These are not degenerate days. We have still strong thinkers amongst us; men of untiring perseverance, who flinch before no difficulties, who never hide the knot which their readers are only too willing that they should let alone; men who dare write what the ninety-nine out of every hundred will pronounce a dry book; who pledge themselves, not to the public, but to their subject, and will not desert it till their task is completed. One of this order is Mr John Stuart Mill. The work he has now presented to the public, we deem to be, after its kind, of the very highest character, every where displaying powers of clear, patient, indefatigable thinking. Abstract enough it must be allowed to be, calling for an unremitted attention, and yielding but little, even in the shape of illustration, of lighter and more amusing matter; he has taken no pains to bestow upon it any other interest than what searching thought and lucid views, aptly expressed, ought of themselves to create. His subject, indeed—the laws by which human belief and the inquisition of truth are to be governed and directed—is both of that extensive and fundamental character, that it would be treated with success only by one who knew how to resist the temptations to digress, as well as how to apply himself with vigour to the solution of the various questions that must rise before him.

Such is the manly and modest estimate which the author makes of his own labours, and the work fully bears out the character here given of it. No one capable of receiving pleasure from the disentanglement of intricacies, or the clear exposition of an abstruse subject; no one seeking assistance in the acquisition of distinct and accurate views on the various and difficult topics which these volumes embrace—can fail to read them with satisfaction and with benefit.

To give a full account—to give any account—of a work which traverses so wide a field of subject, would be here a futile attempt; we should, after all our efforts, merely produce a laboured and imperfect synopsis, which would in vain solicit the perusal of our readers. What we purpose doing, is to take up, in the order in which they occur, some of the topics on which Mr Mill has thrown a new light, or which he has at least invested with a novel interest by the view he has given of them. And as, in this selection of topics, we are not bound to choose those which are most austere and repulsive, we hope that such of our readers as are not deterred by the very name of logic, will follow us with some interest through the several points of view, and the various extracts we shall present to them.

The Syllogism.—The logic of Induction, as that to which attention has been least devoted, which has been least reduced to systematic form, and which lies at the basis of all other modes of reasoning, constitutes the prominent subject of these volumes. Nevertheless, the old topic of logic proper, or deductive reasoning, is not omitted, and the first passage to which we feel bound, on many accounts, to give our attention, is the disquisition on the syllogism.

Fortunately for us it is not necessary, in order to convey the point of our author's observations upon this head, to afflict our readers with any dissertation upon mode or figure, or other logical technicalities. The first form or figure of the syllogism (to which those who have not utterly forgotten their scholastic discipline will remember that all others may be reduced) is familiar to every one, and to this alone we shall have occasion to refer.

Who has not met—what young lady even, though but in her teens, has not encountered some such charming triplet as this, which looks so like verse at a distance, but, like some other compositions, approximates nothing the more on this account to poetry? Who has not learnt from such examples what is a major, what a middle term, and what the minor or conclusion?

As no one, in the present day, advises the adoption, in our controversies, of the syllogistic forms of reasoning, it is evident that the value of the syllogism must consist, not in its practical use, but in the accurate type which it affords of the process of reasoning, and in the analysis of that process which a full understanding of it renders necessary. Such an analysis supplies, it is said, an excellent discipline to the mind, whilst an occasional reference to the form of the syllogism, as a type or model of reasoning, insures a steadiness and pertinency of argument. But is the syllogism, it has been asked, this veritable type of our reasoning? Has the analysis which would explain it to be such, been accurately conducted?

Several of our northern metaphysicians, it is well known—as, for example, Dr Campbell and Dugald Stewart—have laid rude hands upon the syllogism. They have pronounced it to be a vain invention. They have argued that no addition of knowledge, no advancement in the acquisition of truth, no new conviction, can possibly be obtained through its means, inasmuch as no syllogism can contain any thing in the conclusion which was not admitted, at the outset, in the first or major proposition. The syllogism always, say they, involves a petitio principii. Admit the major, and the business is palpably at an end; the rest is a mere circle, in which one cannot advance, but may get giddy by the revolution. According to the exposition of logicians themselves, we simply obtain by our syllogism, the privilege of saying that, in the minor, of some individual of a class, which we had said, in the major, already of the whole class.

