Matter is something that supports modes. And is it not evident the thing supported is different from the thing supporting?

PHIL. So that something distinct from, and exclusive of, extension is supposed to be the SUBSTRATUM of extension?

HYL. Just so.

PHIL. Answer me, Hylas. Can a thing be spread without extension? or is not the idea of extension necessarily included in SPREADING?

HYL. It is.

PHIL. Whatsoever therefore you suppose spread under anything must have in itself an extension distinct from the extension of that thing under which it is spread?