parts, of which one acts while the other looks on, to see how it goes to work. The so-called observations made on the human mind, considered in itself and a priori, are pure illusions. All that we call logic, metaphysics, ideology, is an idle fancy and a dream, when it is not an absurdity.”182
This text, to which we could add many similar ones, allows us to rectify an erroneous, although a frequent interpretation of Comte’s thought. He does not deny that we are informed by consciousness of the existence of psychical phenomena. On the contrary, he expressly recognises the fact. What he regards as impossible is to study the activity of thought by means of reflection, that is to discover the “intellectual laws” by a method of internal observation. In a word, it is such works as those of Condillac, of the ideologists, of Reid, etc., which he condemns in their principle. In these works the subject matter is the theory of knowledge, and not that which is called to-day psychology proper.
If, instead of seeking specially for the intellectual laws, we wish to study psychical phenomena in general, internal observation will become possible in a certain number of cases. But it will not lead to the end which we wish to reach. It excludes the use of the comparative method, so fertile and so indispensable in the whole domain of biology. It only studies man, and even adult and healthy man. What will it tell us of the child, of the mentally deranged, of the animal?183 Will it, like Descartes, go so far as to deny the existence of a psychical life in animals? Still this life cannot be studied by internal observation. We must then have recourse to another method.
Strictly speaking, there are only two methods which are suitable for the science of those phenomena. Either we determine with all possible precision the various organic conditions on which they depend: this is the object of what Comte calls phrenological psychology. Or else we observe directly the products of the intellectual and moral activity, and this study then belongs to sociology. But, if by this supposed psychological, method we set aside the consideration of the agent, that is to say of the organ, and that of the action, that is to say of the productions of the human faculties, what can remain “unless an unintelligible logomachy,” or verbal entities which are substituted to real phenomena? Here then is the study of the most difficult and most complex functions suspended, as it were, in the air, without any point at which it touches the simpler and more perfect sciences, “over which, on the contrary, it is claimed that it should reign majestically.”
Nothing is more opposed to the general order of nature, in which we always see the more complex and higher phenomena subordinated, so far as the conditions of their existence are concerned, to the more simple and commoner ones. As the biological depend upon the inorganic phenomena, just as, within biology, the phenomena of animal life are subordinated to those of organic life, so the intellectual and moral phenomena depend upon the other biological functions. Beyond their own particular laws, the laws of all the subjacent orders of phenomena also govern them. Can we study them as if all these laws did not exist? Let the metaphysician be free to do so. The scientific man who follows the positive method will proceed on other lines.
A defective method could lead but to false results. Notwithstanding the differences in their doctrines, ideologists and psychologists have agreed to place the intellectual functions in the front rank, and to thrust the affective functions further back. The mind has become the almost exclusive subject of their speculations. Look at the titles of their great works since Locke’s “Essay on the Human Understanding—Principles of Human Knowledge—On the origin of our Ideas—On Sensations—Ideology, etc.” The various affective faculties have been left comparatively in the shade. Now, it is the contrary which should have been done. Experience shows that the affections, the passions, the inclinations, play by far the most important part in the life of animals and even of man. Far from being the result of intelligence their “spontaneous and independent” impulse is indispensable for the first awakening, and afterwards for the development, of the various intellectual faculties. “Against all evidence man has been represented as essentially reasoning, as being continually performing unaware a multitude of imperceptible calculations with scarcely any spontaneity, even from tenderest childhood.”184
Had the study of the psychical functions been made upon animals at the same time as upon man, this error would not have lasted long. But philosophers were maintained in it, on the contrary, by metaphysical and even theological preoccupations. The science of mental functions had to establish a difference, not only of degree but of kind between man and animals. It was further required, by reason of another necessity closely allied to the former, that the soul should be considered as being immortal. And it was consequently necessary that the “ego” should present metaphysical characteristics of unity, of simplicity and of identity. Now, it is by thought that man is most distinguished from animals. It is therefore from thought that the characteristics attributed to the soul or to the “ego” have been borrowed.
