1.  THERE is no part of philosophy which has made less progress among the vulgar, than that which treating of sensible qualities, dismisses them entirely from body, to make them reside in the mind. The most eminent philosophers of antiquity have acknowledged this truth; it sprung naturally from their principles, and they deduce the same consequences from it. Democritus, Socrates, Aristippus, Plato, Epicurus, and Lucretius, have clearly affirmed, that cold and heat, odours and colours, were no other than sensations, excited in our minds, by the different operations of the bodies surrounding us, and acting on our senses. And it is easy to show, that Aristotle himself was of this opinion, “that sensible qualities exist in the mind ;“ though by the obscure manner in which he opens himself, he hath given occasion to believe that he thought otherwise. There are only the schoolmen, who have positively affirmed, that sensible qualities exist in bodies as in minds; that there is in luminous bodies, for example, the very same thing that is in us when we view light. And as the philosophy of the schools had for some ages taken possession of men’s minds, when Descartes, and after him, Mallebranche, arose in opposition to the common prejudices, taking pains to draw the herd of philosophers out of the gross errors wherein they found them involved; it was not perceived, that in this they did nothing but renew the very same truths, which had been taught by Democritus, Plato, Aristippus, and Sextus Empiricus, supporting them likewise by the very same arguments, though sometimes farther extended. Hence all the honour has been ascribed to these moderns, as if the error they attacked had been that of all ages; nobody designing to search any deeper, whether in reality, it was so or not. For had they given any attention to what the ancients had advanced, or consulted their writings, they would soon have found that some of them, not only stripped body of every power of exciting opinions in us, but even sometimes called in question its very existence. Yet this indolence in ascertaining the origin of our improvements, was not entirely universal. Gassendi had published a tract upon sensible qualities, and given also an abridgement of the Pyrrhonic philosophy respecting this subject, before ever Descartes attempted it; so that even among the moderns themselves, Descartes is not the first who clearly distinguished between the properties of spirit and body. And as to the ancients, a brief narrative of what Descartes and Mallebranche have said, compared with what those ancients taught, will quickly put the reader in a condition of deciding to whom that discovery ought to be attributed.

2.  Descartes begins with remarking, that every one is accustomed from his infancy, to look upon whatever he perceives by his senses as existing out of his mind ; and having an entire resemblance to the perceptions which he finds there. Observing the colour of any object, for instance, we think we see something without ourselves, and residing in the objects, exactly resembling our idea of it; and, we acquire such a habit of judging in this manner, that we never entertain any doubt. This is the case of all our sensations; we seldom imagine that they exist only in the mind, but rather in our hand or foot, or some other part of our body. There is nothing however more certain, than that the pain which we feel in our foot, is nothing but what the mind perceives as there ; in the same manner as the light we see as it were in the sun, is an idea raised by it in our minds. In the same manner we say, we perceive colours, or discern odours in objects; when these sensations arise in us from something or other in those objects. Such are the misconceptions of our infant state, from which we can hardly rescue ourselves even in advanced life.

3.   Mallebranche seized this idea of Descartes, and more fully opened it. In his celebrated work, the research into truth, he begins with discovering that the source of our error is in the abuse of our liberty, and the precipitation with which we form judgment; insomuch, that our senses could not impose on us, were it not for our rashness, For example, when we see light, it is certain we do so; when we feel heat, there is no mistake in imagining we do; but we deceive ourselves when we fancy, that the heat and odours we perceive are external to the mind that feels them. He then combats the errors arising from our way of judging; and having stripped the body of its sensible qualities, instructs us how mind and body co-operate to produce our sensations, and how we accompany them with false judgments. He blames those who always judge of objects by the sensations they excite and by an appeal to their own feelings; for the feelings of all men being different, though things themselves continue the same, they must judge variously as they are affected, but ought not to ascribe the diversity of affections to the objects themselves.

