PROPOSITION XXXVI.

Haecceity adds to the formal or specific and undetermined Nature some reality, by virtue of which such Nature is individuated, as exhibiting an incapacity of division into many of a character precisely similar to itself.

I. The first argument in proof of this Thesis is implicitly contained in the following observation of the Angelic Doctor. 'Wherever,' he remarks, 'there is found, in a multitude of Entities, anything common' (to them all), 'it behoves us to search for some principle of distinction.'^{1} For, if there were nothing in these entities but what is common to them all; they would be One, not many. There must, therefore, be something in each, which is not common to all, by virtue of which each is distinguished from its neighbour; and that something must be real, otherwise, the distinction would not be real. To put this argument in another form: The primary difference between that which is conceived by the human mind as a common or specific nature, and that same nature contracted to the Individual, consists in this; that the former has not, while the latter has, an incapacity of division into many of the same identical nature with itself. Now, incapacity of such division belongs intrinsically and of necessity to individual Being, wholly apart from, and independent of, human concept. James is himself and nobody else, not merely because we think him so; rather, we think him such, because such he really and truly is. Therefore, this negation of communicability must be founded in something positive, as all negation must be; and this something positive must be real, because the privation which constitutes Individual Unity is real.

II. This argument is confirmed by a sort of a posteriori proof, derived from daily experience. Take William and Henry, as representative of two men (we will say) personally known to us. They both have one common nature, otherwise we should not call them men; and that common nature distinguishes them from every other Species. They have, each of them, a soul united to, and informing, an organized body. In this they agree. But, so far, there is no apparent reason why William should be distinguished from Henry; nevertheless, we know full well that they are distinguished from each other, and that the distinction is not a creation of our own mind, but is something real and objective to us. Nay, what is more, we are able to discern certain points of difference, certain distinguishing characteristics, which mark off the one from the other; such as difference of height, build, feature, hair, disposition, habits, knowledge, virtue, and so on. Now, though these are the results, or the exhibition, of Haecceity rather than Haecceity itself; yet are they more than sufficient evidence that this individual difference is something real, which we might express by saying that William has this soul, Henry that, and that William has this particular body, Henry that. Consequently, the Haecceity in each is real, and constitutes the individuality of each under that essential or specific nature of humanity in which they are both one.

III. A third argument is drawn from an axiom, universally admitted by all Philosophers, properly so called, of whatever School, which declares that of singulars there is no science; because Science deals with universals, and with universals only. But, if there were no real addition made by Haecceity to the common or universal Nature, such a distinction would be superfluous; since really, (and in this way only, could either the one or the other be an object of Philosophy), the two would be identical.

IV. A similar argument is deducible from the nature of definitions. For all definitions, truly such, i.e. proper and essential definitions, are of common or specific Natures and not of individuals; which would imply, as in the preceding argument, that there is a real distinction between the two.

V. A fresh proof of the truth of the present Proposition is to be found in the distinction of properties belonging to men. For some there are, which belong to them as men, and are, therefore, common to them all. Such are, for instance, locomotion, sensile perception, speech, capability of laughter, and so forth. Others, again, there are which belong to some men and not to others, to one man and not to another. Thus, a talent for mimicry, an irascible temper, red hair, colour of the eyes, such or such stature and build, are evidently distinctive, not common; accidental, not essential. Hence, it has been justly observed, that the former class of properties belong to the individuals through the medium of their common Nature; whereas the latter class are predicable of the common or specific Nature, only through the medium of the Individual. Thus, William has the gift of speech, because he is a man; but men are red-haired only because Henry, Martha, &c., are red-haired; and a man is running, because James is running. But, if there be this real distinction of properties, as evidently there is, and some are direct and immediate attributes of the common or specific Nature, while the others are direct, and immediate attributes of the Individual, or individuals, as such; it follows that there must be a real distinction between them and, cousequently, that Haecceity or individual Unity makes some real addition to the specific Nature.

VI. A further proof, (and this shall be the last), is to be found in the relation of Haecceity to the specific Nature. Man -- to put the argument in the concrete -- is not essentially anything individual; if he were, his multiplication into many would be a sheer impossibility. On the contrary, he could not be conceived save as an individual; for we cannot form a true concept of a thing, which does not represent that which is of its essence. Yet there is no one who is not aware, that man is truly conceivable without any individual determination. If, then, man is not essentially individual; when he becomes individual, he must receive some addition which is outside the limits of his essence. Therefore, that addition must be something really distinct from man, considered simply as such. The consequence is sufficiently plain. For all will acknowledge that individual Being is something really existing in nature, and that we are supremely conscious of the fact ourselves. But this Haecceity is not essential to the specific Nature; nay, it is not essential even to the Individual himself, considered merely as a positive Entity. Therefore, some real addition must be made to the specific essence; for, that there is that which is essential and that which is not essential in a Being, necessarily involves a real distinction, nay, as it would seem, a real distinction of the most pronounced kind.

{1} 'In quibuscumque pluribus invenitur aliquid commune, oportet quaerere aliquid distinctivum.' 1ae xl, 2, c.