SECTION IV.

THAT COLOUR IS A QUALITY OF BODIES, NOT A SENSATION OF THE MIND.

By colour, all men, who have not been tutored by modern philosophy, understand, not a sensation of the mind, which can have no existence when it is not perceived, but a quality or modification of bodies, which continues to be the same, whether it is seen or not. The 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. For when I view this scarlet rose through a pair of green spectacles, the appearance is changed, but I do not conceive the colour of the rose changed. To a person in the jaundice, it has still another appearance; but he is easily convinced, that the change is in his eye, and not in the colour of the object. Every different degree of light makes it have a different appearance, and total darkness takes away all appearance, but makes not the least change in the colour of the body. We may, by a variety of optical experiments, change the appearance of figure and magnitude in a body, as well as that of colour; we may make one body appear to be ten. But all men believe, that as a multiplying glass does not really produce ten guineas out of one, nor a microscope turn a guinea into a ten pound piece, so neither does a coloured glass change the real colour of the object seen through it, when it changes the appearance of that

colour.

The common language of mankind shows evidently, that we ought to distinguish between the colour of a body, which is conceived to be a fixed and permanent quality in the body, and the appearance of that colour to the eye, which may be varied a thousand ways, by a variation of the light of the medium, or of the eye itself. The permanent colour of the body is the cause, which, by the mediation of various kinds or degrees of light, and of various transparent bodies interposed, produces all this variety of appearances. When a coloured body is presented, there is a certain apparition to the eye, or to the mind, which we have called the appearance of colour. Mr. Locke calls it an idea; and indeed it may be called so with the greatest propriety. This idea can have no existence but when it is perceived. It is a kind of thought, and can only be the act of a percipiant or thinking being. By the constitution of our nature, we are led to conceive this idea as a sign of something external, and are impatient till we learn its meaning. A thousand experiments for this purpose are made every day by children, even before they come

to the use of reason. They look at things, they handle them, they put them in various positions, at different distances, and in different lights. The ideas of sight, by these means, come to be associated with, and readily to suggest, things external and altogether unlike them. In particular, that idea which we have called the appearance of colour, suggests the conception and belief of some unknown quality, in the body which occasions the idea; and it is to this quality, and not to the idea, that we give the name of colour. The various colours, although in their nature equally unknown, are easily distinguished when we think or speak of them, by being associated with the ideas which they excite. In like manner, gravity, magnetism, and electricity, although all unknown qualities, are distinguished by their different effects. As we grow up, the mind acquires a habit of passing so rapidly from the ideas of sight to the external things suggested by them, that the ideas are not in the least attended to, nor have they names given them in common language.

When we think or speak of any particular colour, however simple the notion may seem to be, which is presented to the imagination, it is really in some sort compounded. It involves an unknown cause, and a known effect. The name of colour belongs indeed to the cause only, and not to the effect. But as the cause is unknown, we can form no distinct conception of it, but by its relation to the known effect. And therefore both go together in the imagination, and are so closely united, that they are mistaken for one simple object of thought. When I would conceive those colours of bodies which we call scarlet and blue; if I conceived them only as unknown qualities, I could perceive no distinction between the one and the other. I must therefore, for the sake of distinction, join to each of them, in my imagination, some effect or some relation that is peculiar. And the most obvious distinction is, the appearance which one and the other makes to the eye. Hence the appearance is, in the imagination, so closely united with the quality called a scarlet colour, that they are apt to be mistaken for one and the same thing, although they are in reality so different and so unlike, that one is an idea in the mind, the other is a quality of body.

I conclude, then, that colour is not a sensation, but a secondary quality of bodies, in the sense we have already explained; that it is a certain power or virtue in bodies, that in fair daylight exhibits to the eye an appearance, which is very familiar to us, although it hath no name. Colour differs from other secondary qualities in this, that whereas the name of the quality is sometimes given to the sensation which indicates it, and is occasioned by it, we never, as far as I can judge, give the name of colour to the sensation, but to the quality only. Perhaps the reason of this may be, that the appearances of the same colour are so va

rious and changeable, according to the different modifications of the light, of the medium, and of the eye, that language could not afford names for them. And indeed they are so little interesting, that they are never attended to, but serve only as signs to introduce the things signified by them. Nor ought it to appear incredible, that appearances so frequent and so familiar should have no names, nor be made objects of thought; since we have before shown, that this is true of many sensations of touch, which are no less frequent, nor less familiar.

SECTION V.

AN INFERENCE FROM THE PRECEDING.