4.  Were we to bring into review all the ancients have taught on this subject, we should be surprised at the clearness with which they have explained themselves, and at a loss to account how opinions came to be taken for new, which had been already illustrated in their writings, with such force and precision. It cannot so much as be said, that the moderns have given a new turn to these opinions; for they not only reason upon the same principles, but employ the very same comparisons in proof of them.

5.   Democritus was the first who disarrayed body of its sensible qualities. That great man, who admitted only of atoms and space as the principles of things. differed from all who had preceded him in that opinion, in that he affirmed, atoms were void of qualities ; and in this he was followed by Epicurus. He derived qualities from the different order and disposition of the atoms among themselves, as well from their diversity of figure; which, according to him, was the cause of all the various changes and modifications in nature; some of them being round, others angular, some straight, some pointed, some crooked, &c. “ Thus the first elements of things having in them neither whiteness nor blackness, sweetness, nor bitterness, heat nor cold, nor any other quality ; it follows, that colour, for example, exists Only in our perception of it; as also, that bitterness, and sweetness, which exist only in being perceived, are the consequences of the different manners in which we ourselves are affected by the bodies surrounding us, there being nothing in its own nature yellow, or white, or red, sweet or bitter."

6.   Sextus Empiricus, explaining the doctrine of Democritus, says, “that sensible qualities,” according to that philosopher, “have nothing of reality but in the opinion of those who are differently affected by them, according to the different dispositions of their organs ; and that from this difference of disposition arise the perceptions of sweet and bitter, heat and cold ; and also, that we do not deceive ourselves in affirming that we feel such impressions ; but in concluding that exterior objects, must have in them something analagous to our feelings.”

7.   Protagoras, the disciple of Democritus, says, that in man is contained the rule or measure of every thing ; that the whole existence of external things consists in the impression we perceive in ourselves; insomuch that what is imperceptible, has not the consequences of his system; for admitting, with his master, the perpetual mutability of matter, which occasioned a constant change in things; he then added, that whatsoever we see, apprehend, or touch, are just as they appear; and that the only true rule or criterion of things, was in the perception men had of them. I leave the reader to judge, whether Protagora’s manner of thinking might not have transmitted to Berkely the idea of a system, which he with so much subtilty hath maintained “that there is nothing in external objects, but what the sensible qualities existing in our minds induce us to imagine, and of course that they have no other manner of existence; there being no other substratum for them, than the minds by which they are perceived: not as modes or qualities belonging to themselves, but as objects of perception to whatever is percipient.”

8.  We should think we were listening to the two modern philosophers, when we hear Aristippus exhorting men “to be upon their guard with respect to the reports of sense, because it does not always yield just information; for we do not perceive exterior objects as they are in themselves but only as they affect us. We know not of what colour or smell they may be, these being only affections in ourselves. It is not the objects themselves that we are enabled to comprehend, but are confined to judge of them only by the impressions they make upon us; and the wrong judgments we form of them in this respect, is the cause of all our errors. Hence, when we perceive a tower which appears round, or an oar which seems crooked in the water; we may say that our senses intimate so and so, but ought not to affirm, that the distant tower is really round, or the oar in the water crooked: it is enough, in such a case, to say, that we receive the impression of ,roundness from the tower, and of crookedness from the oar; but it is neither necessary nor proper to affirm, that the tower is really round, or the oar broken; for a square tower may appear round at a distance, and a straight stick always seems crooked in the water.”

9.   Aristippus says farther, “there is not in man any faculty that can judge of the truth of things, any farther than that men have given common names to their own apprehensions. Thus every body talks of whiteness and sweetness, but they have no common faculty to which they can with certainty refer impressions of this kind. Every one judges by his own apprehensions, and nobody can affirm that the sensation which he feels when he sees a white object, is the same with what his neighbour experiences in regard to the same object; and because the powers of apprehension are not entirely the same in all, it is temerity in us to assert, that what appears in such or such a manner to one, must needs do so to every body else: for one may be so constituted, that the objects which offer themselves to his eye may appear white, while to those of a man differently constituted they seem yellow; as is manifest in those who have the jaundice, or any other natural diversity of discernment, and who by reason of the different contexture of their organs, are incapable of receiving from the same things, the same impressions that others do. Thus he who has large eyes, will see objects in a different magnitude from him whose eyes are little; and he who bath blue eyes, discerns them under different colours from him who hath gray.”

