tions of touch as I have of pain. When I do so, and compare them together, it appears to me clear as daylight, that the former are not of kin to the latter, nor resemble them in any one feature. They are as unlike, yea as certainly and manifestly unlike, as pain is to the point of a sword. It may be true, that those sensations first introduced the material world to our acquaintance; it may be true. that it seldom or never appears without their company; but, for all that, they are as unlike as the passion of anger is to those features of the countenance which attend it. So that, in the sentence those philosophers have passed against the material world, there is an error persona. Their proof touches not matter, or any of its qualities; but strikes directly against an idol of their own imagination, a material world made of ideas and sensations, which never had, nor can have an existence. Secondly, The very existence of our conceptions of extension, figure, and motion, since they are neither ideas of sensation nor reflection, overturns the whole ideal system, by which the material world hath been tried and condemned;* so that there hath been likewise in this sentence an error juris. It is a very fine and a just observation of Locke, that, as no human art can create a single particle of matter, and the whole extent of our power over the material world consists in compounding, combining, and disjoining the matter made to our hands; so, in the world of thought, the materials are all made by nature, and can only be variously combined and disjoined by us. So that it is impossible for reason or prejudice, true or false philosophy, to produce one simple notion or conception, which is not the work of nature, and the result of our constitution. The conception of extension, motion, and the other attributes of matter, cannot be the effect of error or prejudice; it must be the work of nature. And the power or faculty by which we acquire those conceptions, must be something different from any power of the human mind that hath been explained, since it is neither sensation nor reflection. This I would, therefore, humbly propose, as an experimentum crucis, by which the ideal system must stand or fall; and it brings the matter to a short issue: Extension, figure, motion, may, any one, or all of them, be taken for the subject of this experiment. Either they are ideas of sens It only overturns that Idealism founded on the clumsy hypothesis of ideas being something different, both from the reality they represent, and from the mind contemplating their representation, and which, also, derives all such ideas from without. This doc. trine may subvert the Idealism of Berkeley, but it even supplies a basis for ar. Idealism like that of Fichte. See the following note.-H. ation, or they are not. If any one of them can be shewn to be an idea of sensation, or to have the least resemblance to any sensation, I lay my hand upon my mouth, and give up all pretence to reconcile reason to common sense in this matter, and must suffer the ideal scepticism to triumph. But if, on the other hand, they are not ideas of sensation, nor like to any sensation, then the ideal system is a rope of sand, and all the laboured arguments of the sceptical philosophy against a material world, and against the existence of every thing but impressions and ideas, proceed upon a false hypothesis." Nothing is easier than to shew, that, so far from refuting Idealism, this doctrine affords it the best of all possible foundations. If idealism, indeed, supposed the existence of ideas as tertia quædam, distinct at once from the material object and the immaterial subject, these intermediate entities being likewise held to originate immediately or mediately in senseif this hypothesis, I say, were requisite to Idealism, then would Reid's criticism of that doctrine be a com. plete and final confutation. But as this criticism did not contemplate, so it does not confute that sim. pler and more refined Idealism, which views.in ideas only modifications of the mind itself; and which, in place of sensualizing intellect, intellectualizes sense. On the contrary, Reid, (and herein he is followed by Mr Stewart,) in the doctrine now maintained, asserts the very positions on which this scheme of Idealism establishes its conclusions. An Egoistical Idealism is established, on the doctrine, that all our knowledge is merely subjective, or of the mind itself; that the Ego has no immediate cognizance of a Non-Ego as existing, but that the Non-Ego is only represented to us in a modification of the self-conscious Ego. This doctrine being admitted, the Idealist has only to shew that the supposition of a Non-Ego, or external world really existent, is a groundless and unnecessary assumption; for, while the law of parcimony prohibits the multiplication of substances or causes beyond what the phænomena require, we have manifestly no right to postulate for the Non. Eg the dignity of an independent substance beyond the Figo, seeing that this Non- go is, ez hypothesi, known to us, consequently exists for us, only as a phænomenon of the Ego-Now, the doctrine of our Scottish philo. sophers is, in fact, the very groundwork on which the Egoistical Idealism reposes. That doctrine not only maintains our sensations of the secondary qua. lities to be the mere effects of certain unknown causes, of which we are consequently entitled to affirm nothing, but that we have no direct and imme diate perception of extension and the other primary qualities of matter. To limit ourselves to extension, (or space,) which figure and motion (the two other qualities proposed by Reid for the experiment) sup. pose, it is evident that if extension be not immediately perceived as externally existing, extended objects cannot be immediately perceived as realities out, and independent, of