Those who have made their way through the German systems of idealism, from Kant to Hegel—destined in a future age to form one of the most curious chapters in the history, or romance, of philosophy—have probably, for the most part, come to the conclusion of their task, with the profound impression of the futility of the study of metaphysics, which, full of labour, is yet fruitless as idleness. L'art de s'Égarer avec methode—such it has been wittily defined, and such our Teutonic neighbours have been resolved to demonstrate it. Yet, this is not altogether the impression, we think, which such a course of study ought to produce: a better lesson may be drawn from it. There is, after all, a right as well as a wrong method of philosophising. The one leads, it may be, but to a few modest results, of no very brilliant or original character, yet of sterling value and importance. The other may conduct to startling paradox, to applauded subtleties, to bold and novel speculations, but baseless, transient, treacherous. It evidently requires something more than intellectual keenness; it requires the virtue of forbearance, and a temperate spirit, to adhere to sober rectitude of thought, and eschew the temptations that a daring and self-willed philosophy displays. Such is the lesson which these "follies of the wise" ought to inculcate. They should lead us to intrench ourselves more securely than ever within the sound rules for the investigation of truth.

Philosophise men will—men must. Even the darkest paths, and the most labyrinthine of metaphysics, must be perpetually trodden. In vain is it proclaimed that they lead back only to the point of ignorance from which they started; in vain is it demonstrated that certain problems are indemonstrable. If the same race of men lived for ever upon the earth, such inextricable problems might at length be set at rest. But each new generation finds them as fresh and attractive as if they had never been touched, never probed and tortured by fruitless examination; to each generation they appear in all the unabated charms of mystery; to each generation must their solution at least be shown to be unattainable. In vain you write over the portal Lasciate ogni speranza! there is always a band of youth newly arrived before the gates, who will rush in.

It is futile, therefore, to think of discarding metaphysics; if a good system is not adopted, its contrary will speedily prevail. "A good physician," says Paul Richter, "saves us—from a bad one—if from nothing else." And a rational method of philosophising has, at all events, the same negative merit. Good sense, cries one, is sufficient for all the purposes of life, and even for all the useful walks of literature. The remark might be pertinent enough if you could secure a man in the quiet, uninterrupted possession of his plain good sense. But he who has not studied philosophy in his youth, will probably plunge into it, without study, in his old age. There is no guarantee against the infection of speculative thought. Some question suddenly interests the man of hitherto quiescent temper—invades his tranquillity—prompts him to penetrate below the surface of the matter—to analyse its intricacies—to sound its depths. Meanwhile, untutored, undisciplined for such labours, he speedily involves himself in inextricable difficulties—grasps at some plausibility that had been a thousand times before seized on and relinquished—tilts valiantly at his men of straw—thrice slays the dead—and in short, strong-limbed as he is, and with all his full-grown thews and sinews, plays upon this new arena all the vagaries of a child. It may be said of philosophy, as it has been said of love,—it is, or it has been, or it will one day be, your master.

We have seen reverend doctors of divinity present no very dignified spectacle when they have suddenly bethought them of paying their somewhat late devotions to philosophy. Accustomed to receive, as their due, a profound respect from others, they assume with easy confidence the cloak of the philosopher; and while they are thinking only how to arrange its folds with classic grace, they are unconsciously winding round their sturdy limbs what will sadly entangle their feet, and bring them, with shame and sore contusions, to the ground. Some will parade an ancient theory of morals, and introduce to us with all the pride of fresh discovery what now looks "as pale and hollow as a ghost." Others explain the beautiful; and with a charming audacity, a courage that is quite exhilarating, propound some theoretic fancy which has the same relation to philosophy that Quarle's Emblems bear to that pictorial art they especially delight to descant upon. But the greater number of these belated wanderers in the paths of philosophy, enter through the portals of religion. How could it be otherwise? Religion and philosophy touch at so many points—have so many problems in common—that the first moment the good man bethinks him he will be profound, sees him plunged in all the darkest enigmas of speculative thought, there to lose himself in we know not what heretical delusions.

