“Meaning is exclusion” which means that “language can never point out anything specifically, only eliminate sets of possibilities (”possible worlds” for the modern philosopher or logician) from our consideration. That is, language - and therefore logic - can only say what isn’t the case. And that no matter how many possibilities were excluded by language, i.e., how specific our language, an infinite number would still remain (a now well-known property of infinite sets.) If, for example, we say that a friend of ours has red hair, someone listening to us knows that our friend doesn’t have black or light blonde colored hair, but not what precise shade, of all the infinite shades of red that are possible, their hair is. Nor do they know from what we’ve said how tall, or heavy, or witty our friend is. The possibilities are still infinite.”

This relates to some stuff I’ll put up here soon from Hallward’s book on Badiou. So far I’ve only read the intro and some of the appendix on intro to set theory. I’ve found the latter really helpful and interesting (perhaps in part because of my low level of literacy - numeracy? with formal systems).

See also “determination is negation” in Spinoza, Hegel, Marx at these links, respectively.

http://bdsweb.tripod.com/en/letters.htm
http://plato.stanford.edu/entries/hegel/
http://www.marxists.org/archive/marx/works/1857/grundrisse/intro-f.htm