Kitap 13
1
We have already explained what the substance of sensible things is, dealing in our treatise on physicsThe reference is presumably to Aristot. Physics 1. with the material substrate, and subsequently with substance as actuality.In Books 7-9.
2
Now since we are inquiring whether there is or is not some immutable and eternal substance besides sensible substances, and if there is, what it is, we must first examine the statements of other thinkers, so that if they have been mistaken in any respect, we may not be liable to the same mistakes; and if there is any view which is common to them and us, we may not feel any private self-irritation on this score. For we must be content if we state some points better than they have done, and others no worse.
3
There are two views on this subject. Some say that mathematical objects, i.e. numbers and lines, are substances; and others again that the Ideas are substances.