Therefore, there is no one thing on which we are more disposed to congratulate Scotland than on her chairs of philosophy. Occupied by her most distinguished men, and teaching a sound system of psychology, they early train her youth to the severest and most useful discipline of thought. They have given its tone and its strength to the intellect of Scotland. They teach it to face all difficulties manfully, and to turn with equal manliness from vain and presumptuous speculations, which, under a boastful show of profundity, conceal invariably an arrant dogmatism. We turn with hearty satisfaction from the tissue of false subtleties which the German professor lays before his youth, to the careful and modest analysis of mental phenomena by which a professor in our northern universities at once enlightens and fortifies the mind. Scotland, may well be proud of the position she has now long held in the philosophical world. Her oscillations of error she, too, has no doubt exhibited—a necessary condition this of vitality and progress—but nowhere has a body of philosophers so systematically adhered to the sound canons of reasoning and research, and that upon a subject where there is the greatest facility and temptation to depart from them.

M. Cousin, and others who take that discursive light-tripping philosopher for their guide, have represented the Scotch as a sort of half Germans, and have both praised them, and praised them coldly, on this very account, that they have travelled half-way, and only half-way, towards the region of "high a priori" speculation. With M. Cousin's permission, the Scotch come of quite another house. His praise we should beg leave to decline: he may carry it to Alexandria, if he will. The method of philosophising pursued in Germany is fundamentally different from that which happily obtains in Scotland. No two schools of philosophy could resemble each other less. For ourselves, we regard the whole history of modern German speculation—the most remarkable instance, in our judgment, of great mental powers ill applied which the world has ever witnessed—as one continuous comment upon this text, the necessity of adhering to careful, honest observation of mental phenomena, however homely may be the results of such observation, and the astounding conclusions to which a train of thought rigidly pursued may conduct us, if, at its very point of departure, it has broken loose from this the first obligation of philosophy. The whole career of German speculation manifests a disregard of some of those fundamental principles of human belief, which, according to M. Cousin himself, it is the peculiar merit of the Scotch to have seized and held with tenacity.

These observations we will illustrate by a glance at the theories propounded on the great subject of perception—on the nature of our knowledge of the external world, this visible and tangible creation.

To a plain unsophisticated man, a stranger to the subtleties of metaphysical thought, it appears quite inconceivable, when he is told that the existence of the visible and palpable scene before him should be converted into a problem of apparently invincible difficulty. Yet so it is. The metaphysician first carries off in triumph what are called its secondary qualities, as colour and heat, proving them to be no qualities of matter, but of mind, or the sensitive being. He next assails what had been pronounced to be its primary or essential qualities; the dark tangible mass that he had left behind is not suffered to retain its inert existence; extension, the power to fill space or resist pressure, what are these, he asks, but our own sensations or remembered sensations of touch, which have got associated, embodied together, agglomerated round some occult cause? What, after all, he exclaims, do we know of matter but as a something which possesses certain influences over us?—a something which is utterly unrepresented to us by the senses. And now this word "substance," which formerly expressed a thing so well known, and every moment handled and looked at, is transformed to an invisible, intangible, imperceptible substratum—an unknown upholder of certain qualities, or, in more exact language, an unseen power clothing itself in our attributes—an existence far more resembling what is popularly understood by spirit than by matter. At length, even this unseen substratum is drawn within the world of thought, and becomes itself mere thought. There is no matter, there is no space, save what the mind creates for, and out of itself. Our man of simple apprehension, much bewildered, not at all convinced, breaks from the chain of sophistry, opens wide his eyes, and declares after all that "seeing is believing."

We think so too.

On this subject of perception it is well known that Reid and Stewart, refusing to be drawn into any hypothesis or unsatisfactory analysis, contented themselves with stating, in the preciser language of the schools, the fact as it appears to the plain unsophisticated observer. Reid's explanations are unfortunately mingled up with his controversy against the old hypothesis of ideas or images of things perceived in the mind—an hypothesis combated by him with unnecessary vehemence—but this detracts little from their substantive correctness or utility. This strange notion of images emanating from the external object, entering the mind, and being there perceived, was, after all, in its origin, rather a physical than a metaphysical hypothesis. The ancient speculator upon the causes of things felt, as we feel at this moment, the necessity for some medium of communication between the eye and the distant object, and not having detected this medium in the light which traverses or fills the space between them, he had recourse to this clumsy invention of images or species raying out from the surfaces of things. At the time when Reid wrote, this hypothesis, in its crude form, cannot be said to have existed; but it had left its traces in the philosophical language of the period, and there was certainly a vague notion prevalent that the idea of an object was a tertium quid, a something that was neither the mind nor the object.