the percipient subject; for, if we were capable of such a perception of such objects, we should necessarily be also capable of a perception of this, the one essential attribute of their existence. But, on the doctrine of our Scottish philosophers, Extension is a notion suggested on occasion of sens. ations supposed to be determined by certain unknown causes; which unknown causes are again supposed to be existences independent of the mind, and extended their complement, in fact, constituting the external world. All our knowledge of the Non-Ego is thus merely ideal and mediate; we have no knowledge of any really objective reality, except through a subjective representation or notion; in other words. we are only immediat ly cognizant of certain modes of our own minds, and, in and through them, mediately warned of the phænomena of the material universe. In all essential respects, this doc. trine of Reid and Stewart is identical with Kant's; except that the German philosopher, in holding space If our philosophy concerning the mind be so lame with regard to the origin of our notions of the clearest, most simple, and most familiar objects of thought, and the powers from which they are derived, can we expect that it should be more perfect in the account it gives of the origin of our opinions and belief? We have seen already some instances of its imperfection in this respect and, perhaps, that same nature which hath given us the power to conceive things altogether unlike to any of our sensations, or to any operation of our minds, hath likewise provided for our belief of them, by some part of our constitution hitherto not explained. : Bishop Berkeley hath proved, beyond the possibility of reply, that we cannot by reasoning infer the existence of matter from our sensations; and the author of the "Treatise of Human Nature" hath proved no less clearly, that we cannot by reasoning infer the existence of our own or other minds from our sensations. But are we to admit nothing but what can be proved by reasoning? Then we must be sceptics indeed, and believe nothing at all. The author of the "Treatise of Human Nature" appears to me to be but a half-sceptic. He hath not followed his principles so far as they lead him; but, after having, with unparalleled intrepidity and success, combated vulgar prejudices, when he had but one blow to strike, his courage fails him, he fairly lays down his arms, and yields himself a captive to the most common of all vulgar prejudices-I mean the belief of the existence of his own impressions and ideas.* to be a necessary form of our conceptions of external things, prudently declined a-serting that these unknown things are, in themselves, extended. Now, the doctrine of Kant has been rigorously proved by Jacobi and Fichie to be, in its legitimate issue, a doctrine of absolute Idealism; and the demonstrations which the philosopher of Koenigsberg has given of the existence of an external world, have been long admitted, even by his disciples them elves, to be inconclusive. But our Scottish philosophers appeal to an argument which the German philoso pher overtly rejected-the argument, as it is called, from common sense. In their hands however, this argument is unavailing; for, if it be good against the conclusions of the Idealist, it is good against the premises which they afford him. The common sense of mankind only assures us of the existence of an external and extended world, in assuring us that we are conscious, not merely of the phænomena of mind in relation to matter, but of the phænomena of matter in relation to mind-in other words, that we are immediately percipient of extended things. Reid himself seems to have become obscurely aware of this condition; and, though he never retracted his doctrine concerning the mere suggestion of extensin, we find, in his " Essays on the Intellectual Powers," assertions in regard to the immediate perception of external things, which would tend to shew that bis later views were more in unison with the ne. cessary convictions of mankind. But of this again. -H. I beg, therefore, to have the honour of making an addition to the sceptical system, without which I conceive it cannot hang together. I affirm, that the belief of the existence of impressions and ideas, is as little supported by reason, as that of the existence of minds and bodies. No man ever did or could offer any reason for this belief. ness are real, in so far as we are conscious of them. I cannot doubt, for example, that I am actually conscious of a certain feeling of fragrance, and of certain perceptions of colour, figure, &c. when I see rienced, I cannot doubt, because they are facts of and smell a rose. Of the reality of these, as expe- given in consciousness, scepticism is impossible. But In Reid's strictures upon Hume, he confounds two opposite things. He reproaches that philosopher with inconsequence, in holding to" the belief of the existence of his own impressions and ideas." Now, if, by the existence of impressions and ideas, Reid meant their existence as mere phænomena of consciousness, his criticism is inept; for a disbelief of their existence, as such phænomena, would have been a suicidal act in the sceptic. If, again, he meant by impressions and ideas the hypothesis of representative entities different from the mind and its modifications; in that case the objection is equally invalid. Hume was a sceptic; that is, he accep ́ed the premises afforded him by the doginatist, and carried these premises to their legitimate con sequences. To blame Hume, therefore, for not having doubted of his borrowed principles, is to blame the sceptic for not performing a part altogether inconsistent with his vocation. But, in point of fact, the hypothesis of such entities is of no value to the idealist or sceptic. Impressions and ideas, viewed as mental modes, would