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motwithstanding its unpromising subject, was evidently the work of an author, deeply tainted, indeed, with the prejudices of his country and of his age, but of no inconsiderable learning and ingenuity. The treatise I allude to is entitled, “AEYTEPoskoTIIA, “ or, a Brief Discourse concerning the Second Sight, common** ly so called. By the Rev. Mr John Frazer, deceased, late “minister of Tirrie and Coll, and Dean of the Isles.” (Edinburgh, printed by Mr Andrew Symson, 1707.) The passage seems to me to deserve preservation, as a memorial of the state of Scottish philosophy towards the end of the seventeenth century; and I willingly give it a place here, as the book from which it is extracted is not likely to fall in the way of many of my readers. After mentioning a variety of anecdotes, concerning the illusions of imagination to which hypochondriacal persons are liable, when in a state of solitude, the author proceeds thus:– “If you will ask, how cometh this to pass : Take notice of “ the following method, which I humbly offer to your consider“ation. Advert, in the first place, that visible ideas or species = “ are emitted from every visible object to the organ of the eye, “representing the figure and colour of the object, and bearing “ along with it the proportion of the distance; for sure, the ob. “jects enter not the eye, nor the interjacent track of ground. “And a third thing, different from the eye and the object, and “ the distant ground, must inform the eye. The species are con“veyed to the brain by the optic nerve, and are laid up in the “ magazine of the memory; otherwise, we should not remember “ the object any longer than it is in our presence, and a remem“bering of those objects is nothing else but the fancy's receiving, “ or more properly, the soul of man by the fancy receiving, “ these intentional species formerly received from the visible ob“ject into the organ of the eye, and recondited into the seat of “ the memory. Now, when the brain is in a serene temper, “ these species are in their integrity, and keep their rank and file “ as they were received; but when the brain is filled with gross “ and flatuous vapours, and the spirits and humours enraged, “ these ideas are sometimes multiplied, sometimes magnified, “ sometimes misplaced, sometimes confounded by other species of “ different objects, &c. &c. and this deception is not only inci“dent to the saucy, but even to the external senses, particularly “ the seeing and hearing. For the visus, or seeing, is nothing “ else but the transition of the intentional species through the “crystalline humour to the retiform coat of the eye, and judged

* In consequence of the growing influence of the Cartesian philosophy, these words were then beginning to be regarded as syuonymous.

“ by the common sense, and conveyed by the optic nerve to the “fancy.” o: o o: #

“Now, if these species formerly received and laid up in the “brain, will be reversed back from the same to the retiform coat “ and crystalline humour as formerly, there is, in effect, a lively “ seeing and perception of the object represented by these species, “ as if de novo the object had been placed before the eye; for “ the organ of the eye had no more of it before than now it has. “Just so with the hearing : it is nothing else but the receiving of “ the audible species to that part of the ear that is accommodated “for hearing; so that when the species are retracted from the “brain to their proper organs (for example, the ear and the eye), “hearing and seeing are perfected, as if the objects had been pre“ sent to influence the organ de novo. And it is not to be “ thought that this is a singular opinion. For Cardanus, an “ eminent author of great and universal reading and experience, “maintains this reversion of the species, and attributes his own “ vision of trees, wild beasts, men, cities, and instructed battles, “ musical and martial instruments, from the fourth to the seventh “ year of his age, to the species of the objects he had seen for“merly, now retracted to the organ of the eye; and cites Aver“roes, an author of greater renown, for the same opinion.”See Cardanus de Subtilitate Rerum, p. 301.

“And it seems truly to be founded upon relevant grounds. I “ have observed a sick person that complained of great pain and “ molestation in his head, and particularly of piping and sweet “singing in his ears; which seems to have been caused by the “species of piping and singing which he had formerly heard; but “were now, through the plethory of his head, forced out of the “brain to the organ of the ear, through the same nerve by which “ they were received formerly; and why may not the same befal “ the visible species as well as the audible? which seems to be “confirmed by this optic experiment : Take a sheet of painted “ paper, and fix it in your window, looking steadfastly to it for a “considerable time; then close your eyes very strait, and open “ your eyes suddenly, you will see the paintings almost as lively “ as they were in the painted sheet, with the lively colours. This “compression of the eyes, by consent causes a compression of “ the whole brain, which forces back the visible species of the “ painted sheet to the organ of the eye through the optic nerve, “ which will presently evanish if the reflectant did not help to “ preserve them. You may see then how much of these repre“sentations may be within ourselves, abstracting from any exter“nal agent or object, without the eye to influence the same.”

Were it not for the credulity displayed by Mr Frazer, in various parts of his book, one would almost be tempted to consider

the foregoing theory as the effort of a superior mind combating the superstitious prejudices of his age, with such weapons as the erroneous philosophy of that age could supply. Perhaps the spirit of the times did not allow him to carry his scepticism farther than he did. A Lord President of our Supreme Court in Scotland (one of the most eminent and accomplished men whom this country has produced) is said to have been an advocate for this article of popular faith more than fifty years afterwards.

- Note (I.) p. 125.

In the passage from Locke, quoted in the foot note, p. 124, a hint is given (very unworthy of his good sense) towards a new theory of the creation of matter. It is a remarkable circumstance, that a theory on the same subject was suggested to Priestley by certain speculations of his own, approaching very nearly to the doctrines of Boscovich; a coincidence which strikes me as a strong additional presumption in favour of that interpretation which I have given to Locke's words.

“I will add in this place, though it will be considered more “fully hereafter, that this supposition of matter having (besides “extension) no other properties but those of attraction and re“ pulsion, greatly relieves the difficulty which attends the suppo“sition of the creation of it out of nothing, and also the continual “moving of it, by a being who has hitherto been supposed to “ have no common property with it. For, according to this hy“ pothesis, both the creating mind, and the created substance, “are equally destitute of solidity or impenetrability; so that there “can be no difficulty whatever in supposing that the latter may “ have been the offspring of the former.”—Disquisitions on Matter and Spirit, Vol. I. p. 23. (Birmingham, 1782.)