We will quote the statement which Dugald Stewart makes of Reid's doctrine of perception. As he himself adopts the statement, it will embrace at once the opinion of both these philosophers:—

"To what, may it be asked, does this statement (of Reid's) amount? Merely to this, that the mind is so formed that certain impressions produced on our organs of sense by external objects, are followed by correspondent sensations, and that these sensations (which have no more resemblance to the qualities of matter, than the words of a language have to the things they denote) are followed by a perception of the existence and qualities of the bodies by which the impressions are made; that all the steps of this progress are equally incomprehensible; and that for any thing we can prove to the contrary, the connexion between the sensation and the perception, as well as that between the impression and the sensation, may be both arbitrary; that it is therefore by no means impossible that our sensations may be merely the occasions on which the correspondent perceptions are excited; and that at any rate the consideration of these sensations, which are attributes of mind, can throw no light on the manner in which we acquire our knowledge of the existence and qualities of body. From this view of the subject, it follows that it is the external objects themselves, and not any species or images of these objects (or, we may add, any mere agglomeration of present and remembered sensations) that the mind perceives; and that although, by the constitution of our nature, certain sensations are rendered the constant antecedents of our perceptions, yet it is just as difficult to explain how our perceptions are obtained by their means, as it would be upon the supposition that the mind were all at once inspired with them, without any concomitant sensations whatever."—(Elements of the Philosophy of the Human Mind, Vol. i. p. 92.)

It is seen here that both Reid and Stewart considered perception as a simple elementary fact or phenomenon of the human mind, and refused their assent to that analysis which would resolve it into sensation, accompanied with certain acts of memory and judgment. This last, however, has been the most popular amongst modern psychologists, who have many of them expressed an extreme impatience at the apparent sluggishness of these veterans in philosophy. We remember the time when we shared the same feeling of impatience, and thought it a most useless encumbrance to maintain this perception amongst the simple elements of the human mind: we now think otherwise, and see reason to acquiesce in the sound judgment, which took up the only safe, though unostentatious position, which this embarrassing subject affords.

Dr Brown, it is well known, departed from his predecessors at this point, and may here be considered as one of the ablest representatives of the sensational school. He expended much ingenuity in his analysis of perception, though in our opinion with very little result. No one saw more distinctly than he, that sensation alone could never give us the idea of an external object, or of space, or any thing external to the mind. No one has more satisfactorily shown that the notion of an extended resisting body, supposed by many to be resolved into the sensations of touch, cannot be derived from this source alone, but must have some other origin than the pure sensation, which is a mere mental phenomenon or state of the consciousness. But he imagined he had overcome the difficulty by introducing to us a new sensation, the muscular, that which we experience when we move our limbs. What he could not derive from the old sense of touch, he thought himself able to deduce from the reasonings of the mind on this muscular sensation; but the same difficulties which he himself so lucidly set forth when treating upon touch, will be found to pursue him here also. This muscular sensation, like every other, is in itself a mere state of the consciousness, begins and ends in a mere pleasure or pain. That it terminates abruptly, and contrary to our volition, in a feeling of resistance, (as when our arm is arrested in its motion,) is saying nothing more than that one sensation gives place to another without our willing it; a statement which might be made in a thousand other cases of sensation with equal propriety. But the author shall explain his own theory.

"The infant stretches his arm for the first time, by that volition without a known object, which is either a mere instinct or very near akin to one; this motion is accompanied with a certain feeling; he repeats the volition, which moves his arm, fifty or one thousand times, and the same progress of feeling takes place during the muscular action. In this repeated progress he feels the truth of that intuitive proposition, which in the whole course of the life that awaits him is to be the source of all his expectations, and the guide of all his actions—the simple proposition that what has been as an antecedent, will be followed by what has been as a consequent. At length he stretches out his arm again, and instead of the accustomed progression, there arises, in the resistance of some object opposed to him, a feeling of a very different kind, which, if he persevere in his voluntary effort, increases gradually to severe pain, before he has half completed the usual progress. There is a difference, therefore, which we may without any absurdity suppose to astonish the little reasoner; for the expectation of similar consequents from similar antecedents, is observable even in his earliest actions, and is probably the result of an original law of mind, as universal as that which renders certain sensations of sight and sound the immediate result of certain affections of our eye or ear. To any being who is thus impressed with belief of similarities of sequence, a different consequent necessarily implies a difference of the antecedent. In the case at present supposed, however, the infant, who as yet knows nothing but himself, is conscious of no previous difference; and the feeling of resistance seems to him, therefore, something unknown, which has its cause in something that is not himself."—(Vol. i. p. 514.)