But in fact the “ego” is not the absolute unity which the eclectic psychologists say that it is. It represents the feeling which the superior living being has, at every moment of the “sympathies” and the “synergies” which take place within the organism. It is the conscious expression of what the French call to-day “cÉnesthÉsie.” Far from being directly perceived as Cousin asserts, it is the indirect product of a quantity of sensations and sentiments, of which the majority are not perceived in the normal state.185 It is especially by pathological facts, (diseases of the personality, double consciousness, lunacy, etc.), that the attention of the scientific man is drawn to this very complex phenomenon. It is, moreover, impossible to regard the sentiment of the “ego” as belonging exclusively to man. Everything leads us to believe that it also exists in the other higher animals. In any case there is no metaphysical doctrine to be founded upon this exceedingly complex and very unstable sentiment. Comte is here speaking as the successor of Hume and of Cabanis. In the clearest manner he defines his opposition to Cousin’s doctrine. The latter draws the whole of philosophy from the analysis of the “ego,” Comte draws nothing from it.
He does not, however, stop to show the superiority of the positive method over theological or metaphysical method in this matter. Of what use would it be? The progress of science, in the end, gets the better of methods which have become antiquated and barren. Metaphysicians have already passed from the state of “domination” to that of “protestation.”186 And when the positive method gets a footing in an order of phenomena, there is no instance in which, sooner or later, it has not asserted its mastery over it.
II.
The psychology of Comte is connected with that of Cabanis and of Gall, without, however, any actual confusion with them. He praises Cabanis for having been one of the first to form a positive conception of intellectual and moral phenomena.187 Cabanis set himself to show that the phenomena so numerous and so varied which take place in the being who lives and feels, constantly act and react upon each other. The psychical phenomena do not escape this law. At every moment, through the medium of the nervous system, they are subject to the influence of the state of the whole body, and they make the body feel their own influence. Cabanis gives a great number of proofs of this, borrowed from the action of sex, of age, of temperament, of illness, etc. Moreover, the relation of psychical phenomena to the brain is identical with that which exists between any function whatever and its organ, for instance, between digestion and the stomach. According to Cabanis we are not necessarily materialists because we refuse to explain the functions of feeling, and the intellectual functions by means of a special principle. First causes always escape us. Here, as elsewhere, the scientific man confines himself to the observation of phenomena and to the search after their laws. On the other hand, if psychology claimed to start from the analysis of the “ego,” it would leave aside many phenomena with which our consciousness does not acquaint us, and which are psychical nevertheless. This is a fruitful remark, which will be taken up again by Maine de Biran, and which psychologists in our own time have turned to great account.
Cabanis conceived psychical facts in a positive manner, but he did not attempt to construct their science. In Comte’s opinion it is Gall who is the real founder of positive psychology. Whatever may be the value of his localisations—Comte does not think it an enduring one,—to Gall at least belongs the merit of having set the problem as it should be set, and of presenting a precise solution of it. Moreover Gall did not confine himself to localising the different faculties in different parts of the brain. His doctrine proper is preceded by an excellent criticism directed against the psychology usually received in the XVIII. century.
In order to combat Condillac, Helvetius and the ideologists, Gall takes his stand upon experience, that is to say upon mental physiology and pathology, and also upon the observation of animals. As a fact, each individual comes into the world with tendencies, with predispositions, with innate faculties. The supposed natural equality of all men is an ill-founded abstraction, since their propensities and their qualities often differ very greatly. The paradox of Helvetius who attributes the moral and intellectual inequality of men to the all powerful influence of education and of circumstances, cannot be upheld. We cannot, as we will, make just minds and upright souls. Variety of organs entails diversity of functions; the difference between men and animals, as that of men among themselves, is therefore due to anatomical and and physiological differences. Condillac’s absolute sensualism is thus refuted by facts. Moreover, if the science of psychology does not advance it is because distinctions between the faculties of the soul, (memory, imagination, judgment, etc.) have been arbitrarily established, from a metaphysical and logical point of view, which does not correspond to the real speciality of the functions.
Gall lays down the following principle as the ultimate conclusion of experience, and the fundamental basis of his doctrine of the functions of the brain:188 The dispositions of the individual soul and mind are innate and their manifestation depends upon the organisation. We must not see in this a return to the a priori method. Gall guards against reverting to the innateness of Descartes and Leibnitz. He means to speak simply of dispositions, or tendencies, or “faculties,” for instance, the faculty of love, the feeling of the just and of the unjust, ambition, the faculty of learning languages, that of comparing several judgments or ideas, of deducing consequences from them, etc. “We confine ourselves,” says Gall, “to observation.” We only consider the faculties of the soul in so far as they become phenomena for us by means of the material organs. We deny and affirm nothing except that which can be brought under judgment by experience.