Archbishop Whately, our most distinguished expositor and defender of the Aristotelian logic, meets these antagonists with the resolute assertion, that their objection to the syllogism is equally valid against all reasoning whatever. He does not deny, but, on the contrary, in common with every logician, distinctly states, that whatever is concluded in the minor, must have been previously admitted in the major, for in this lies the very force and compulsion of the argument; but he maintains that the syllogism is the true type of all our reasoning, and that therefore to all our reasoning, the very same vice, the very same petitio principii, may be imputed. The syllogism, he contends, (and apparently with complete success,) is but a statement in full of what takes place mentally even in the most rapid acts of reasoning. We often suppress the major for the sake of brevity, but it is understood though not expressed; just as in the same manner as we sometimes content ourselves with merely implying the conclusion itself, because it is sufficiently evident without further words. If any one should so far depart from common sense as to question the mortality of some great king, we should think it sufficient to say for all argument—the king is a man!—virtually implying the whole triplet above mentioned:—

"In pursuing the supposed investigation, (into the operation of reasoning,)" says Archbishop Whately, "it will be found that every conclusion is deduced, in reality, from two other propositions, (thence called Premisses;) for though one of these may be and commonly is suppressed, it must nevertheless be understood as admitted, as may easily be made evident by supposing the denial of the suppressed premiss, which will at once invalidate the argument; e.g. if any one, from perceiving that 'the world exhibits marks of design,' infers that 'it must have had an intelligent author,' though he may not be aware in his own mind of the existence of any other premiss, he will readily understand, if it be denied that 'whatever exhibits marks of design must have had an intelligent author,' that the affirmative of that proposition is necessary to the solidity of the argument. An argument thus stated regularly and at full length, is called a syllogism; which, therefore, is evidently not a peculiar kind of argument, but only a peculiar form of expression, in which every argument may be stated."—Whately's Logic, p. 27.

"It will be found," he continues, "that all valid arguments whatever may be easily reduced to such a form as that of the foregoing syllogisms; and that consequently the principle on which they are constructed is the Universal Principle of reasoning. So elliptical, indeed, is the ordinary mode of expression, even of those who are considered as prolix writers,—i.e. so much is implied and left to be understood in the course of argument, in comparison of what is actually stated, (most men being impatient, even to excess, of any appearance of unnecessary and tedious formality of statement,) that a single sentence will often be found, though perhaps considered as a single argument, to contain, compressed into a short compass, a chain of several distinct arguments. But if each of these be fully developed, and the whole of what the author intended to imply be stated expressly, it will be found that all the steps, even of the longest and most complex train of reasoning, may be reduced into the above form."—P. 32.

That it is not the office of the syllogism to discover new truths, our logician fully admits, and takes some pains to establish. This is the office of "other operations of mind," not unaccompanied, however, with acts of reasoning. Reasoning, argument, inference, (words which he uses as synonymous,) have not for their object our advancement in knowledge, or the acquisition of new truths.

"Much has been said," says Archbishop Whately, in another portion of his work, "by some writers, of the superiority of the inductive to the syllogistic methods of seeking truth, as if the two stood opposed to each other; and of the advantage of substituting the Organon of Bacon for that of Aristotle, &c. &c., which indicates a total misconception of the nature of both. There is, however, the more excuse for the confusion of thought which prevails on this subject, because eminent logical writers have treated, or at least have appeared to treat, of induction as a kind of argument distinct from the syllogism; which, if it were, it certainly might be contrasted with the syllogism: or rather the whole syllogistic theory would fall to the ground, since one of the very first principles it establishes, is that all reasoning, on whatever subject, is one and the same process, which may be clearly exhibited in the form of syllogisms.

"This inaccuracy seems chiefly to have arisen from a vagueness in the use of the word induction; which is sometimes employed to designate the process of investigation and of collecting facts, sometimes the deducing an inference from those facts. The former of these processes (viz. that of observation and experiment) is undoubtedly distinct from that which takes place in the syllogism; but then it is not a process of argumentation: the latter again is an argumentative process; but then it is, like all other arguments, capable of being syllogistically expressed."—P. 263.