There is a certain pre-arrangement here of the circumstances to suit the convenience of explanation. The little arm of the infant being very closely fastened to its own little body, it could hardly move it fifty or a thousand times in succession, or even once, without its muscular sensation terminating in the sense of resistance, or pressure, which is but another form of the sense of touch. In short, this would be always sooner or later the consequent upon this muscular sensation. And it appears very evident that "the little reasoner," more especially if he held the same doctrine as Brown on the nature of cause and effect, would look no further than the first sensation for the cause of the second. There would be few instances in his limited experience more marked of invariable antecedence and consequence than this,—that the muscular sensation would sooner or later be followed by a tactual one. If we could suppose it possible, that the infant logician had to make the discovery of an external world by an effort of reasoning upon its sensations, we should say that this case was the least likely of any to lead him to the discovery—the least likely to impel him to look out of the circle of sensations for a cause of them.

Mere sensation of any kind, reason on it how we will, cannot account for the perception of external objects, which is another and separate fact. We are reduced to admit that it is by a simple primary law of our constitution that the organs of sense (which may with equal propriety be called the organs of perception) convey to us a knowledge of the external world. We touch, and a tangible extended body is made known to us; we open our eyes, and a visible body is before us.

Dr Brown, adopting and refining upon Berkeley's theory of vision, attributes originally nothing more than the mere sensation of colour to the eye, which sensation, by association with that of touch, becomes extended, so to speak, over an external surface, and defined into limited figures. We are not disposed to lay any greater stress than Dr Brown himself upon the image said to be traced upon the retina; but we say that the eye, as well as the touch, immediately informs us of external surface and definite figure.

There is, it is true, a sensation of colour apart from the perception. This may be separated, in our reflection, from all external surface. It is a pleasure which colour gives, and which enters largely into the complex sentiments of beauty. But our notion of colour itself we cannot dissociate from external surface: we cannot think of colour but as something outward. And if it comes to us originally under the condition of external surface, it must also present itself originally under certain forms and figures; for only where the whole field of vision is occupied by one unvaried colour, as when the eye is fixed upon a cloudless sky, could there be the perception of surface without some figure, more or less defined on it.

And why is it, that on a subject of this nature the manifest facts witnessed in the whole animal creation are to be overlooked? If other animals evidently, on the first opening of their eyes, see form, and movement, and the whole world before them; does not this sufficiently intimate the instantaneous knowledge which it is the nature of vision to bestow? The human infant arrives, indeed, more slowly at the perfect use of its senses. It arrives, also, more slowly at the perfect use of its limbs. But we never conclude because it does not rise and skip about the fields like a dropped lamb, that there is any essential difference between its muscular powers and those of other animals of creation. Why should we suppose that its vision is regulated by different laws merely because it obtains the perfect use of its eyesight somewhat later?

Let us now turn from the imperfect analysis which the sensational school presents, to the speculations of the idealist. It will be seen that the hasty conclusions of the first gave a sort of basis for the strange results to which the second would conduct us.

Kant looked in vain for the idea of extension, or of space, where the philosophers had been seeking it, in the phenomena of sensation. He pronounced, therefore, that it was not derivable from experience, did not come to us from without, through any direct communication from the senses. Not finding this idea of space where the analytical psychologist had been searching for it, he drew it at once from the mind itself. He described it as a product of the subject man, a form of the sensibility with which he invests his own sensations.

We must first remark, that to this description of what perception really is, there lies the same objection that may be urged against the account of the sensationalist. A sensation clothed in space!—is this intelligible? is it by any means an account of the matter? To invest sensation with space, is it not as if we spoke of a pleasure that was square, or of a circular pain?

So far, however, as this internal origin of the idea of space is concerned, the statement of Kant, though expressed in unusual terms, is not opposed to the general belief of mankind, or to our irresistible convictions. It may merely convey this meaning, that the mind has an immediate knowledge (drawn from the laws of its own cogitation) of space, or extension. But then, according to the universal and unalterable convictions of mankind, this idea of space, though it may be derived from the innate resources of the mind, is in fact the knowledge of an external reality—of an objective truth. Kant decided otherwise. He pronounced this form of the sensibility to be merely and only a mode of thought—that space had, in fact, no other existence, was solely a subjective truth.