have answered Hume's purpose not a whit worse than impressions and ideas viewed as objects, but not as affections of mind. The most consistent scheme of idealism known in the history of philosophy is that of Fichte; and Fichte's idealism is founded on a basis which ex. cludes that crude hypothesis of ideas on which alone Reid imagined any doctrine of Idealism could possibly be established. And is the acknowledged result of the Fichtean dogmatism less a nihilism than the scepticism of Hume?" The sum total," says Fichte, "is this:-There is absolutely nothing permanent either without me or within me, but only an unceasing change. I know absolutely nothing of any existence, not even of my own. I myself know nothing, and am nothing. Images (Bilder) there are: they constitute all that apparently exists, and what they know of themselves is after the manner of images; images that pass and vanish without there being aught to witness their transition; that consist in fact of the images of images, without sig. nificance and without an aim. I myself am one of these images; nay, I am not even thus much, but only a confused image of images. All reality is con. verted into a marvellous dream, without a life to dream of, and without a mind to dream; into a dream made up only of a dream of itself. Percep tion is a dream; thought-the source of all the existence and all the reality which I imagine to myself of my existence, of my power, of my destination There is in this and the two following paragraphs a confusion and inaccuracy which it is requisite to notice-There is no scepticism possible touching the facts of consciousness in themselves. We cannot doubt that the phænomena of conscious. is the dream of that dream."-H. K Des Cartes took it for granted, that he principle. The belief of it, and the very thought, and had sensations and ideas; so conception of it, are equally parts of our have all his followers done. Even the hero constitution. If we are deceived in it, we of scepticism hath yielded this point, I crave are deceived by Him that made us, and leave to say, weakly and imprudently. I there is no remedy.* say so, because I am persuaded that there is no principle of his philosophy that obliged him to make this concession. And what is there in impressions and ideas so formidable, that this all-conquering philosophy, after triumphing over every other existence, should pay homage to them? Besides, the concession is dangerous: for belief is of such a nature, that, if you leave any root, it will spread; and you may more easily pull it up altogether, than say, Hitherto shalt thou go and no further: the existence of impressions and ideas I give up to thee; but see thou pretend to nothing more. A thorough and consistent sceptic will never, therefore, yield this point; and while he holds it, you can never oblige him to yield anything else. To such a sceptic I have nothing to say; but of the semi-sceptics, I should beg to know, why they believe the existence of their impressions and ideas. The true reason I take to be, because they cannot help it; and the same reason will lead them to believe many other things. All reasoning must be from first principles; and for first principles no other reason can be given but this, that, by the constitution of our nature, we are under a necessity of assenting to them. Such principles are parts of our constitution, no less than the power of thinking: reason can neither make nor destroy them; nor can it do anything without them: it is like a telescope, which may help a man to see farther, who hath eyes; but, without eyes, a telescope shews nothing at all. A mathematician cannot prove the truth of his axioms, nor can he prove anything, unless he takes them for granted. We cannot prove the existence of our minds, nor even of our thoughts and sensations. A historian, or a witness, can prove nothing, unless it is taken for granted that the memory and senses may be trusted. A natural philosopher can prove nothing, unless it is taken for granted that the course of nature is steady and uniform. How or when I got such first principles, upon which I build all my reasoning, I know not; for I had them before I can remember: but I am sure they are parts of my constitution, and that I cannot throw them off. That our thoughts and sensations must have a subject, which we call ourself, is not therefore an opinion got by reasoning, but a natural principle. That our sensations of touch indicate something external, extended, figured, hard or soft, is not a deduction of reason, but a natural I do not mean to affirm, that the sensations of touch do, from the very first, suggest the same notions of body and its qualities which they do when we are grown up. Perhaps Nature is frugal in this, as in her other operations. The passion of love, with all its concomitant sentiments and desires, is naturally suggested by the perception of beauty in the other sex; yet the same perception does not suggest the tender passion till a certain period of life. A blow given to an infant, raises grief and lamentation; but when he grows up, it as naturally stirs resentment, and prompts him to resistance. Perhaps a child in the womb, or for some short period of its existence, is merely a sentient being; the faculties by which it perceives an external world, by which it reflects on its own thoughts, and existence, and relation to other things, as well as its reasoning and moral faculties, unfold themselves by degrees; so that it is inspired with the various principles of common sense, as with the passions of love and resentment, when it has occasion for them. Section VIII. OF THE SYSTEMS OF PHILOSOPHERS CONCERN ING THE SENSES.