4 ms·
Actually, I take back my statement that this is not set-theoretic union. If I'm willing to accept '(a a) as representing the set '(a) when I use it as an input
by paul_reiners 19y ago
Actually, I take back my statement that this is not set-theoretic union.
If I'm willing to accept '(a a) as representing the set '(a) when I use it as an input to union, I should be just as willing to accept '(a a b) as representing the set '(a b) when I receive it back from union.