But that, in which that which is changed, is first changed, is necessarily an indivisible. But I call that first, which is not such from something else belonging to it being first: for let AC be divisible; and let it be divided in B. If, therefore, it is changed in AB, or again in B C, it will not be first changed in A C. But if it is changed in each (for it is necessary either that it should have been changed, or that it should change in each;) it will also be changed in the whole. But it was changed. The same reasoning applies if it changed in the one, but has been changed in the other: for there will be something prior to that which is first. So that the first in which that which is changed is changed, will not be divisible. It is evident, therefore, with respect to that which is corrupted, and that which is generated that the one is corrupted, and the other generated, in an indivisible.