† All the systems of philosophers about our senses and their objects have split upon this rock, of not distinguishing properly The philosophers who have most loudly appealed to the veracity of God, and the natural conviction of mankind, in refutation of certain obnoxious conclusions, have too often silently contradicted that vera. city and those convictions, when opposed to certain favourite opinions. But it is evident that such authority is either good for all, or good for nothing. Our natural consciousness assures us (and the fact of that assurance is admitted by philosophers of all opinions) that we have an immediate knowledge of the very things themselves of an external and extended world; and, on the ground of this knowledge alone, is the belief of mankind founded, that such a world really exists. Reid ought, therefore, either to have given up his doctrine of the mere suggestion of extension, &c., as subjective notions, on the occasion of sensation, or not to appeal to the Divine veracity, and the common sense of mankind, in favour of conclusions of which that doctrine subverts the foundation. In this inconsistency, Reid has, however, besides Des Cartes, many distinguished copartners.-H. on. On this subject, see" Essays on the Intellectual Powers," Essay II., chap. 7-15, and the notes thereIt is perhaps proper to recall to the reader's at. tention, that, by the Ideal Theory, Reid always understands the ruder form of the doctrine, which holds that ideas are entities, different both from the external object and from the percipient mind, and that he had no conception of the finer form of that doctrine, which holds that all that we are conscious only a modification of the mind itself-See Note of in perception, (of course also in imagination,) is C.-H. sensations which can have no existence but when they are felt, from the things suggested by them. Aristotle-with as distinguishing a head as ever applied to philosophical disquisitions-confounds these two; and makes every sensation to be the form, without the matter, of the thing perceived by it. As the impression of a seal upon wax has the form of the seal but nothing of the matter of it, so he conceived our sensations to be impressions upon the mind, which bear the image, likeness, or form of the external thing perceived, without the matter of it. Colour, sound, and smell, as well as extension, figure, and hardness, are, according to him, various forms of matter: our sensations are the same forms imprinted on the mind, a d perceived in its own intellect. It is evident from this, that Aristotle made no distinction between primary and secondary qualities of bodies, although that distinction was made by Democritus, Epicurus, and others of the ancients.⚫ Des Cartes, Malebranche, and Locke, revived the distinction between primary and secondary qualities; but they made the secondary qualities mere sensations, and the primary ones resemblances of our sensations. They maintained that colour, sound, and heat, are not anything in bodies, but sensations of the mind; at the same time, they acknowledged some particular texture or modification of the body to be the cause or occasion of those sensations; but to this modification they gave no name. Whereas, by the vulgar, the names of colour, heat, and sound, are but rarely applied to the sensations, and most commonly to those unknown causes of them, as hath been already explained. The constitution of our nature leads us rather to attend to the things signified by the sensation than to the sensation itself, and to give a name to the former rather than to the latter. Thus we see, that, with regard to secondary qualities, these philosophers thought with the vulgar, and with common sense. Their paradoxes were only an abuse of words; for when they maintain, as an important modern discovery, that there is no heat in the fire, they mean no more, than that the fire does not feel heat, which every one knew before. With regard to primary qualities, these philosophers erred more grossly. They indeed believed the existence of those qualities; but they did not at all attend to the sensations that suggest them, which, having no names, have been as little considered as if they had no existence. They were aware that figure, extension, and On this last, see Aristotle. De Anima, L. III, e. 1, and Metaph. L. III. c. 5.-The Aristotelic dis tinction of first and second qualities was of another kind.-H. | hardness, are perceived by means of sensations of touch; whence they rashly concluded, that these sensations must be images and resemblances of figure, extension, and hardness. The received hypothesis of ideas naturally led them to this conclusion: and indeed cannot consist with any other; for, according to that hypothesis, external things must be perceived by means of images of them in the mind; and what can those images of external things in the mind be, but the sensations by which we perceive them? This, however, was to draw a conclusion from a hypothesis against fact. We need not have recourse to any hypothesis to know what our sensations are, or what they are like. By a proper degree of reflection and attention we may understand them perfectly, and be as certain that they are not like any quality of body, as we can be, that the toothache is not like a triangle. How a sensation should instantly make us conceive and believe the existence of an external thing altogether unlike to it, I do not pretend to know; and when I say that the one suggests the other, I mean not to explain the manner of their connection, but to express a fact, which every one may be conscious of-namely, that, by a law of our nature, such a conception and belief constantly and immediately follow the sensation. Bishop Berkeley gave new light to this subject, by shewing, that the qualities of an inanimate thing, such as matter is conceived to be, cannot resemble any sensation; that it is impossible to conceive anything like the sensations of our minds, but the sensations of