This one decision has been the cause of, or at least has served as the starting-point for a series of the wildest speculations that perhaps philosophy has to record. And this decision, how arbitrary!—how dogmatic!

It must be manifest, we think, to every intelligent person, that, granting we cannot demonstrate the objective truth of the existence of space, it is equally impossible to prove its subjective nature. We cannot conceive of space but as existing really around us. The metaphysician says we may be deceived. This universal and irresistible conviction—this fundamental law of human belief, may not be correspondent with absolute truth, may not be trustworthy. Granted that we may be deceived, that there is footing here for his scepticism, he cannot proceed a step further, and show that we are deceived. When, in his turn, he would assert, or dogmatise, he at all events is as open to our scepticism as we were to his. If a fundamental belief of this kind is not to be trusted, so neither can it be convicted of falsehood. We cannot launch ourselves out of our own nature; we cannot test our own faculties of cognition. This could only be done by some superior intelligence who could survey apart the object and the percipient subject.

We may be deceived in believing that we ourselves exist—that there is any permanent being we call ourselves—but there is no demonstrating that we are so deceived. The two cases are strictly analogous. We have just the same proof of the existence of the external object as of the thinking and percipient subject. The very first sensation or perception we experience brings with it instantaneously the two correlates, object and subject; they are made known in the same act or feeling; they are made known the one by means of the other—for unless through the means of the antagonist idea of object we should not have that of subject, nor vice versÂ. In our judgment, therefore, there is as little philosophy in denying the external existence of matter as the internal existence of mind. The two ideas, as we have said, rise instantaneously, synchronously, and are in such manner correlates that it is only by the presence of the one that the other reveals itself.[6]

When Kant advanced from doubting of the objective truth of our knowledge of space, to deciding against it—to asserting that it was purely subjective—he was exceeding the limits of the human faculties, and offering a mere dogmatism which can never be brought to any test whatever. He was asking us to judge of the trustworthiness of our faculties of cognition—by what?—by our faculties of cognition. He was elevating what is at best a strange suspicion, a mere guess, into a doctrine.

And the whole superstructure of the systems of idealism which his German followers have reared, rests upon this guess!

Kant left nothing of the material world but an indescribable noumenon, which did not even exist in space. Of course the categories of Aristotle, classifying as they did those relations which constitute our knowledge of this world, were converted by him into mere forms of the understanding, moulding the given products of the sensibility. Certain other regulative modes of thought predominating, in their turn, over the products of the understanding, he called ideas of the pure reason.

His successor, Fichte, it will be seen, advanced but little further when he pronounced for a system of idealism. The subjective nature of our knowledge had been laid down; there was nothing left of the real world but this noumenon which had been ejected from the realm of space; he acted, therefore, a consistent and charitable part, in taking this forlorn and banished entity into the region, at least, of thought. All the external world is now but a projection from the individual mind—the non-ego is but another development of the ego—the object is nothing but a sort of limitation or contrast which the subject throws out, to make a life for itself; the web it spins in the blank infinitude. Of the whole material world we have for ever got rid.

Here it might be supposed that speculation in this direction had reached its extreme point; and as idealism is a system in which the mind cannot long rest, contradicting, as it does, its ineradicable convictions, that here would commence a philosophical revolution, and a return to a more sober and accurate method of investigation. But the German mind has put forth at this point an astonishing fertility. It has played with this idealism, refined upon it, varied it, produced new phases of it; reviving the strangest paradoxes of the Alexandrian school; and teaching—in this, the nineteenth century—with the gravest confidence in the world—with all the assurance of an ancient Scald chanting forth his mythological fables, a whole system of idealistic cosmogony!

Schelling, in his idealism, in some measure reinstated the object; not by reviving the vulgar notion of its reality, but declaring it to be in its essence identical with the subject, and pronouncing both to have an equally real or equally ideal existence. He thus got rid of the embarrassment which encounters us in the ordinary systems of idealism, of the subjective Ego producing the objective Ego. Thought and thing are identical. But this identity is to be recognised only in the mind of God, in the absolute—which develops what in itself is unity in the form of a duality. As if (to use a rude illustration) the same image should be shot from the interior of a magic lantern through two diverging tubes, making that twofold which was itself identical.