Note (K.) p. 148. Notwithstanding the apology which I have offered for the word instinct, as it has been sometimes employed by writers on the Human Mind, I am perfectly sensible that it has been used, on various occasions, even by our most profound reasoners, with too great a degree of latitude. Examples of this might be produced, both from Mr Hume and Mr Smith ; but I shall confine myself, in this note, to a passage from Dr Reid (by whose phraseology I was led to introduce the subject at present), in which he gives the name of instinct to the sudden effort we make to recover our balance, when in danger of falling ; and to certain other instantaneous exertions which we make for our own preservation, in circumstances of unexpected danger.—(See his Essays on the Active Powers of Man, p. 174, 4to edit.) In this particular instance, I agree perfectly (excepting iu one

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single point) with the following very judicious remarks long age made by Gravesande: “Il y a quelque chose d'admirable dans le moyen ordinaire “ dont les hommes se servent, pour s'empêcher de tomber: car “ dans le tems que, par quelque mouvement, le poids du corps “s'augmente d'un cóté, un autre mouvement rétablit l'equilibre “ dans l'instant. On attribue communément la chose à un in“stinct naturel, quoiqu'il faille necessairement l'attribuer à un art “ perfectionné par l'exercice. “Les enfans ignorent absolument cet art dans les premières ** années de leur vie; ils l'apprennent peu ä peu, et s'y persec. “tionnent, parce qu'ils ont continuellement occasion de s'y ex“ercer; exercice qui, dans la suite, n'exige presque plus aucune “ attention de leur part; tout comme un musicien remue les “doigts, suivant les regles de l'art, pendant qu'il apperçoit à “ peine qu'il y fasse la moindre attention."—Oeuvres Philosophiques de M. 'SGravesande, p. 121. Seconde Partie. Amsterdam, 1774. The only thing I am disposed to object to in this extract, is that clause where the author ascribes the effort in question to an art. Is it not manifestly as wide of the truth to refer it to this source as to pure instinct: The word art implies intelligence; the perception of an end, and the choice of means. But where is there any appearance of either, in an operation common to the whole species (not excluding the idiot and the insane);-and which is practised as successfully by the brutes, as by those who are possessed of reason 2 I intend to propose some modifications of the usual modes of speaking concerning this class of phenomena, when I come to contrast the faculties of Man with those of the lower animals.

Note (L.) p. 153.

Want of room obliges me to omit, at present, the illustrations destined for this note; and to refer to some remarks on secondary qualities, in the Philosophy of the Human Mind. See note (P.) at the end of that work; where I have attempted to explain the reference we make of the sensation of colour to the external object; the only difficulty which the subject seems to me to present, and of which neither Dr Reid nor Mr Smith have been sufficiently aware. (See Reid's Inquiry into the Human Mind; and the Essay on the External Senses, in Mr Smith's Posthumous Work.) Both of these writers have, in my opinion, been led to undervalue this part of the Cartesian Philosophy, by the equivocal use made in the common statements of it, of the names of see condary qualities; a circumstance which had long before been ably commented on by Malebranche. D’Alembert saw the difficulty in all its extent, when he observed (speaking of the sensation of colour) : “Rien n'est peut-être plus extraordinaire dans ** les operations de notre ame, que de la voir transporter hors ** d’elle-même et étendre, pour ainsi dire, ses sensations sur une ** substance à laquelle elles me peuvent appartenir.”” Herkeley has made a dexterous and amusing use of this very curious mental phenomenon, to prove that his scheme of idealism was perfectly consonant to the common apprehensions of manRind. ** Perhaps, upon a strict inquiry, we shall not find, that even ** those who from their birth have grown up in a continued habit ** of seeing, are irrecoverably prejudiced on the other side, to wit, ** in thinking what they see to be at a distance from them. For ** at this time it seems agreed on all hands, by those who have ** had any thoughts of that matter, that colours, which are the ** proper and immediate objects of sight, are not without the ** mind. But then it will be said, by sight we have also the ideas * of extension, and figure, and motion; all which may well be “ thought without, and at some distances from the mind, though “colour should not. In answer to this, I appeal to any man's “experience, whether the visible extension of any object doth ** not appear as near to him as the colour of that object; nay, ** whether they do not both seem to be in the very same place. * Is not the extension we see coloured, and is it possible for us, ** so much as in thought, to separate and abstract colour from “extension ? Now, where the extension is, there surely is the ** figure, and there the motion too.—I speak of those which are

“ perceived by sight.”—Essay towards a new Theory of Vision, p. 255.

Note (M.) p. 158.

I intended to have introduced here some doubts and queries with respect to the origin, or rather to the history of the notion of Extension; not with any view to an explanation of a fact which 1 consider, with the eminent philosophers referred to in the text, as altogether unaccountable; but to direct the attention of my readers to a more accurate examination than has been hitherto attempted, of the occasions on which this notion or idea is at first formed by the mind. Whatever light can be thrown on this very obscure subject may be regarded as a valuable accession to the natural history of the human understanding.

It was long ago remarked by Dr Reid (and, indeed, by other writers of a still earlier date), that to account for the idea of Extension by the motion of the hand, is a paralogism, as this supposes a previous knowledge of the existence of our own bodies.

* In the Dissertation prefixed to the First Volume of the Supplement to the Encyclopaedia Britaunica, I have endeavoured to throw some additional light on the difficulty here remarked by D'Alembert. See pp. 98, 99, 100, 101, 102, of the Dissertation, and also Note M, at the end of it,

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