"To prove, then, this point demonstratively, (namely, that it is not by a process of reasoning that new truths are brought to light,) becomes on these data perfectly easy; for since all reasoning (in the sense above defined) may be resolved into syllogisms; and since even the objectors to logic make it a subject of complaint, that in a syllogism the premises do virtually assert the conclusion, it follows at once that no new truth (as above defined) can be elicited by any process of reasoning.

"It is on this ground, indeed, that the justly celebrated author of the Philosophy of Rhetoric objects to the syllogism altogether, as necessarily involving a petitio principii; an objection which, of course, he would not have been disposed to bring forward, had he perceived that, whether well or ill founded, it lies against all arguments whatever. Had he been aware that the syllogism is no distinct kind of argument otherwise than in form, but is, in fact, any argument whatever stated regularly and at full length, he would have obtained a more correct view of the object of all reasoning; which is merely to expand and unfold the assertions wrapt up, as it were, and implied in those with which we set out, and to bring a person to perceive and acknowledge the full force of that which he has admitted; to contemplate it in various points of view; to admit in one shape what he has already admitted in another, and to give up and disallow whatever is inconsistent with it."—P. 273.

Now, what the Archbishop here advances appears convincing; his position looks impregnable. The syllogism is not a peculiar mode of reasoning, (how could it be?)—if any thing at all, it must be a general formula for expressing the ordinary act of reasoning—and he shows that the objections made by those who would impugn it, may be levelled with equal justice against all ratiocination whatever. But then this method of defending the syllogism, (to those of us who have stood beside, in the character of modest enquirers, watching the encounter of keen wits,) does but aggravate the difficulty. Is it true, then, that in every act of reasoning, we do but conclude in one form, what, the moment before, we had stated in another? Are we to understand that such is the final result of the debate? If so, this act of reasoning appears very little deserving of that estimation in which it has been generally held. The great prerogative of intelligent beings (as it has been deemed,) grants them this only—to "admit in one shape what they had already admitted in another."

From the dilemma in which we are here placed, the Archbishop by no means releases, or attempts to release us: he seems (something too much after the manner and disposition generally attributed to masters in logic-fence,) to have rested satisfied with foiling his opponents in their attack upon the exact position he had bound himself to defend. He saves the syllogism; what becomes, in the controversy, of poor human reason itself, is not his especial concern—it is as much their business as his. You do not, more than I, he virtually says to his opponents, intend to resign all reasoning whatever as a mere inanity; I prove, for my part, that all reasoning is capable of being put into a syllogistic form, and that your objection, if valid against the syllogism, is equally valid against all ratiocination. You must therefore either withdraw your objection altogether, or advance it at your peril; the difficulty is of your making, you must solve it as you can. Gentlemen, you must muzzle your own dog.

In this posture of affairs the author of the present work comes to the rescue. He shall speak in his own words. But we must premise, that although we do not intend to stint him in our quotation—though we wish to give him all the sea-room possible; yet, for a full development of his views, we must refer the reader to his volumes themselves. There are some disquisitions which precede the part we are about to quote from, which, in order to do complete justice to the subject, ought to find a place here, as well as in the author's work—but it is impossible.

By this explanation we are released from the dilemma into which the syllogistic and non-syllogistic party had together thrown us. We can acknowledge that the process of reason can be always exhibited in the form of a syllogism, and yet not be driven to the strange and perplexing conclusion that our reasoning can never conduct us to a new truth, never lead us further than to admit in one shape what we had already admitted in another. We have, or may have, it is true, a major in all our ratiocination, implied, if not expressed, and are so far syllogistic; but then the real premiss from which we reason is the amount of experience on which that major was founded, to which amount of experience we, in fact, made an addition in our minor, or conclusion. But while we accept this explanation, and are grateful for the deliverance it works for us, we must also admit, (and we are not aware that Mr Mill would controvert this admission,) that there is a large class of cases in which our reasoning betrays no reference to this anterior experience, and where the usual explanation given by teachers of logic is perfectly applicable; cases where our object is, not the discovery of truth for ourselves, but to convince another of his error, by showing him that the proposition, which in his blindness or prejudice he has chosen to contradict, is part and parcel of some other proposition to which he has given, and is at all times ready to give, his acquiescence. In such cases, we frequently content ourselves with throwing before him this alternative—refuse your major, to which you have again and again assented, or accept, as involved in it, our minor proposition, which you have persisted in controverting.

