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Theorem ax11v 1263
Description: This is a version of ax-11o 1216 when the variables are distinct. Axiom (C8) of [Monk2] p. 105. See theorem ax11v2 1213 for the rederivation of ax-11o 1216 from this theorem.
Assertion
Ref Expression
ax11v |- (x = y -> (ph -> A.x(x = y -> ph)))
Distinct variable group:   x,y

Proof of Theorem ax11v
StepHypRef Expression
1 ax-16 1208 . . . 4 |- (A.x x = y -> ((x = y -> ph) -> A.x(x = y -> ph)))
2 ax-1 4 . . . 4 |- (ph -> (x = y -> ph))
31, 2syl5 21 . . 3 |- (A.x x = y -> (ph -> A.x(x = y -> ph)))
43a1d 12 . 2 |- (A.x x = y -> (x = y -> (ph -> A.x(x = y -> ph))))
5 ax-11o 1216 . 2 |- (-. A.x x = y -> (x = y -> (ph -> A.x(x = y -> ph))))
64, 5pm2.61i 126 1 |- (x = y -> (ph -> A.x(x = y -> ph)))
Colors of variables: wff set class
Syntax hints:   -> wi 3  A.wal 952   = wceq 954
This theorem is referenced by:  sb56 1264
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7  ax-16 1208  ax-11o 1216
Copyright terms: Public domain