Comte assents to all this. With Gall he condemns the “childish dreams” of Condillac and of his successors about transformed sensations189; with him he admits the speciality of the psychical functions, corresponding to the speciality of the cerebral organs. But he only borrows Gall’s principle. He has the strongest objections even to Gall’s psychology. Undoubtedly at the time when Gall lived, no one could have done better, and his effort deserves to be admired. But his errors, although they were inevitable, are errors none the less.
In the first place Gall was wrong in isolating the nervous system too much from the brain, which is in fact a prolongation of this system, as is proved by comparative anatomy.190 Gall considered the systems of automatic life, of voluntary motion, and of the senses, as entirely distinct from one another. He only included in the brain those nervous organs, which, at any rate in the most perfect animals, are the special organs of consciousness, of the instinctive aptitudes, of the inclinations, and of the faculties of the mind and soul. To this thesis Comte opposes the facts assembled by Cabanis, and the solidarity of all the elements in the living being. The brain can neither be isolated from the rest of the nervous system, nor the nervous system from the rest of the organism.
Again, Gall multiplies the faculties in an arbitrary manner. He had established 27 of them. Spurzheim carried this number to 35, and others have further increased it. Every phrenologist will soon create a function, and its organ, whenever it may seem opportune to him, with as much facility as ideologists and psychologists construct entities.191 These creations are nearly always extremely clumsy. Thus an innate “mathematical aptitude” has been established. Why not also a chemical, an anatomical aptitude, etc.? And this mathematical aptitude is manifested by the facility for executing calculations. But the mathematical mind, far from being an isolated and special aptitude, presents all the varieties which the human mind can offer by the different combinations of really elementary faculties. For instance, some great geometers have especially excelled by the sagacity of their inventions, others by the extent of their combinations, others again by the genius of language and the institution of signs and so on. From this point of view, well drawn up monographies of great scientific men and great artists would be extremely precious for the progress of psychology.
In conclusion, “fundamental phrenological analysis” must be reconstructed. From Gall, Comte only preserves “the impulsion.” The greater part of the localisations which Gall thought right to establish must be abandoned. But he was right in searching for them, for thus he showed science the path to be followed. Even an erroneous hypothesis on positive lines is always a service rendered in the beginnings of a science. But of Gall’s doctrine only two principles henceforth indisputable subsist. 1st, the innateness of the various fundamental dispositions, be they affective or intellectual; 2nd, the plurality of faculties distinct and independent of one another, “although effective actions usually demand their more or less complex co-operation.” These two principles are moreover the two correlative and interdependent aspects of the same conception, which is in accordance with what “common sense” has always thought of human nature. It corresponds to the division of the brain, from the anatomical point of view into a certain number of partial organs, at once independent and depending upon one another. To establish and to demonstrate the detail of this correspondence is the object of “phrenological physiology.”
III.
Comte took up the attempt where Gall had failed. But his doctrine passed through two successive forms. He himself calls attention to the importance and to the causes of this change.
In 1837, when he was writing the third volume of the Cours de philosophie positive, he still closely followed not only Gall’s general conception, but also his anatomical and physiological hypotheses. He then thought that “the doctrine deduced by Gall from the method represents the true moral and intellectual nature of man and animals with admirable fidelity.” He approved of the division of the faculties into the affective and the intellectual, the organs of the former occupying the whole of the posterior and middle regions of the brain, and the organs of the others occupying only the anterior region of the brain, that is to say, a quarter or a sixth of the cephalic mass, “which at once re-establishes the pre-eminence of the affective faculties upon a scientific basis.” He even accepted the sub-division of these faculties into inclinations and feelings, and that of the intellectual faculties into perceptive faculties and reflective faculties.
