QUALITY is a word which, as used in philosophical disquisitions, cannot be explained by any periphrasis. That which is expressed by it must be brought into the immediate view of the senses or intellect, and the name properly applied, or he who is a stranger to the .word will never be made to comprehend its meaning. Aristotle, who treated it as a general conception, second in order amongst the ten predicaments or categories, gives several characters of it; but though they are all in some respects just, no man could from them, without other assistance, learn what quality is.

When a man comprehends, by means of his senses and intellect, what it is that the word quality denotes, he will indeed perceive that the first of these characters is applicable to some qualities and not to others; that the second is more applicable to quantity than to quality; and that, it is only the third which can with propriety be considered as 1 the general characteristic of this predicament. Thus, when we have learned by our sense of sight that whiteness is a quality of snow, and blackness of coal; and, by means of observation and reflection, that wisdom is a quality of one man, and folly of another; we must admit that the sensible quality of the snow is contrary to that of the coal, and that the intellectual quality of wisdom is contrary to that of folly. There is, however, no contrariety between wisdom and whiteness or blackness, nor between hardness or softness and any particular colour; for sensible and intellectual qualities can never be compared, and it is not easy, if indeed it be possible, to make a comparison between qualities perceptible only by different senses. Nay, amongst qualities perceptible by the same sense, we often meet with a difference where there is no contrariety; for though the figure of a cube is different from that of a sphere, and the figure of a square from that of a circle, the sphere is not contrary to the cube, nor the circle to the square.

His second characteristic of this genus is still less proper than the first. It is indeed true that some qualities admit of intension and remission; for snow is whiter than paper, and one woman is handsomer than another; but of the species of quality called figure we cannot predicate either more or less. A crown-piece may have as much of the circular quality in it as the plane of the equator, and a musket-bullet as much of the spherical quality as the orb of the sun. It is indeed a property of all quantity to admit of intension and remission; and therefore this ought to have been given as the character, not of the second, but of the third category.

That it is only from a comparison of their qualities that things are denominated like or unlike, or that one thing cannot resemble another but in some quality, is indeed a just ohservation. We know nothing directly except qualities sensible and intellectual (see Metaphysics) ; and as these have no resemblance to each other, we conclude that body or matter, the subject of the former, is a being unlike mind, the subject of the latter. Even of bodies themselves we can say that one is like or unlike another only by virtue of their qualities. A ball of ivory resembles a ball of snow in its figure and colour, but not in its coldness or hardness; a ball of lead may resemble a ball of snow in its figure and coldness, but not in its colour; and a cube of ivory resembles not a ball of lead either in figure, colour, or coldness. The mind of a brute resembles that of a man in its powers of sensation and perception, but does not resemble it in the powers of volition and reasoning; or at least the resemblance, in this latter instance, is very slight. All bodies resemble one another in being solid and extended, and all minds in being more or less active. Likeness or unlikeness, therefore, is the universal characteristic of the category quality.

Aristotle has other speculations respecting quality which are worthy of notice. He distinguishes between qualities which are essential and those which are accidental, between qualities which are natural and those which are acquired; and he speaks of the qualities of capacity and those of completion. Extension and figure in general are qualities essential to all bodies; but a particular extension, such as an inch or an ell, and a particular figure, such as a cube or a sphere, are qualities accidental to bodies. Amongst the natural qualities of glass it is one to transmit objects of vision; but to enlarge these objects is an adventitious or acquired quality. The same quality may be natural in one substance, as attraction in the magnet; and acquired in [7:18:774]another, as the same attraction in the magnetic bar. Docility may be called a quality natural to the mind of man, science an acquired one. To understand what he means by qualities of capacity and completion, it may be sufficient to observe, that every piece of iron has the qualities of a razor in capacity, because it may be converted into steel, and formed into a razor; and when it is so formed, it has, in the language of this sage, the quality of a razor in completion. Amongst the qualities of capacity and completion, the most important, and what may lead to interesting speculations, is the reasoning faculty of man. A capacity of reasoning is essential to the human mind; but the completion of this capacity or actual reasoning is not, otherwise infants and persons asleep would be excluded from the human species.

Mr Locke has puzzled his readers with a question respecting the species of an idiot or a changeling, w horn he pronounces to be something between a man and a brute.^[1. Book iv. chap. 4, § 13, &c. ] It is not often that we feel ourselves inclined to regret Locke’s ignorance of Aristotle’s distinctions; but we cannot help thinking, that had the British philosopher attended to the Stagyrite’s account of qualities in capacity and qualities in completion, this perplexing question would never have been started. It is justly observed in the Essay upon Human Understanding, that of real essences we know nothing, but that every man selects a certain number of qualities which he has always perceived united in certain beings, and, forming these into one complex conception, gives to this conception a specific name, which he applies to every being in which he finds those qualities united. This is undoubtedly the process of the mind in forming genera and species; and as the excellent author refuses the name of man to the changeling, it is obvious that the complex conception, to which he gives that name, must imply rationality, or the actual exercise of reason. But this limitation will exclude many beings from the species man, whom Mr Locke certainly considered as men and women. Not to mention infants and persons in sound sleep, how shall we class those who, after having lived thirty or forty years in the full exercise of reason, have been suddenly or by degrees deprived of it by some disorder in the brain?

From Marlborough’s eyes the streams of dotage flow, And Swift expires a driveller and a show.

But were the hero and the wit in those deplorable circumstances excluded from the human species, and classed between men and brutes? No, surely; they were both acknowledged to be men, because they were known to have the quality of reason in what Aristotle would have called capacity. Their dotage and drivelling originated from some disorder in their bodies, probably in the region of the brain; and Locke himself contends that no defect in body is sufficient to degrade a person from the rank of manhood. Again, lunatics have the exercise of reason, except at new and full moon. Are these unhappy beings sometimes men and sometimes a species by themselves between men and brutes?

It appears, therefore, that not the actual exercise of reason, but reason in capacity, ought to be included in the complex conception to which we give the specific name of man, as some of the greatest men that ever lived have been during parts of their lives deprived of the power of actual reasoning. This, however, it will be said, does not remove the difficulty; for the occasional exercise of reason in lunatics, and the great exertions of it in such men as Swift and Marlborough, show that they had it in capacity at all times; whereas we have no evidence that changelings have even a capacity of reasoning at any time, since they never do a rational action, nor ever utter a sentence to the purpose. That we have no direct and positive evidence of the minds of changelings being capable of reasoning, were they supplied with proper organs, must be granted; but the probabilities of their being so are many and great. We know by experience that the actual exercise of reason may be interrupted by an occasional and accidental pressure on the brain; and therefore we cannot doubt but that if this pressure were rendered permanent by any wrong configuration of the skull given to it in the womb, or in the act of being born into the world, an infant, with a mind capable of reasoning by means of proper organs, would by this accident be rendered, throughout the whole of life, an idiot or changeling. That idiotism is caused by such accidents, and is not the quality of an inferior mind occasionally given to a human body, will at∙least seem probable from the íòllowing considerations. ,

It does not appear that an animal body can live and move except whilst it is actuated by some mind. Whence, then, does the unborn infant derive its mind? It must be either immediately from God, or ex traduce from its parents; but if the mind of man be immaterial, it cannot be ex traduce. Now, as idiots are very few in number when compared with the rational part of the human species, and as God in the government of this world acts not by partial but by general laws, we must conclude that the law which he has established respecting the union of mind and matter is, that human bodies shall be animated with minds endowed with a capacity of reasoning, and that those who never exert this capacity are prevented by some such accident as we have assigned.