Book,  Chapter

1      I,  III  |       which we take to be the substratum, or support, of those ideas
2     II,  XXIII|     ourselves to suppose some substratum wherein they do subsist,
3     II,  XXIII|       knowing what it is) the substratum to those simple ideas we
4     II,  XXIII|      of what it is) to be the substratum to those operations we experiment
5     II,  XXIII|       a supposition of such a substratum as gives, as it were, a
6     II,  XXIII|     thus united in one common substratum, make up our complex ideas
7     II,  XXIII| united together in an unknown substratum: all which ideas are nothing
8     IV,  VI   |     to co-exist in an unknown substratum, which we call substance;