> It functions much like A e. _V would. A proof using this theorem can always > plug in _V for V but it also could plug in On, RR, or whatever is convenient. > Perhaps looking at <https://us.metamath.org/mpeuni/elex.html> makes it clear.
Okay, elements of ZF classes are always sets, so A e. V restricts A from being proper classes. That begs the question why one would ever use A e. _V though. Is this just a case where there's no particular convention? -- You received this message because you are subscribed to the Google Groups "Metamath" group. To unsubscribe from this group and stop receiving emails from it, send an email to metamath+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/metamath/272R9VKF3UZLE.34NMDVUCB3A1P%40wilsonb.com.