THE SUBSTRATE IS NOT A QUALITY COMMON TO ALL ELEMENTS; FOR THUS IT WOULD NOT BE INDETERMINATE.
13. Those who insist that the substrate of things is a quality common to all elements are bound to explain first the nature of this quality; then, how a quality could serve as substrate; how an unextended, immaterial (?) quality could be perceived in something that lacked extension; further, how, if this quality be determinate, it can be matter; for if it be something indeterminate, it is no longer a quality, but matter itself that we seek.