If these observations be well-founded, they establish three very important facts in the History of the Human Mind. 1. That the notion of the mathematical affections of matter presupposes the exercise of our external senses; inasmuch as it is suggested to us by the same sensations which convey the knowledge of its primary qualities. 2. That this notion involves an irresistible conviction, on our part, not only of the external existence of its objects, but of their necessary and eternal existence; whereas, in the case of the primary qualities of matter, our perceptions are only accompanied with a belief, that these qualities exist externally, and independently of our existence as percipient beings; the supposition of their annihilation by the power of the Creator, implying no absurdity whatsoever. 3. That our conviction of the necessary existence of extension or space, is neither the result of reasoning nor of experience, but is inseparable from the very conception of it; and must therefore be considered as an ultimate and essential law of human thought.

The same conclusion, it is manifest, applies to the notion of time; a notion which, like that of space, presupposes the exercise of our external senses; but which, when it is once acquired, presents irresistibly its object to our thoughts as an existence equally independent of the human mind, and of the material universe. Both these existences, too, swell in the human understanding to infinity,the one to immensity-the other to eternity; nor is it possible for imagination itself to conceive a li

mit to either. How are these facts to be reconciled with that philosophy which teaches that all our knowledge is derived from experience?

The foregoing reasonings have led us, by a very short, and, I hope, satisfactory process, to the general conclusion which forms the fundamental principle of the Kantian system; a system plainly suggested to the author, by the impossibility he found of tracing any resemblance between extension and the sensations of which we are conscious. "The "notion (or intuition) of space," he tells us, "as "well as that of time, is not empirical; that is, it "has not its origin in experience. On the con

trary, both these notions are supposed, or implied, "as conditions in all our empirical perceptions; in"asmuch as we cannot perceive nor conceive an "external object, without representing it to our

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thoughts as in space; nor can we conceive any. "thing, either without us or within us, without re"presenting it to ourselves as in time. Space and "time, therefore, are called, by Kant, the two forms

of our sensibility. The first is the general form "of our external senses; the second the general "form of all our senses, external and internal.

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"These notions of space and of time, however, "although they exist in us à priori, are not, cording to Kant, "innate ideas. If they are an"terior to the perceptions of our senses, it is only "in the order of reason, and not in the order "of time. They have, indeed, their origin in our"selves; but they present themselves to the understanding only in consequence of occasions furnish

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❝ed by our sensations; or (in Kant's language) by "our sensible modifications. Separated from these " modifications, they could not exist; and, without "them, they would have remained for ever latent "and sterile." *

is

* De Gerando, Hist. des Systêmes, Tom. II. p. 208, 209. It proper for me to observe here, that, for the little I know of Kant's philosophy, I am chiefly indebted to his critics and commentators; more particularly to M. De Gerando, who is allowed, even by Kant's countrymen, to have given a faithful exposi tion of his doctrines; and to the author of a book published at Copenhagen, in 1796, entitled, Philosophia Critica secundum Kantium Expositio Systematica. Some very valuable strictures on the general spirit of his system may be collected from the appendix subjoined by M. Prevost to his French translation of Mr Smith's posthumous Essays; from different passages of the Essais Philosophiques of the same author; and from the first article in the second number of the Edinburgh Review.

As to Kant's own works, I must acknowledge, that, although I have frequently attempted to read them in the Latin edition printed at Leipsic, I have always been forced to abandon the undertaking in despair; partly from the scholastic barbarism of the style, and partly from my utter inability to unriddle the author's meaning. Wherever I have happened to obtain a momentary glimpse of light, I have derived it, not from Kant himself, but from my previous acquaintance with those opinions of Leibnitz, Berke ley, Hume, Reid, and others, which he has endeavoured to appropriate to himself under the deep disguise of his new phraseology. No writer certainly ever exemplified more systematically, or more successfully, the precept which Quinctilian (upon the authority of Livy) ascribes to an ancient rhetorician; and which, if the object of the teacher was merely to instruct his pupils how to command the admiration of the multitude, must be allowed to reflect no small honour on his knowledge of human nature. "Neque id novum vitium est, cum jam apud Titum Livium in"veniam fuisse præceptorem aliquem, qui discipulos obscurare

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The only important proposition which I am able to extract from this jargon is, that, as extension and duration cannot be supposed to bear the most distant resemblance to any sensations of which the mind is conscious, the origin of these notions forms a manifest exception to the account given by Locke of the primary sources of our knowledge. This is cisely the ground on which Reid has made his stand against the scheme of Idealism: and I leave it to my readers to judge, whether it was not more philosophical to state, as he has done, the fact, in simple and perspicuous terms, as a demonstration of the imperfection of Locke's theory, than to have reared upon it a superstructure of technical mystery, similar to what is exhibited in the system of the German metaphysician.

In justice, at the same time, to Kant's merits, I must repeat, that Dr Reid would have improved greatly the statement of his argument against Berkeley, if he had kept as constantly in the view of his readers, as Kant has done, the essential distinction which I have endeavoured to point out between the mathematical affections of matter, and its primary

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quæ dicerent, juberent, Græco verbo utens OxÓTICOV. Unde illa scilicet egregia laudatio: Tanto melior, ne ego quidem intel“lexi.”—Quinct. Instit.

En ecrivant, j'ai toujours taché de m'entendre, is an expression which Fontenelle sometimes uses, in speaking of his own literary habits. It conveys a hint not unworthy of the attention of authors; but which I would not venture to recommend to that class who may aspire to the glory of founding new schools of philosophy.

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qualities. Of this distinction he appears to have been fully aware himself, from a passage which I formerly quoted; but he has, in general, slurred it over in a manner which seemed to imply, that he considered them both as precisely of the same kind.

I shall only add farther, that the idea or conception of motion involves the idea both of extension and of time. That the idea of time might have been formed, without any ideas either of extension or of motion, is sufficiently obvious; but it is by no means equally clear, whether the idea of motion presupposes that of extension, or that of extension the idea of motion. The question relates to a fact of some curiosity in the Natural History of the Mind; having, for its object, to ascertain, with logical precision, the occasion on which the idea of extension is, in the first instance, acquired. But it is a question altogether foreign to the subject of the foregoing discussion. Whichever of the two conclusions we may adopt, the force of Reid's argument against Locke's principle will be found to remain undiminished. *

* See note (M.)