At this moment, his objections were especially directed against the excessive multiplication of the faculties, and upon the insufficiency of the anatomy of the brain which accompanied the distinction of so many faculties. He thought the anatomists were right in protesting against this method of the phrenologists who, from the supposed existence of an irreducible faculty, assume the existence of a corresponding organ in the brain. But anatomy cannot thus be treated a priori. As the aim of every biological theory is to establish an exact harmony between anatomical analysis and physiological analysis, this evidently supposes that they are not exactly modelled upon one another, and that each one of them has been worked out in a distinct manner. We must then take up the analysis of the cerebral apparatus again, provisionally setting aside all idea of function, or at least only making use of it as an auxiliary in anatomical research.192
In 1851, in the first volume of the Politique positive, Comte’s attitude is quite different. In Gall’s psychology he no longer recognises anything but what is of historical interest. His own conception of psychology is completely altered. This great change has been determined by the foundation of sociology.
Undoubtedly Gall’s merit remains very great, for he rendered a service of the first order in daring to construct a positive theory of the intellectual and moral functions. Without this theory, which at first he considered to be exact in its general lines, Comte could not have undertaken to apply the positive method to social facts, nor consequently to found his philosophy. So his gratitude to Gall is almost as great as to Condorcet, “his spiritual father.” But once sociology is founded, in looking back, Comte understands that Gall’s “cerebral theory” cannot be maintained. It resembles a provisional bridge by means of which positive philosophy passed over the interval which separates biology proper from sociology. Hardly has it reached the other side when the bridge collapses. It matters little: it suffices that, thanks to the bridge, Comte should have set foot upon the sociological ground. He can now return in all security to the study of the mental functions. “When I had founded sociology,” he says, “I understood at last that Gall’s genius had been unable to construct a real physiology of the brain, owing to the lack of a knowledge of the laws of collective evolution, which alone must furnish at once its principle and its end. From that time I felt that this task, which before I expected biologists to accomplish, belonged to the second part of my own philosophical career.”193
The psychology, which, in the Cours de philosophie positive, was essentially biological, and ended simply in sociology, becomes, in the Politique positive essentially sociological, and is only secondarily biological. From 1846 Comte became conscious of this new orientation of his thought, and, during the five years which follow, he never ceases working at his “cerebral table.”
At first, he no longer demands an anatomical study parallel to the analysis of the mental functions, and independent of it. He intends, henceforth, to determine these functions outside all anatomical research. “The logical principle of this construction consists, for me, in its subjective institution.” He systematically subordinates anatomy to physiology, and he henceforth conceives the determination of the cerebral organs as the complement, and even as the result, of the positive study of the intellectual and moral functions. At bottom, “this subject has never allowed of any other method but the subjective, well or ill employed.” It has been equally used by the disciples of Gall and by his adversaries. What psychology has lacked up to the present is, not exact localisations but a sufficiently deep analysis of intellectual and moral phenomena. And as a matter of fact it was impossible to treat this problem well, so long as we ignored the laws of sociology, “which alone is capable of dealing with these noble functions.”194
Thus, in order to determine the elementary faculties, those which are irreducible, and which by their co-operation produce the complex phenomena which are apprehended by consciousness, the method must be at once subjective and sociological. For the subject which we must analyse is not the individual consciousness, of which the study is too inaccessible, and whose life is too short: it is the universal subject, humanity, “the case of the species being alone sufficiently developed to characterise the various functions.” To this analysis, as a system of control, will be joined the observation of animals. Indeed, all our innate dispositions belong also to the other superior animals. If then the study of man should seem to establish elementary, moral, or even intellectual functions, of which we see no trace in these animals, by this alone we should consider that the analysis has been imperfect, and that complex results have been considered as irreducible. “Sociological inspiration controlled by zoological appreciation: such is the general principle of the positive theory of the soul.”195
By this method Comte obtains 18 irreducible faculties, of which 10 are representative of the heart, 5 of the mind, and 3 of the character. To each of these he assigns a special organ. He places the organ of the heart in the posterior portion of the brain and in the cerebellum, the organs of the mind in the anterior portion of the brain, and those of character in the intermediary region. Anatomists are free to verify a posteriori the separation of the 18 elements which Comte distinguished a priori in the cerebral apparatus. The existence of these organs, in any case, appears to him to be sufficiently demonstrated, and anatomical determination is not very important. We might confine ourselves to the specification of the number and the situation of the organs, which we have deduced from the number and relations of the elementary functions. It would not be necessary for us to know their shape or their size. The utility of cerebral localisations resembles that which geometers draw from curves for the better consideration of equations.196 The organ is simply the static equivalent of the function of the soul. It suffices for us to know its existence and its position so as to situate in it all the relations of the function itself, so to speak. It plays the part of a schematic drawing.
