Nicomachean Ethics

division, since philosophy properly taken, and its distribution, would seem to be considered on the part of those things which are, and not from the work of our intellect, nor on the part of those things which are made or done by us; yet for our present purpose we shall follow the division brought forward above, taking philosophy in a broad sense, and dividing it twofoldly into active philosophy and speculative, as we have said. And the sufficiency of this division seems to be derived from this, that our knowledge is either occupied with those things which are, or with those things which are done by us: the first knowledge constitutes the speculative part of philosophy, the second the active part. Furthermore, there is in us a twofold intellectual power, namely the speculative and the active, to which such a division of philosophy can rightly correspond and be accommodated, and it may not incongruously be said that the one is called active and the other speculative, as we have said. These, however, differ greatly among themselves, not only because of the diversity of the subjects with which they are concerned, but also because of their different ends and modes of proceeding. But each part of the brought-forward division must be taken and divided again into its members, so that they may become more clearly known. Since, therefore, philosophy has been distributed into the active and the speculative, the speculative
The division of speculative philosophy.

is again divided into three parts: into the natural, which is called physics; into the mathematical; and the metaphysical, which is also usually called first philosophy. And we can fittingly derive the sufficiency of this division from the distribution of the beings with which it is concerned. For those things which are, are divided into three kinds. For some beings are so deeply immersed in matter that they are not separated from it either according to being, or according to definition and formal reason; and these are said to be natural things, such as flesh, bone, gold, iron, and indeed the four elements, and all those things which consist of and are composed from them. Some, moreover, are entirely separate, and according to