cise of our free-will, a high prerogative of our nature, is often so incautious as to make us not discern truth from falsehood, and affirm or deny, by a voluntary act, that which we do not distinctly apprehend. The properties of quantity, founded on our ideas of extension and number, are distinctly perceived by our minds, and hence the sciences of arithmetic and geometry are certainly true. But when he turns his thoughts to the phænomena of external sensation, Descartes cannot wholly extricate himself from his original concession, the basis of his doubt, that the senses do sometimes deceive us. He endeavours to reconcile this with his own theory, which had built the certainty of all that we clearly hold certain on the perfect veracity of God. secondary qualities. 92. It is in this inquiry that he reaches that important Primary and distinction between the primary and secondary properties of matter, (the latter being modifications of the former, relative only to our apprehension, but not inherent in things,) which, without being wholly new, contradicted the Aristotelian theories of the schools; and 66 d See Stewart's First Dissertation on the Progress of Philosophy. This writer has justly observed, that many persons conceive colour to be inherent in the object, so that the censure of Reid on Descartes and his followers, as having pretended to discover what no one doubted, is at least unreasonable in this respect. A late writer has gone so far as to say, Nothing at first can seem a more rational, obvious, and incontrovertible conclusion, than that the colour of a body is an inherent quality, like its weight, hardness, &c.; and that to see the object, and to see it of its own colour, when nothing intervenes between our eyes and it, are one and the same thing. Yet this is only a prejudice," &c. Herschel's Discourse on Nat. Philos., p. 82. I almost even suspect that the notion of sounds and smells, being secondary or merely sensible qualities, is not distinct in all men's minds. But after we are become familiar with correct ideas, it is not easy to revive prejudices in our imagination. In the same page of Stewart's Dissertation, he has been led by dislike of the university of Oxford to misconceive, in an extraordinary manner, a passage of Addison in the Guardian, which is evidently a sportive ridicule of the Cartesian theory, and is absolutely inapplicable to the Aristotelian. [The most remarkable circumstance in Reid's animadversion on Descartes, as having announced nothing but what was generally known, is that he had himself, in his Inquiry into the Human Mind, contended very dogmatically in favour of the vulgar notion that secondary qualities exist in bodies, independently of sensation. "This scarlet rose which is before me, is still a scarlet rose when I shut my eyes, and was so at midnight when no eye saw it. The colour remains when the appearance ceases; it remains the same when the appearance changes." Chap. vi. § 4. He even uses similar language as to perfumes, which, indeed, stand on the same ground, though we feel less of the prejudice in favour of their reality than of that of colours. Nothing can be more obvious than the reply: the colour remains only on the tacit hypothesis that some one is looking at the object; at midnight we can hardly say that the rose is red, except by an additional hypothesis, that the day should break. "We never," he proceeds, “as far as I can judge, give the name of colour to the sensation, but to the quality only." How then do we talk of bright, he remarked that we are never, strictly speaking, deceived by our senses, but by the inferences which we draw from them. 93. Such is nearly the substance, exclusive of a great variety of more or less episodical theories, of the three metaphysical works of Descartes, the history of the soul's progress from opinion to doubt, and from doubt to certainty. Few would dispute, at the present day, that he has destroyed too much of his foundations to render his superstructure stable; and to readers averse from metaphysical reflection, he must seem little else than an idle theorist, weaving cobwebs for pastime which common sense sweeps away. It is fair, however, to observe, that no one was more careful than Descartes to guard against any practical scepticism in the affairs of life. He even goes so far as to maintain, that a man having adopted any practical opinion on such grounds as seem probable, should pursue it with as much steadiness as if it were founded on demonstration; observing, however, as a general rule, to choose the most moderate opinions among those which he should find current in his own country. made to his 94. The objections adduced against the Meditations are in a series of seven. The first are by a theologian Objections named Caterus, the second by Mersenne, the third Meditations. by Hobbes, the fourth by Arnauld, the fifth by Gassendi, the sixth by some anonymous writers, the seventh by a Jesuit of the name of Bourdin. To all of these Descartes replied with spirit and acuteness. By far the most important controversy was with Gassendi, whose objections were stated more briefly, and, I think, with less skill, by Hobbes. It was the first trumpet in the new philosophy of an ancient war between the sensual and ideal schools of psychology. Descartes had revived, and placed in a clearer light, the doctrine of mind, as not absolutely de dull, glaring, gay, dazzling colours? Do not these words refer to a sensation, rather than to a configuration of parts in the coloured body by which it reflects or refracts light? But this first production of Reid, though abounding with acute and original remarks, is too much disfigured by a tendency to halloo on the multitude against speculative philosophy. The appeal to common sense, that is, the crude notions of men who had never reflected, even enough to use language with precision, would have been fatal to psychology. Reid afterwards laid aside the popular tone in writing on philosophy, though, perhaps, he was always too much inclined to cut knots when he could not untie them.