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is the genuine spirit of philosophy, I perceive a settled determination to attain celebrity by broaching and maintaining with ingenuity, new and strange opinions, and by varnishing over absurdities with the gloss of sophistry.
“But however absurd this doctrine might appear,” says Dr. Reid,“ to the unlearned, who consider the existence of the objects of sense as the most evident of all truths, and what no man in his senses can doubt; the philosophers who had been accustomed to consider ideas as the immediate objects of all thought, had no title to view this doctrine of Berkeley in so unfavourable a light.” In the truth of this opinion, we cannot concur. All the best philosophers had agreed in the belief, although upon different grounds, of the existence of outward objects; and those among the ancients who pretended to doubt their reality, only exposed themselves to ridicule, and their doctrine to contempt. Aristotle, the first among them, was too serious an inquirer into nature, and too profound a thinker to establish any principles, which could lead to such a frivolous and absurd conclusion. In the case of Des Cartes and the Cartesians, perhaps it was naturally to be expected that when they ceased to dogmatise with the schools, and to receive every thing without proof, they should pass into the opposite extreme, and require demonstration for too much, even for those things, which ought to be received up. on the authority of nature, without expecting to have them deduced from the principles of philosophy. As Aristotle remarks, there must be some principles taken for granted in every science, otherwise we must suppose the human mind to be capable of an indefinite advancement in its progress towards ascertaining the grounds of knowledge; and surely no part of our knowledge appears to have a more just title to be received upon trust, than that which flows to us through the channels of sense. Des Cartes, however, chose to simplify his philosophy still more, and commencing with the single assumption, cogito, ergo sum, upon this as a foundation to
erect the superstructure of his system. In doing this, although by a process so simple, he relieved himself at once from the dogmas of the schools; he pushed his principles to excess, as there are many other propositions whose truth as irresistibly flashes upon the mind, and of which no good proof can be given by reason as this celebrated maxim. It is to be expected, therefore, as we really find to be the case, that every argument he has given in demonstration of the existence of an external world, only tends to prove that we should repose confidence in the testimony of the senses. In the beginning of his second part of the Principia Philosophiæ, he thus expresses himself. Etsi nemo non sibi satis persuadeat res materiales existere, quia tamen hoc a nobis paulo ante in dubium revocatum est, et inter primæ nostræ ætatis præjudicia numeratum, nunc opus est, ut rationes investigemus, per quas id certo cognoscatur. Nempe quicquid sentimus, proculdubio nobis advenit a re aliqua, quæ a mente nostra diversa est. Neque enim est in nostra potestate efficere, ut unum potius quam aliud sentiamus; sed hoc a re illa quæ sensus nostros afficit, planè pendet. Quæri quidem potest an res illa sit Deus, an quid a Deo diversum? Sed quia sentimus, sive potuis a sensu impulsi clarè et distinctè percipimus materiam quandam extensam in longum, latum et profundum, cujus variæ partes variis figuris præditæ sunt, ac variis motibus cientur; ac etiam efficiunt ut varios sensus habeamus colorum, odorum, duloris, &c. Si Deus immediatè per se ipsum istius materiæ extensæ ideam menti nostræ exhiberet, vel tantum si efficeret, ut exhiberetur a re aliqua, in qua nihil esset extensionis, nec figuræ, nec motus; nulla ratio potest excogitari cur non deceptor esset putandus. Ipsam enim clarè intelligimus tanquam rem a Deo, et a nobis sive a mente nostra planè diversam; ac etiam clarè viderè nobis videmur, ejus ideam a rebus extra nos positis, quibus omnino similis est, advenire; Dei autem naturæ plane repug. nare ut sit deceptor, jam ante est animadversum. Atque
ideo hic omnino concludendum est, rem quandam extensam, in longum, latum et profundum, omnesque illas proprietates quas rei extensæ convenire clare percipimus habentem, existere. Estque hæc res extensa, quam corpus sive materiam appellamus. I have introduced this paragraph with a double view. In the first place, it explains to us in what Des Cartes supposed the difficulty about our proof of an exterior world to consist; and in the next place, what he imagined would remove that difficulty. As to the first it is evident, instead of the difficulty in the proof of an exterior world consisting, as Dr. Reid maintains, in our perceiving only the idea or image of the outward object, and having no reason from thence to infer its real existence, that he makes it to consist, in our being unable to infer the existence of any object from our perception of it: for although, says he, it be evident when we perceive any object, that our perception must be occasioned by something distinct from ourselves; yet how do we know whether that