="Dan Asimov" <dasimov@earthlink.net> I believe that quite commonly in mathematical logic, exactly what Mike said is typically used without the periods:
∀x ∃y P(x, y) or ∀x ∃y ∋
P(x,y)
to mean "For all x there exists a y such that P(x,y)" --Dan OK so in the first example here the "such that" is simply implicit and in the second it is explicitly written as "backwards member-of". I personally like either of those for this purpose. But from this discussion I'm getting uncomfortable with vertical bar; this isn't a set comprehension so much as a logical statement. And while the colon is ASCII friendly, I'd rather not overload ordinary text punctuation marks with technical interpretations if possible. Does anyone think that either nothing or "nolispe" would be an awful choice?