So, the theory of the brain and of the soul is no longer “simultaneous.” In fact, the theory of the soul is first constructed by a subjective and independent method and without any consideration of the disposition of the cerebral apparatus. This disposition is deduced, afterwards, from the theory of the soul, once it is established.
Returning then to Gall’s psychology, Comte can explain its defects to himself. Gall had “oscillated between subjective inspiration and objective tendencies,” without adopting a systematic plan. There has not been any very great disadvantage in this empirical fluctuation in what concerns the theory of the affective functions. Without a doubt, Gall had established an ill-founded distinction between the inclinations and the feelings. But he could not be mistaken concerning the fundamental inclinations of human nature. In default of the true method, he was supported on this point by common wisdom, and by the observation of animals. It is on the subject of the intellectual functions that he is entirely wrong, because here this twofold help failed him, and nothing, in this case, filled the place of the true method which was then unknown. In order to discover the static and dynamic laws of the intellect, it was necessary to abandon the biological point of view. To Gall’s theory Comte then substitutes a new classification of the intellectual functions. He distinguishes between the faculties of conception and the faculties of expression. He indicates the relations of the intellectual functions proper with the affective functions and the functions of motion. He makes us apprehend the very intimate relations which connect desire and will. Finally, to determine the fundamental intellectual functions, he takes into account the historical evolution of the human species.
It does not enter into the purpose of this work to set forth Comte’s theory in detail, and to examine the eighteen irreducible faculties of the cerebral table one by one. But the systematic character of the doctrine does not prevent us from taking up a certain number of interesting and deep psychological views in it. To limit ourselves to a few examples, Comte drew imitation near to habit, and he brought habit itself back “to the great cosmological law of persistence,” which, in the vital order is modified by the intermittance of phenomena.197 He remarked that attention is never produced without an affective phenomenon upon which it depends.198 He also indicated the distinction between strong states and weak states, and the “reduction” of images by actual perceptions. “If our images could offer as much intensity, he says, as our external sensations, our mental state would not allow of any consistency. The appreciation of what is without would be troubled by this conflict with what is within....” Hence a theory of hallucination and insanity.199
The theory of perception which Comte opposes to the abstract sensualism of the ideologists is allied to his general conception of the relations between the subject and the object. Our internal operations are never anything but the direct or indirect prolongation of our external impressions. But “reciprocally, the latter are always complicated by the others, even in the most elementary cases.” The sensation, which appears simple, is already the result of a very complex combination.200 For no sensations are really perceived except after reiterated impressions. If the mind is ever passive, it can only be the first time. For the second, it is already prepared by the preceding one, combined with the whole of previous acquisitions. And Comte insists upon “the habitual participation of reasoning in the operations which are attributed to sensation alone.” The activity belonging to the mind enters into all its actions, even the smallest of them.
Mental pathology scarcely exists, owing to the lack of the scientific spirit among specialists for the diseases of the mind. Still if Broussais’ principle be true, that is to say, if morbid phenomena are produced according to the same laws which govern normal phenomena, what advantage might not scientific men derive from the observation of mental diseases? They are privileged cases which nature supplies for them, real experiments, where that which is inseparable in the normal state appears disassociated. What light might be thrown by this means upon many physiological and even anatomical questions, in particular in what concerns the sentiment of the ego (diseases of personality, aboulia, etc.), and the faculties of expression, isolated from the faculties of conception (diseases of speech).
Animal psychology would not be less instructive. All the affective and intellectual faculties are common to men and higher animals, save perhaps the highest intellectual aptitudes. Even this exception is a doubtful one, if without prejudice we compare the actions of the highest animals with those of the least developed savages. We should study the habits and the mind of wild animals. We should observe the changes which are produced in them by domestication. Here again almost everything has to be done afresh.201
IV.