FROM what hath been said about colour, we may infer two things. The first is, that one of the most remarkable paradoxes of modern philosophy, which hath been universally esteemed as a great discovery, is, in reality, when examined to the bottom, nothing else but an abuse of words. The parodox I mean is, that colour is not a quality of bodies, but only an idea in the mind. We have shown, that the word colour, as used b、 the vulgar, cannot signify an idea in the mind, but a permanent quality of body. We have shown, that there is really a permanent quality of body, to which the common use of this word exactly agrees. Can any stronger proof be desired, that this quality is that to which the vulgar give the name of colour? If it should be said, that this quality, to which we give the name of colour, is unknown to the vulgar, and therefore can have no name among them; I answer, it is indeed known only by its effects; that is by its exciting a certain idea in us: but are there not numberless qualities of bodies, which are known only by their effects, to which, notwithstanding, we find it necessary to give names? Medicine alone might furnish us with a hundred instances of this kind. Do not the words astringent, narcotic, epispastic, caustic, and innumerable others, signify qualities of bodies, which are known only by their effects upon animal bodies? Why then should not the vulgar give a name to a quality, whose effects are every moment perceived by their eyes? We have all the reason therefore, that the nature of the thing admits, to think that the vulgar apply the name of colour to that quality of bodies which excites in us what the philosophers call the idea of colour. And that there is such a quality in bodies, all philosophers allow, who allow that there is any such thing as body. Philosophers have thought fit to leave that quality of bodies, which the vulgar call colour, without a name, and to give the name colour to the idea or appearance, to which, as we have shown, the vulgar

give no name, because they never make it an object of thought or reflection. Hence it appears, that when philosophers affirm that colour is not in bodies, but in the mind; and the vulgar affirm, that colour is not in the mind, but is a quality of bodies; there is no difference between them about things, but only about the meaning of a word.

The vulgar have undoubted right to give names to things which they are daily conversant about; and philosophers seem justly chargeable with an abuse of language, when they change the meaning of a common word, without giving warning.

If it is a good rule, to think with philosophers, and speak with the vulgar, it must be right to speak with the vulgar, when we think with them, and not to shock them by philosophical paradoxes, which, when put into common language, express only the common sense of mankind.

If you ask a man that is no philosopher, what colour is? or, what makes one body appear white, another scarlet? he cannot tell. He leaves that inquiry to philosophers, and can embrace any hypothesis about it, except that of our modern philosophers, who affirm, that colour is not in body, but only in the mind.

Nothing appears more shocking to his apprehension, than that visible objects should have no colour, and that colour should be in that which he conceives to be invisible. Yet this strange pa

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radox is not only universally received, but considered as one of the noblest discoveries of modern philosophy. The ingenious Addison, in the Spectator, No. 413, speaks thus of it. "I have here supposed, that my reader is acquainted with that great modern discovery, which is at present universally acknowledged by all the inquirers into natural philosophy, namely, that light and colours, as apprehended by the imagination, are only ideas in the mind, and not qualities that have any existence in matter. As this is a truth, which has been proved incontestably by many modern philosophers, and is indeed one of the finest speculations in that science, if the English reader would see the notion explained at large, he may find it in the eighth chapter of the second book of Locke's Essay on the Human Understanding."

Mr. Locke and Mr. Addison are writers who have deserved so well of mankind, that one must feel some uneasiness in differing from them, and would wish to ascribe all the merit that is due to a discovery upon which they put so high a value. And indeed it is just to acknowledge that Locke, and other modern philosophers, on the subject of secondary qualities, have the merit of distinguishing more accurately than those that went before them, between the sensation in the mind, and that constitution or quality of bodies which gives occasion to the sensation. They have shown clearly, that these two things are not only distinct, but altogether unlike: that there is no similitude between the effluvia of an odorous body, and the sensation of smell, or between

the vibrations of a sounding body, and the sensation of sound; that there can be no resemblance between the feeling of heat and the constitution of the heated body which occasions it: or between the appearance which a coloured body makes to the eye, and the texture of the body, which causes that appearance. Nor was the merit small of distinguishing these things accurately; because, however different and unlike in their nature, they have been always so associated in the imagination, as to coalesce as it were into one two-faced form, which, from its amphibious nature, could not justly be appropriated either to body or mind; and until it was properly distinguished into its different constituent parts, it was impossible to assign to either their just shares in it. None of the ancient philosophers had made this distinction. The followers of Democritus and Epicurus conceived the forms of heat, and sound, and colour, to be in the mind only, but that our senses falaciously represented them as being in bodies. The Peripatetics imagined, that those forms are really in bodies; and that the images of them are conveyed to the mind by our senses.

The one system made the senses naturally fallacious and deceitful; the other made the qualities of body to resemble the sensations of the mind. Nor was it possible to find a third, without making the distinction we have mentioned; by which indeed the errors of both these ancient systems are avoided, and we are not left under the hard necessity of believing, either, on the one hand, that our sensations are like to the qualities of body, or, on the other, that God hath given us one faculty to deceive us, and another to detect the cheat.

We desire, therefore, with pleasure, to do justice to the doctrine of Locke, and other modern philosophers, with regard to colour, and other secondary qualities, and to ascribe to it its due merit, while we beg leave to censure the language in which they have expressed their doctrine. When they had explained and established the distinction between the appearance which colour makes to the eye, and the modification of the coloured body, which by the laws of nature, causes that appearance; the question was, whether to give the name of colour to the cause, or to the effect? By giving it, as they have done, to the effect, they set philosophy apparently in opposition to common sense, and expose it to the ridicule of the vulgar. But had they given the name of colour to the cause, as they ought to have done, they must then have affirmed, with the vulgar, that colour is a quality of bodies; and that there is neither colour, nor any thing like it, in the mind. Their language, as well as their sentiments, would have been perfectly agreeable to the common apprehensions of mankind, and true philosophy would have joined hands with common sense. As Locke was no enemy to common sense, it may be presumed, that, in this instance, as in some