It will have been gathered from the foregoing train of observation, that, in direct contradistinction to Archbishop Whately, who had represented induction (so far as it consisted of an act of ratiocination) as resolvable into deductive and syllogistic reasoning, our author has resolved the syllogism, and indeed all deductive reasoning whatever, ultimately into examples of induction. In doing this, he is encountered by a metaphysical notion very prevalent in the present day, which lies across his path, and which he has to remove. We allude to the distinction between contingent and necessary truths; it being held by many philosophical writers that all necessary and universal truths owe their origin, not to experience (except as occasion of their development,) and not, consequently, to the ordinary process of induction, but flow from higher sources—flow immediately from some supreme faculty to which the name of reason has by some been exclusively appropriated, in order to distinguish it from the understanding, the faculty judging according to sense. We will pause a while upon this topic.

Contingent and Necessary Truths.—Those who have read Mr Whewell's treatise on the Philosophy of the Inductive Sciences, will remember that there is no topic which that author labours more sedulously to inculcate than this same distinction between contingent and necessary truths; and it is against his statement of the doctrine in question, that Mr Mill directs his observations. Perhaps the controverted tenets would have sustained a more equal combat under the auspices of a more practised and more complete metaphysician than Mr Whewell; but a difficulty was probably experienced in finding a statement in any other well-known English author full and explicit. Referring ourselves to Mr Whewell's volumes for an extract, in order to give the distinction here contended against the advantage of an exposition in the words of one who upholds it, we are embarrassed by the number which offer themselves. From many we select the following statement:—

"Experience," says Mr Whewell, "must always consist of a limited number of observations. And, however numerous these may be, they can show nothing with regard to the infinite number of cases in which the experiment has not been made. Experience, being thus unable to prove a fact to be universal, is, as will readily be seen, still more incapable of proving a fact to be necessary. Experience cannot, indeed, offer the smallest ground for the necessity of a proposition. She can observe and record what has happened; but she cannot find, in any case, or in any accumulation of cases, any reason for what must happen. She may see objects side by side, but she cannot see a reason why they must be ever side by side. She finds certain events to occur in succession; but the succession supplies, in its occurrence, no reason for its recurrence. She contemplates external objects; but she cannot detect any internal bond which indissolubly connects the future with the past, the possible with the real. To learn a proposition by experience, and to see it to be necessarily true, are two altogether different processes of thought.

"But it may be said, that we do learn, by means of observation and experience, many universal truths; indeed, all the general truths of which science consists. Is not the doctrine of universal gravitation learned by experience? Are not the laws of motion, the properties of light, the general properties of chemistry, so learned? How, with these examples before us, can we say that experience teaches no universal truths?

"To this we reply, that these truths can only be known to be general, not universal, if they depend upon experience alone. Experience cannot bestow that universality which she herself cannot have, and that necessity of which she has no comprehension. If these doctrines are universally true, this universality flows from the ideas which we apply to our experience, and which are, as we have seen, the real sources of necessary truth. How far these ideas can communicate their universality and necessity to the results of experience, it will hereafter be our business to consider. It will then appear, that when the mind collects from observation truths of a wide and comprehensive kind, which approach to the simplicity and universality of the truths of pure science; she gives them this character by throwing upon them the light of her own fundamental ideas."—Whewell, Vol. I. p. 60.

Accordingly, Mr Whewell no sooner arrives at any truth which admits of an unconditional positive statement—a statement defying all rational contradiction—than he abstracts it from amongst the acquisitions of experience, and throwing over it, we suppose, the light of these fundamental ideas, pronounces it enrolled in the higher class of universal and necessary truths. The first laws of motion, though established through great difficulties against the most obstinate preconceptions, and by the aid of repeated experiments, are, when surveyed in their present perfect form, proclaimed to be, not acquisitions of experience, but truths emanating from a higher and more mysterious origin.[2]

This distinction, which assigns a different mental origin to truths, simply because (from the nature of the subject-matter, as it seems to us) there is a difference with regard to the sort of certainty we feel of them, has always appeared to us most unphilosophical. It is admitted that we arrive at a general proposition through experience; there is no room, therefore, for quibbling as to the meaning of the term experience—it is understood that when we speak of a truth being derived from experience, we imply the usual exercise of our mental faculties; it is the step from a general to a universal proposition which alone occasions this perplexing distinction. The dogma is this—that experience can only teach us by a limited number of examples, and therefore can never establish a universal proposition. But if all experience is in favour of a proposition—if no experience has occurred even to enable the imagination to conceive its opposite, what more can be required to convert the general into a universal proposition?

