Kitap 9
4
But things are not all said to exist actually in the same sense, but only by analogy—as A is in B or to B, so is C in or to D; for the relation is either that of motion to potentiality, or that of substance to some particular matter.
5
Infinity and void and other concepts of this kind are said to be potentially or actually in a different sense from the majority of existing things, e.g. that which sees, or walks, or is seen.
6
For in these latter cases the predication may sometimes be truly made without qualification, since that which is seen is so called sometimes because it is seen and sometimes because it is capable of being seen; but the Infinite does not exist potentially in the sense that it will ever exist separately in actuality; it is separable only in knowledge. For the fact that the process of division never ceases makes this actuality exist potentially, but not separately.For Aristotle’s views about infinity and void see Aristot. Physics 3.4-8, 4.6-9 respectively.
7
Since no action which has a limit is an end, but only a means to the end, as, e.g., the process of thinning; and since the parts of the body themselves, when one is thinning them, are in motion in the sense that they are not already that which it is the object of the motion to make them, this process is not an action, or at least not a complete one, since it is not an end; it is the process which includes the end that is an action.
8
E.g., at the same time we see and have seen, understand and have understood, think and have thought; but we cannot at the same time learn and have learnt, or become healthy and be healthy. We are living well and have lived well, we are happy and have been happy, at the same time; otherwise the process would have had to cease at some time, like the thinning-process; but it has not ceased at the present moment; we both are living and have lived.
8
Now of these processes we should call the one type motions, and the other actualizations.