other minds. Every one that attends properly to his sensations must assent to this; yet it had escaped all the philosophers that came before Berkeley; it had escaped even the ingenious Locke, who had so much practised reflection on the operations of his own mind. So difficult it is to attend properly even to our own feelings. They are so accustomed to pass through the mind unobserved, and instantly to make way for that which nature intended them to signify, that it is extremely difficult to stop, and survey them; and when we think we have acquired this power, perhaps the mind still fluctuates between the sensation and its associated quality, so that they mix together, and present something to the imagination that is compounded of both. Thus, in a globe or cylinder, whose opposite sides are quite unlike in colour, if you turn it slowly, the colours are perfectly distinguishable, and their dissimilitude is manifest; but if it is turned fast, they lose their distinction, and seem to be of one and the same colour. No succession can be more quick than that of tangible qualities to the sensations with which nature has associated them: but when one has once acquired the art of making them separate and distinct objects of thought, he will then clearly perceive that the maxim of Bishop Berkeley, above-mentioned, is self-evident; and that the features of the face are not more unlike to a passion of the mind which they indicate, than the sensations of touch are to the primary qualities of body. But let us observe what use the Bishop makes of this important discovery. Why, he concludes, that we can have no conception of an inanimate substance, such as matter is conceived to be, or of any of its qualities; and that there is the strongest ground to believe that there is no existence in nature but minds, sensations, and ideas: if there is any other kind of existences, it must be what we neither have nor can have any conception of. But how does this follow? Why, thus: We can have no conception of anything but what resembles some sensation or idea in our minds; but the sensations and ideas in our minds can resemble nothing but the sensations and ideas in other minds; therefore, the conclusion is evident. This argument, we see, leans upon two propositions. The last of them the ingenious author hath, indeed, made evident to all that understand his reasoning, and can attend to their own sensations: but the first proposition he never attempts to prove; it is taken from the doctrine of ideas, which hath been so universally received by philosophers, that it was thought to need no proof. We may here again observe, that this acute writer argues from a hypothesis against fact, and against the common sense of mankind. That we can have no conception of anything, unless there is some impression, sensation, or idea, in our minds which resembles it, is indeed an opinion which hath been very generally received among philosophers; but it is neither self-evident, nor hath it been clearly proved; and therefore it hath been more reasonable to call in question this doctrine of philosophers, than to discard the material world, and by that means expose philosophy to the ridicule of all men who will not offer up common sense as a sacrifice to metaphysics. We ought, however, to do this justice both to the Bishop of Cloyne and to the author of the "Treatise of Human Nature," to acknowledge, that their conclusions are justly drawn from the doctrine of ideas, which has been so universally received. On the other hand, from the character of Bishop Berkeley, and of his predecessors, Des Cartes, Locke, and Malebranche, we may venture to say, that, if they had seen all the consequences of this doctrine, as clearly as the author before mentioned did, they would have suspected it vehemently, and examined it more carefully than they appear to have done. The theory of ideas, like the Trojan horse, had a specious appearance both of innocence and beauty; but if those philosophers had known that it carried in its belly death and destruction to all science and common sense, they would not have broken down their walls to give it admittance. That we have clear and distinct conceptions of extension, figure, motion, and other attributes of body, which are neither sensations, nor like any sensation, is a fact of which we may be as certain as that we have sensations. And that all mankind have a fixed belief of an external material world—a belief which is neither got by reasoning nor education, and a belief which we cannot shake off, even when we seem to have strong arguments against it and no shadow of argument for it-is likewise a fact, for which we have all the evidence that the nature of the thing admits. These facts are phænomena of human nature, from which we may justly argue against any hypothesis, however generally received. But to argue from a hypothesis against facts, is contrary to the rules of true philosophy. CHAPTER VI. OF SEEING. Section I. THE EXCELLENCE AND DIGNITY OF THIS FACULTY. THE advances made in the knowledge of optics in the last age and in the present, and chiefly the discoveries of Sir Isaac Newton, do honour, not to philosophy only, but to human nature. Such discoveries ought for ever to put to shame the ignoble attempts of our modern sceptics to depreciate the human understanding, and to dispirit men in the search of truth, by representing the human faculties as fit for nothing but to lead us into absurdities and contradictions. Of the faculties called the five senses, sight is without doubt the noblest. The rays of light, which minister to this sense, and of which, without it, we could never have had the least conception, are the most wonderful and astonishing part of the inanimate creation. We must be satisfied of this, if we consider their extreme minuteness; their inconceivable velocity; |