quantity is always called a part of it, e.g. two is called in a sense a part of three. — (2) It means, of the parts in the first sense, only those which measure the whole; this is why two, though in one sense it is, in another is not, a part of three. — (3) The elements into which the kind might be divided apart from the quantity, are also called parts of it; for which reason we say the species are parts of the genus. — (4) The elements into which the whole is divided, or of which it consists — 'the whole' meaning either the form or that which has the form; e.g. of the bronze sphere or of the bronze cube both the bronze — i.e. the matter in which the form is — and the characteristic angle are parts. — (5) The elements in the formula which explains a thing are parts of the whole; this is why the genus is called a part of the species, though in another sense the species is part of the genus.
Chapter 26
'A whole' means (1) that from which is absent none of the parts of which it is said to be naturally a whole, and (2) that which so contains the things it contains that they form a unity; and this in two senses — either as each and all one, or as making up the unity between them. For (a) that which is true of a whole class and is said to hold good as a whole (which implies that it is a kind of whole) is true of a whole in the sense that it contains many things by being predicated of each, and that each and all of them, e.g. man, horse, god, are one, because all are living things. But (b) the continuous and limited is a whole, when there is a unity consisting of several parts present in it, especially if they are present only potentially,[1] but, failing this, even if they are present actually. Of these things themselves, those which are so by nature are wholes in a higher degree than those which are so by art, as we said[2] in the case of unity also, wholeness being in fact a sort of oneness.
Again, as quantities have a beginning and a middle and an end, those to which the position does not make a difference are called totals, and those to which it does, wholes, and those
