Book 3
4
Thus if this is necessarily so, it is necessary for this reason to posit the Forms also. For even if their exponents do not articulate their theory properly, still this is what they are trying to express, and it must be that they maintain the Forms on the ground that each of them is a substance, and none of them exists by accident.
5
On the other hand, if we are to assume that the Forms exist, and that the first principles are one in number but not in kind, we have already statedAristot. Met. 3.4.9, 10. the impossible consequences which must follow.This problem is not stated in ch. 1., but is akin to problems 5. and 8., which see.
5
(12.) Closely connected with these questions is the problem whether the elements exist potentially or in some other sense.
6
If in some other sense, there will be something else prior to the first principles. For the potentiality is prior to the actual cause, and the potential need not necessarily always become actual. On the other hand, if the elements exist potentially, it is possible for nothing to exist; for even that which does not yet exist is capable of existing. That which does not exist may come to be, but nothing which cannot exist comes to be.For the relation of potentiality to actuality see Aristot. Met. 9.1-9. The second point raised in this connection in ch. 1 is not discussed here; for actuality and motion see Aristot. Met. 12.6, 7.