Strange to say, the attribution of these characteristics of universality and necessity, becomes, amongst those who loudly insist upon the palpable nature of the distinction we are now examining, a matter of controversy; and there are a class of scientific truths, of which it is debated whether they are contingent or necessary. The only test that they belong to the latter order is, the impossibility of conceiving their opposites to be the truth; and it seems that men find a great difference in their powers of conception, and that what is impossible with one is possible with another. But (wisely, too) passing this over, and admitting that there is a distinction (though a very ill-defined one) between the several truths we entertain of this nature; namely, that some we find it impossible, even in imagination, to contradict, whilst of others we can suppose it possible that they should cease to be truths—does it follow that different faculties of the mind are engaged in the acquisition of them? Does nothing depend on the nature of the subject itself? "That two sides of a triangle," says Mr Whewell, "are greater than the third, is a universal and necessary geometrical truth; it is true of all triangles; it is true in such a way that the contrary cannot be conceived. Experience could not prove such a proposition." Experience is allowed to prove it of this or that triangle, but not as an inseparable property of a triangle. We are at a loss to perceive why the same faculties of the mind that can judge, say of the properties of animal life, of organized beings, cannot judge of the properties of a figure—properties which must immediately be conceived to exist the moment the figure is presented to the imagination. We say, for instance, of any animal, not because it is this or that animal, a sheep or an ox, but simply as animal, that it must sustain itself by food, by the process of assimilation. This, however, is merely a contingent truth, because it is in our power to conceive of organized beings whose substance shall not wear away, and consequently shall not need perpetual restoration. But what faculty of the mind is unemployed here that is engaged in perceiving the property of a triangle, that as triangle, it must have two sides greater than the third? The truths elicited in the two cases have a difference, inasmuch as a triangle differs from an animal in this, that it is impossible to conceive other triangles than those to which your truth is applicable, and therefore the proposition relating to the triangle is called a necessary truth. But surely this difference lies in the subject-matter, not in the nature of our mental faculties.

But we had not intended to interpose our own lucubrations in the place of those of Mr Mill.

Mr Mill does not deny that there exists a distinction, as regards ourselves, between certain truths (namely, that of some, we cannot conceive them to be other than truths,) but he sets no value on this distinction, inasmuch as there is no proof that it has its counterpart in things themselves; the impossibility of a thing being by no means measured by our inability to conceive it. And we may observe, that Mr Whewell, in consistency with the metaphysical doctrine upon space and time which he has borrowed from Kant, ought, under another shape, to entertain a similar doubt as to whether this distinction represent any real distinction in the nature of things. He considers, with Kant, that space is only that form with which the human mind invests things—that it has no other than this merely mental existence—is purely subjective. Presuming, therefore, that the mind is, from its constitution, utterly and for ever unable to conceive the opposite of certain truths, (those, for instance, of geometry;) yet as the existence of space itself is but a subjective truth, it must follow that all other truths relating to it are subjective also. The mind is not conversant with things in themselves, in the truths even of geometry; nor is there any positive objective truth in one department of science more than another. Mr Whewell, therefore, though he advocates this distinction between necessary and contingent truth with a zeal which would seem to imply that something momentous, or of peculiar interest, was connected with it, can advocate it only as a matter of abstract metaphysical science. He cannot participate in that feeling of exaltation and mystery which has led many to expatiate upon a necessary and absolute truth which the Divine Power itself cannot alter, which is equally irresistible, equally binding and compulsory, with God as with man. Of this spirit of philosophical enthusiasm Mr Whewell cannot partake. Space and Time, with all their properties and phenomena, are but recognized as the modes of thought of a human intelligence.