— 1847.] e Vol. i. p. 147. Vol. iii. p. 64. pendent upon the senses, nor of the same nature as their objects. Stewart does not acknowledge him as the first teacher of the soul's immateriality. "That many of the schoolmen, and that the wisest of the ancient philosophers, when they described the mind as a spirit, or as a spark of celestial fire, employed these expressions, not with any intention to materialise its essence, but merely from want of more unexceptionable language, might be shown with demonstrative evidence, if this were the proper place for entering into the discussion." But though it cannot be said that Descartes was absolutely the first who maintained the strict immateriality of the soul, it is manifest to any one who has read his correspondence, that the tenet, instead of being general, as we are apt to presume, was by no means in accordance with the common opinion of his age. The fathers, with the exception, perhaps the single one, of Augustin, had taught the corporeity of the thinking substance. Arnauld seems to consider the doctrine of Descartes as almost a novelty in modern times. "What you have written concerning the distinction between the soul and body appears to me very clear, very evident, and quite divine; and as nothing is older than truth, I have had singular pleasure to see that almost the same things have formerly been very perspicuously and agreeably handled by St. Augustin in all his tenth book on the Trinity, but chiefly in the tenth chapter." But Arnauld himself, in his objections to the Meditations, had put it as at least questionable, whether that which thinks is not something extended, which, besides the usual properties of extended substances, such as mobility and figure, has also this particular virtue and power of thinking. The reply of Descartes removed the difficulties of the illustrious Jansenist, who became an ardent and almost complete disciple of the new philosophy. In a placard against the Cartesian philosophy, printed in 1647, which seems to have come from Revius, professor of theology at Leyden, it is said, "As far as regards the nature of things, nothing seems to hinder but that the soul may be either a substance, or a mode of corporeal substance.' And More, f Dissertation, ubi suprà. h Descartes, ii. 14. Id., x. 73. who had carried on a metaphysical correspondence with Descartes, whom he professed to admire, at least at that time, above all philosophers that had ever existed, without exception of his favourite Plato, extols him after his death in a letter to Clerselier, as having best established the foundations of religion. "For the peripatetics," he says, "pretend that there are certain substantial forms emanating from matter, and so united to it that they cannot subsist without it, to which class these philosophers refer the souls of almost all living beings, even those to which they allow sensation and thought; while the Epicureans, on the other hand, who laugh at substantial forms, ascribe thought to matter itself, so that it is M. Descartes alone, of all philosophers, who has at once banished from philosophy all these substantial forms or souls derived from matter, and absolutely divested matter itself of the faculty of feeling and thinking."k and imagina 95. It must be owned that the firm belief of Descartes in the immateriality of the Ego, or thinking prin- Theory of ciple, was accompanied with what in later times memory would have been deemed rather too great conces- tion. sions to the materialists. He held the imagination and the memory to be portions of the brain, wherein the images of our sensations are bodily preserved; and even assigned such a motive force to the imagination, as to produce those involuntary actions which we often perform, and all the movements of brutes. "This explains how all the motions of all animals arise, though we grant them no * Descartes, x. 386. Even More seems to have been perplexed at one time by the difficulty of accounting for the knowledge and sentiment of disembodied souls, and almost inclined to admit their corporeity. "J'aimerois mieux dire avec les Platoniciens, les anciens pères, et presque tous les philosophes, que les âmes humaines, tous les génies tant bons que mauvais, sont corporels, et que par conséquent ils ont un sentiment réel, c'est à dire, qui leur vient du corps dont ils sont revétus." This is in a letter to Descartes in 1649, which I have not read in Latin (vol. x. p. 249). I do not quite understand whether he meant only that the soul, when separated from the gross body, is invested with a substantial clothing, or that there is what we may call an interior body, a supposed monad, to which the thinking principle is indissolubly united. This is what all materialists mean, who have any clear notions whatever; it is a possible, perhaps a plausible, perhaps even a highly probable, hypothesis, but one which will not prove their theory. The former seems almost an indispensable supposition, if we admit sensibility to phænomena at all in the soul after death; but it is rather, perhaps, a theological than a metaphysical speculation. knowledge of things, but only an imagination entirely corporeal, and how all those operations which do not require the concurrence of reason are produced in us." But the whole of his notions as to the connexion of the soul and body, and indeed all his physiological theories, of which he was most enamoured, do little credit to the Cartesian philosophy. They are among those portions of his creed which have lain most open to ridicule, and wnich it would be useless for us to detail. He seems to have expected more advantage to psychology from anatomical researches than in that state of the science, or even probably in any future state of it, anatomy could afford. When asked once where was his library, he replied, showing a calf he was dissecting, This is my library." His treatise on the passions, a subject so important in the philosophy of the human mind, is made up of crude hypotheses, or at best irrelevant observations, on their physical causes and concomitants. in pineal gland. 96. It may be considered as a part of this syncretism, Seat of soul as we may call it, of the material and immaterial hypotheses, that Descartes fixed the seat of the soul in the conarion, or pineal gland, which he selected as the only part of the brain which is not double. By some means of communication which he did not profess to explain, though later metaphysicians have attempted to do so, the unextended intelligence, thus confined to a certain spot, receives the sensations which are immediately produced through impressions on the substance of the brain. If he did not solve the problem, be it remembered that the problem has never since been solved. It was objected by a nameless correspondent, who signs himself Hyperaspistes, that the soul being incorporeal could not leave by its operations a trace on the brain, which his theory seemed to imply. Descartes answered, in rather a remarkable passage, that as to things purely intellectual, we do not, properly speaking, remember them at all, as they are equally original thoughts every time they present themselves to the mind, except that they are habitually joined, m Descartes was very fond of dissection: C'est un exercice où je me suis souvent occupé depuis onze ans, et je crois qu'il n'y a guère de médecins qui y ait regardé de si près que moi. Vol. viii. p. 100, also p. 174 and 180. |