Book 8
12
Also (d) just as a number does not admit of variation in degree, so neither does substance in the sense of form; if any substance does admit of this, it is substance in combination with matter.In Aristot. Categories 3b 33-4a 9 Aristotle does not allow this exception.
12
Let this suffice as a detailed account of the generation and destruction of so-called substances, in what sense they are possible and in what sense they are not; and of the reference of things to number.
1
As regards material substance, we must not fail to realize that even if all things are derived from the same primary cause, or from the same things as primary causesi.e. from prime matter or the four elements.; i.e. even if all things that are generated have the same matter for their first principle, nevertheless each thing has some matter peculiar to it; e.g., the sweet or the viscous is the proximate matter of mucus, and the bitter or some such thing is that of bile— although probably mucus and bile are derived from the same ultimate matter.
2
The result is that there is more than one matter of the same thing, when one thing is the matter of the other; e.g., mucus is derived from the viscous; and from the sweet, if the viscous is derived from the sweet; and from bile, by the analysis of bile into its ultimate matter. For there are two senses in which X comes from Y; either because X will be found further on than Y in the process of development, or because X is produced when Y is analyzed into its original constituents.
3
And different things can be generated by the moving cause when the matter is one and the same, e.g. a chest and a bed from wood. But some different things must necessarily have different matter; e.g., a saw cannot be generated from wood, nor does this lie in the power of the moving cause, for it cannot make a saw of wool or wood.