We have marked a number of passages for annotation and extract—a far greater number than we can possibly find place for alluding to. One subject, however, which lies at the very basis of all our science, and which has received a proportionate attention from Mr Mill, must not be amongst those which are passed over. We mean the law of Causation. What should be described as the complete and adequate notion of a cause, we need not say is one of the moot points of philosophy. According to one school of metaphysicians, there is in our notion of cause an element not derived from experience, which, it is confessed on all hands, can teach us only the succession of events. Cause, with them, is that invisible power, that mysterious bond, which this succession does but signify: with other philosophers this succession constitutes the whole of any intelligible notion we have of cause. The latter opinion is that of Mr Mill; at the same time the question is one which lies beyond or beside the scope of his volumes. He is concerned only with phenomena, not with the knowledge (if such there be) of "things in themselves;" that part, therefore, of our idea of cause which, according to all systems of philosophy, is won from experience, and concerns phenomena alone, is sufficient for his purpose. That every event has a cause, that is, a previous and uniformly previous event, and that whatever has happened will, in the like circumstances, happen again—these are the assumptions necessary to science, and these no one will dispute.

Mr Mill has made a happy addition to the usual definition of cause given by that class of metaphysicians to which he himself belongs, and which obviates a plausible objection urged against it by Dr Reid and others. These have argued, that if cause be nothing more than invariable antecedence, then night may be said to be the cause of day, for the one invariably precedes the other. Day does succeed to night, but only on certain conditions—namely, that the sun rise. "The succession," observes Mr Mill, "which is equivalent and synonymous to cause, must be not only invariable but unconditional. We may define, therefore," says our author, "the cause of a phenomenon to be the antecedent, or the concurrence of antecedents, upon which it is invariably and unconditionally consequent."—Vol. I. p. 411.

A dilemma may be raised of this kind. The universality of the law of causation—in other words, the uniform course of nature—is the fundamental principle on which all induction proceeds, the great premise on which all our science is founded. But if this law itself be the result only of experience, itself only a great instance of induction, so long as nature presents cases requiring investigation, where the causes are unknown to us, so long the law itself is imperfectly established. How, then, can this law be a guide and a premiss in the investigations of science, when those investigations are necessary to complete the proof of the law itself? How can this principle accompany and authorise every step we take in science, which itself needs confirmation so long as a process of induction remains to be performed? Or how can this law be established by a series of inductions, in making which it has been taken for granted?

Objections which wear the air of a quibble have often this advantage—they put our knowledge to the test. The obligation to find a complete answer clears up our own conceptions. The observations which Mr Mill makes on this point, we shall quote at length. They are taken from his chapter on the Evidence of the Law of Universal Causation; the views in which are as much distinguished for boldness as for precision.

After having said, that in all the several methods of induction the universality of the law of causation is assumed, he continues:—

"But is this assumption warranted? Doubtless (it may be said) most phenomena are connected as effects with some antecedent or cause—that is, are never produced unless some assignable fact has preceded them; but the very circumstance, that complicated processes of induction are sometimes necessary, shows that cases exist in which this regular order of succession is not apparent to our first and simplest apprehension. If, then, the processes which bring these cases within the same category with the rest, require that we should assume the universality of the very law which they do not at first sight appear to exemplify, is not this a real petitio principii? Can we prove a proposition by an argument which takes it for granted? And, if not so proved, on what evidence does it rest?

"For this difficulty, which I have purposely stated in the strongest terms it would admit of, the school of metaphysicians, who have long predominated in this country, find a ready salvo. They affirm that the universality of causation is a truth which we cannot help believing; that the belief in it is an instinct, one of the laws of our believing faculty. As the proof of this they say, and they have nothing else to say, that every body does believe it; and they number it among the propositions, rather numerous in their catalogue, which may be logically argued against, and perhaps cannot be logically proved, but which are of higher authority than logic, and which even he who denies in speculation, shows by his habitual practice that his arguments make no impression on himself.