As it is hard for common apprehension to conceive this absolute, and seize upon this identity of thought and thing, Schelling invented a faculty of mind expressly for the comprehension of such profound doctrines of philosophy. He called it intellectual intuition. Those who possess it not—and it is by no means general—must be content to live without philosophy. Nor can those on whom nature has failed to bestow this intellectual intuition, acquire it by any study or industry of their own. Philosophus nascitur, non fit.

Viewed from one aspect, Schelling's philosophy is not without a certain charm. "Spirit is invisible nature, nature is visible spirit." In this view of things, if mind loses its pre-eminence, nature, or the visible world, is exalted and spiritualised. It is a system likely to fascinate the poet and the artist, and we believe it has had a recognised influence on the cultivation of the fine arts in Germany. It awakens our enthusiasm for nature. More than ever is mind, is deity, seen in the visible world. Nature is, in fact, deified, whatever other sacrifices are made.

But if there was something for enthusiasm to lay hold of in the system of Schelling, there was much wanting, it seems, to satisfy the rigid demands of philosophy. His cosmogony, his manner of tracing, a priori, the development of all things from the absolute, was considered, by those who understand such profundities, to be deficient in accuracy. Hegel next trod

And we are told gravely, by grave expositors, how, beginning with nothing, he showed, with logical precision, how every thing had regularly proceeded from it!

In the system of Hegel, object and subject are both lost sight of: nothing exists but the relation between them. As the thing and the thought of it are identical, and as the essence of a thought is the relation between two terms, it follows very logically that this relation is all, and that nothing really exists but relations. We should have supposed this to be a fair reductio ad absurdum, proving (if the matter could need of proof) that the thing and the thought were not identical. But the march of ideal philosophy was not to be so easily arrested.

We have now reached what is distinguished as absolute idealism.

"They (the three idealisms) may be thus illustrated," (writes Mr Lewes in his History of Philosophy.) "I see a tree. Fichte tells me that it is I alone who exist; the tree is a modification of my mind. This is subjective idealism. Schelling tells me that both the tree and my ego are existences equally real, or ideal, but they are nothing less than manifestations of the absolute. This is objective idealism. But Hegel tells me, that all these explanations are false. The only thing really existing is the idea—the relation. The ego and the tree are but two terms of the relation, and owe their reality to it. This is absolute idealism."[7]

If Martinus Scriblerus were alive, he also might be tempted to give an illustration of these three forms of idealism.

The crowd of spectators at a fair, he might say, if they see a man dancing upon the tight-rope, strained between two posts—have no doubt in the world that the rope, and the man on it, are equally supported by the same two posts, which, moreover, they presume to stand up there in veritable substantiality before them. Were our three sages at the fair, they would reason otherwise. Fichte would say—these people think there are two posts! There is but one. That left-hand post is but the shadow of the other. It is the right-hand subjective post which has projected it forth.

Schelling, gravely looking on, observes they are both shadows: nay, they are identical. If you were to stand in the centre of the rope, in the point of indifference between them, and to turn round till the intellectual intuition were sufficiently excited, you would find the right-hand and the left-hand post blended together—undistinguishable—you would perceive their absolute identity.

Shadows! identical! Very true, says Hegel, slowly stepping forward, but what a mistake have both philosophers and the vulgar been making all this time! They have presumed that these posts support the rope! It is the rope which upholds the posts; which are indeed but its opposite ends. You may see that, separately, each post is good for nothing; it is the relation between them that is every thing; the rope is all. This alone can be said to exist. Every thing about us is plainly at one end or the other end of this, or some other rope. There runs, he would add, a vulgar tradition that man made the rope. I will demonstrate that the rope made the man and every thing else in the whole fair.

But it is not our object at present to enter further into the labyrinth of German metaphysics; at a future time, if our readers should endure the subject, we will endeavour to act as guide and interpreter through some of its more curious passages; we are here concerned only with the points of view taken of the material world. Have we not said enough to support our thesis? to prove what strange results may be arrived at if philosopher, following after philosopher, bases his speculations on what is current in the school-room, instead of recurring to honest and simple-minded observations of nature—and to show that on this subject of perception our veterans Reid and Stewart have taken up the only safe position our present knowledge admits of?