be God or a substance, extended in length, breadth and depth, as matter appears to be? The only way in which he thought himself able to remove this difficulty, was by asserting that God could be no deceiver, and that he would not perpetually delucle us with unreal visions. It appears, therefore, that Des Cartes, as much disposed as he was, to demand proof of every thing, was no sceptic, and found sufficient reasons for giving credit to the testimony of his senses. He might, of consequence, have justly complained of the perversion of his principles by Berkeley. Mallebranche undoubtedly had less cause of complaint, since he not only rested the belief in an external world, upon insufficient and false grounds, maintaining that we could be assured of it only from revelation; but his chimerical doctrine of seeing all things in God, went directly and unavoidably to its utter exclusion. Whatever, however, might be said by the other philosophers, the injustice and inaccuracy of the observation made of them by Dr. Reid,
that they had no right to complain of the attempt made by Berkeley, when applied to Mr. Locke, are glaringly exhibited. Mr. Locke has not only given the hint to Bishop Berkeley, of the plan which he pursued, but has sketched the character of any one who should attempt to execute it, in colours by no means flattering. In ch. 2, book 4. he says, “ There can be nothing more certain than that the idea we receive from an external object, is in our minds. This is intuitive knowledge. But whether there be any thing more than barely that idea in our minds, whether we can thence certainly infer the existence of any thing without us, which corresponds to that idea, is that, whereof some men think there may be a question made; because men may have such ideas in their minds, when no such thing exists, no such object affects their senses. But here, I think we are provided with an evidence, that puts us past doubting. For I ask any one, whether he be not invincibly conscious to himself of a different perception, when he looks on the sun by day, and thinks on it by night; when he actually tastes worm wood or smells a rose, or only thinks on that savour or odour? We as plainly find the difference there is between any idea revived in our minds by our own memory, and actually coming into our minds by our senses, as we do between any two distinct ideas. If any one say, a dream may do the same thing, and all these ideas may be produced in us, without any external objects, he may please to dream that I make him this answer, 1st. That it is no great matter, whether I remove his scruple or no. Where all is but dream, reasoning and arguments are of no use; truth and knowledge nothing. 2d. That I believe he will allow a very manifest difference between dreaming of being in the fire, and being actually in it.” Again in the same book, ch. 11. “ For I think nobody can in earnest be so sceptical, as to be uncertain of the existence of those things which he sees and feels. At least, he that can doubt so far, whatever he may have with his own
thoughts, will never have any controversy with me, since he can never be sure that I say any thing contrary to his opinion.” We see, therefore, that Mr, Locke pointed out to Berkeley, what might be attempted on this subject; but at the same time certainly gave him no great encouragement to the undertaking, by telling him in very unambiguous terms, that he should consider the person who engaged in it as insane.*
There is a point in this statement of Mr. Locke, as well as in that of Des Cartes before quoted, which is worthy of particular remark, as it relates to the very hinge upon which the controversy with the immaterialists turns. Dr Reid asserts, that since all the philosophers admitted that our ideas of outward objects are the images or representatives of them, and which are the only immediate objects of perception, Berkeley had good ground to infer, since the image alone is perceived, that alone has a real existence. This he considers as an unavoidable inference from the acknowledg. ed principles of the ideal philosophy. Now a moment's examination of what Locke and Des Cartes have just alleged on this subject will convince any one, that these two authors did not consider this as the great difficulty. The ground of Berkeley's scepticism lies much deeper than that which is assigned to it by Dr. Reid. If the doctrine were held, that our ideas are images in the mind, the only immediate objects of perception, it is true that men might say there is no necessity for the existence of the objects, since God by certain laws might produce them in our mind; but the difficulty
* The Count de Buffon very well expresses the difficulty in bis Natural History, where speaking of man, he says—“ As the mind, during sleep, is affected with sensations which are often different from those excited by the actual presence of the objects, is it not natural to think, that the presence of objects is not necessary to the existence of our sensations; and consequently, that both mind and body may exist independent of these objects.” This is the whole difficulty, and as the Count had no hypothesis to serve, he has stated it naturally and truly.