"I have no intention of entering into the merits of this question, as a problem of transcendental metaphysics. But I must renew my protest against adducing, as evidence of the truth of a fact in external nature, any necessity which the human mind may be conceived to be under of believing it. It is the business of human intellect to adapt itself to the realities of things, and not to measure those realities by its own capacities of comprehension. The same quality which fits mankind for the offices and purposes of their own little life, the tendency of their belief to follow their experience, incapacitates them for judging of what lies beyond. Not only what man can know, but what he can conceive, depends upon what he has experienced. Whatever forms a part of all his experience, forms a part also of all his conceptions, and appears to him universal and necessary, though really, for aught he knows, having no existence beyond certain narrow limits. The habit, however, of philosophical analysis, of which it is the surest effect to enable the mind to command, instead of being commanded by, the laws of the merely passive part of its own nature, and which, by showing to us that things are not necessarily connected in fact because their ideas are connected in our minds, is able to loosen innumerable associations which reign despotically over the undisciplined mind; this habit is not without power even over those associations which the philosophical school, of which I have been speaking, regard as connate and instinctive. I am convinced that any one accustomed to abstraction and analysis, who will fairly exert his faculties for the purpose, will, when his imagination has once learned to entertain the notion, find no difficulty in conceiving that in some one, for instance, of the many firmaments into which sidereal astronomy now divides the universe, events may succeed one another at random, without any fixed law; nor can any thing in our experience, or in our mental nature, constitute a sufficient, or indeed any, reason for believing that this is nowhere the case. The grounds, therefore, which warrant us in rejecting such a supposition with respect to any of the phenomena of which we have experience, must be sought elsewhere than in any supposed necessity of our intellectual faculties.

"As was observed in a former place, the belief we entertain in the universality, throughout nature, of the law of cause and effect, is itself an instance of induction; and by no means one of the earliest which any of us, or which mankind in general, can have made. We arrive at this universal law by generalisation from many laws of inferior generality. The generalising propensity which, instinctive or not, is one of the most powerful principles of our nature, does not indeed wait for the period when such a generalisation becomes strictly legitimate. The mere unreasoning propensity to expect what has been often experienced, doubtless led men to believe that every thing had a cause, before they could have conclusive evidence of that truth. But even this cannot be supposed to have happened until many cases of causation, or, in other words, many partial uniformities of sequence, had become familiar. The more obvious of the particular uniformities suggest and prove the general uniformity; and that general uniformity, once established, enables us to prove the remainder of the particular uniformities of which it is made up.***

"With respect to the general law of causation, it does appear that there must have been a time when the universal prevalence of that law throughout nature could not have been affirmed in the same confident and unqualified manner as at present. There was a time when many of the phenomena of nature must have appeared altogether capricious and irregular, not governed by any laws, nor steadily consequent upon any causes. Such phenomena, indeed, were commonly, in that early stage of human knowledge, ascribed to the direct intervention of the will of some supernatural being, and therefore still to a cause. This shows the strong tendency of the human mind to ascribe every phenomenon to some cause or other; but it shows also that experience had not, at that time, pointed out any regular order in the occurrence of those particular phenomena, nor proved them to be, as we now know that they are, dependent upon prior phenomena as their proximate causes. There have been sects of philosophers who have admitted what they termed Chance as one of the agents in the order of nature by which certain classes of events were entirely regulated; which could only mean that those events did not occur in any fixed order, or depend upon uniform laws of causation.***

"The progress of experience, therefore, has dissipated the doubt which must have rested upon the universality of the law of causation, while there were phenomena which seemed to be sui generis; not subject to the same laws with any other class of phenomena, and not as yet ascertained to have peculiar laws of their own. This great generalisation, however, might reasonably have been, as it in fact was by all great thinkers, acted upon as a probability of the highest order, before there were sufficient grounds for receiving it as a certainty. For, whatever has been found true in innumerable instances, and never found to be false after due examination in any, we are safe in acting upon as universal provisionally, until an undoubted exception appears; provided the nature of the case be such that a real exception could scarcely have escaped our notice. When every phenomenon that we ever knew sufficiently well to be able to answer the question, had a cause on which it was invariably consequent, it was more rational to suppose that our inability to assign the causes of other phenomena arose from our ignorance, than that there were phenomena which were uncaused, and which happened accidentally to be exactly those which we had hitherto had no sufficient opportunity of studying."—Vol. II. p. 108.