In spite of whatever may have been said, Comte then has a psychology. And, what is more, this psychology is in a sense not far removed from that of the Scottish school and of the Eclectics although he so much fought against their methods. The points of contact are numerous and important. In both doctrines the psychical phenomena are referred to faculties and these are represented as “dispositions,” innate “properties.” In both, the essential psychological problem appears to be the determination of the number and the relations of these faculties, whose action variously combined produces psychical phenomena: before everything, it is a question of not considering as an elementary faculty that which as a matter of fact results from the combination of several faculties, or inversely. Finally in both, it is claimed to establish this doctrine of the innate faculties upon the observation of human nature.
Comte himself had seen that, at any rate in the case of Condillac’s criticism, he was in accordance with the eclectics. On this point he only refused to grant them originality. According to him they merely popularised, in obscure and emphatic declamations, what physiologists like Charles Bonnet, Cabanis, and chiefly Gall and Spurzheim had long before stated on this subject in a far clearer and especially in a far more exact manner. For his part Garnier, the author of the TraitÉ des FacultÉs de l’Âme had clearly seen the relations of eclecticism to Gall’s doctrine, and had studied them in a work entitled De la PhrÉnologie et de la Psychologie comparÉes which appeared in 1839.
Why then does Comte attack the eclectics with such persistence and such violence, if, indeed, the results of his psychology are not very far removed from what they say?—It is because in reality, beneath the apparent resemblance of doctrine, a difference of method as serious as can be conceived is concealed. For Cousin, and especially for the Cousin we know before 1830, psychology is not an end in itself. It is a means which he uses to rise to the study of being in itself and of the Absolute. The “ego” which he analyses is independent of the organism. This is what Comte condemns as a retrogression. “Some men, not recognizing the present and irrevocable direction of the human mind, have endeavoured for ten years to transplant German metaphysics into our midst, and to constitute, under the name of psychology, a so-called science entirely independent of physiology, superior to it, and to which should exclusively belong the study of moral phenomena.”202 And this attempt at reaction takes place at the very moment when the works of Cabanis and of Gall have brought this study upon the positive path!
It is needless to say that, in Comte’s system, psychical phenomena are subordinated, as far as their conditions of existence are concerned, to all the orders of more general natural phenomena. Comte should then have followed Cabanis and Gall, as a matter of course. But he thought that to establish the science of the “transcendent functions,” the biological point of view was insufficient. In this case anatomical considerations are only a kind of reduplication and transcription of physiological considerations. As Maine de Biran said, in terms curiously like Comte’s, “a distinction of places assigned to the exercise of each faculty must necessarily be itself referred to another pre-established division of the faculties.... Hypothesis thus grafted upon hypothesis of a different order would not much contribute to throw light upon the analysis of our intellectual functions.”203 Only, instead of appealing, like Maine de Biran, to reflection, Comte rises from the biological to the sociological point of view He recognises that the subjective method alone is suitable for the science of psychical phenomena, but, in place of the metaphysical subjective method, by means of which the “ego” is deluded into the belief that it analyses its operations, and grasps its own activity, he will make use of the positive subjective method. The subject which he will analyse will be the human mind, or better, the human soul considered in its continuous evolution, that is to say in its religions, in its sciences, in its philosophy, in its language and in its art. Here is matter for a psychology which will no longer be chimerical, but real, which will be positive, in a word, like the biology upon which it depends and of which it is the fulfilment.
If we leave aside the conception of the “faculties” which Comte accepted rather hastily at the hands of the Scottish school and of Gall, and the “cerebral table” which he believed to be once for all constructed, his psychology contained more than one important and fertile seed. To the eclectic psychology, which is not positive, Comte substituted two sciences which are such. In the first place, an experimental science of the psychical phenomena studied in their relation to their organic conditions: it is the physiological psychology of which no one to-day questions the legitimacy. Then, by the introduction of the sociological point of view, Comte opened the way to a whole series of studies which begin to be developed, (social psychology, ethnical psychology, psychology of the masses, etc). It is often said that sociological laws have their foundation in psychological laws. But the reverse is no less true. The psychological laws, at least the mental and moral laws, are, at the same time, sociological laws, since they are only revealed in the study of the intellectual history of the human species. “We must not explain humanity by man, but man by humanity.” To the “?????? sea?t??” of ancient psychology, the positive method substitutes this precept: “To know yourself, know history.” Man only becomes conscious of himself, when he becomes aware of his place in the evolution of Humanity.