10.   Plato, following Protagoras, clearly distinguishes between sensible qualities, and the objects which cause-them. He observes, that the same wind appears cold to one, and hot to another; to one soft, and to another rough: but “that we ought not thence to conclude, that the wind is in itself hot and cold at the same time ; but to say with Protagoras, that he who is hot, feels it hot,” &c.

11.   I come now to Epicurus, whose doctrine is explained with the greatest exactness by Plutarch, but above all by Diogenes Laertius. This philosopher, admitting the principles of Democritus, hath thence deduced the most natural consequences : “that atoms are all of the same nature, and differ only in figure, magnitude, and weight, and that in the constitution of every thing, they bear some affinity to its principal properties, such as roundness, bulk, &c. For colour, says he, cold and heat, and the other sensible qualities, are not inherent in the atoms, but the result of their assemblage : and the difference between them flows from the diversity of their size, figure, and arrangement: insomuch, that any number of atoms in one disposition, creates one Sort of sensation ; and in another, another: but their own primary nature remains always the same, because being solid and uncompounded, no parts transpire, otherwise nature would not be in the main fixed and stable ; and it is from the permanency of the properties essential to atoms of matter, that the different sensations arise, which the same. objects produce in animals of different species, and in men of different constitutions ; for each have in the organs of sight, hearing, and. the ether senses, an innumerable multitude of pores differently sized and situated; these are variously adapted and proportioned for the reception of the small corpuscles, which easily insinuate themselves into some, and with difficulty into others, (according to the analogy between them and the pores, and the variety of contexture in the parts) and of course must produce different impressions.”

12.   So that the senses do not deceive us, for they are not judges of the nature of things; but serve only to inform us of the connexion and relation between the bodies surrounding us and our own, in subserviency to our happiness in this life: “whence it is obvious, that our sensations are always true, though the judgments we many times form respecting their objects are sometimes false :“ as must always be the case, whenever we alter those objects themselves which are the exterior causes of our sensations, by either adding something foreign to them or retrenching from them, what is properly their own. "If any think they are imposed upon by the different appearances which result from one and the same object; as, for example, when a body seen at a distance appears of one colour, and when nigh of another; it is themselves who are guilty of the deception, in imagining that the one appearance is true, and the other illusory; for in that, they form a false judgment, not rightly considering the nature of things ; whereas, they ought, on the contrary, to have concluded that both colours were true, though different, occasioned by the change of situations in which they were viewed, which produced two sensations not the same, but equally true. Whence it also happens, that it is not the sound in the brass that is beaten, nor the voice itself of a person who sings, that are the objects of our perception, but only that which acts upon our ear; for one and the same thing cannot be in two different places at once. And as no man says, that his judgment is imposed upon, because a sound strikes him more feebly at a distance, than when he hath approached the place whence it comes: neither can we say, that our sight illudes us, when at a distance, a tower appears small and round, which upon our approach to it, would be found large and square: for the representative size of the object is in exact proportion to that of the angle formed by it in the eye, which varies according to the difference of the distance. In a word, the use of the senses is to represent objects to us under certain appearances; but not at all to judge what they are in themselves: and hence our sensations are always true; error being only the result of our judgment.”

13.  1 have been the more large on this subject, because it is one of the most proper to prove the truth of my proposition, “that the moderns have often enriched themselves with the spoils of the ancients, without having done them the honour of any acknowledgement.” With reason have we praised Descartes and Mallebranche, for having treated this matter with so much penetration. But they have scarcely advanced any thing but what had been said before by those ancient philosophers, whom I have been quoting.

Chapter 7 - Of Animated Nature

Chapter 7