Meditations, Book 12, Section 23

Marcus Aurelius — The Emperor

There is only one sun, even though walls and mountains and countless other things block its light. There is only one substance that makes up the whole world, even though it gets shaped into endless different bodies. There is only one universal soul, even though it gets divided into countless individual spirits. The same goes for one universal mind, even though it seems split apart. All the other parts we've talked about — like animal souls or physical objects — don't naturally connect to each other, even when they have some kind of intelligence guiding them. But every rational mind has this special quality: it reaches out to other rational minds like itself and wants to join with them. This deep connection between thinking beings cannot be blocked or divided or limited the way other universal things can be.

Marcus Aurelius — The Emperor Original

There is but one light of the sun, though it be intercepted by walls and mountains, and other thousand objects. There is but one common substance of the whole world, though it be concluded and restrained into several different bodies, in number infinite. There is but one common soul, though divided into innumerable particular essences and natures. So is there but one common intellectual soul, though it seem to be divided. And as for all other parts of those generals which we have mentioned, as either sensitive souls or subjects, these of themselves (as naturally irrational) have no common mutual reference one unto another, though many of them contain a mind, or reasonable faculty in them, whereby they are ruled and governed. But of every reasonable mind, this the particular nature, that it hath reference to whatsoever is of her own kind, and desireth to be united: neither can this common affection, or mutual unity and correspondency, be here intercepted or divided, or confined to particulars as those other common things are.