Metamath Proof Explorer


Theorem axc11

Description: Show that ax-c11 can be derived from ax-c11n in the form of axc11n . Normally, axc11 should be used rather than ax-c11 , except by theorems specifically studying the latter's properties. Usage of this theorem is discouraged because it depends on ax-13 . Use the weaker axc11v when possible. (Contributed by NM, 16-May-2008) (Proof shortened by Wolf Lammen, 21-Apr-2018) (New usage is discouraged.)

Ref Expression
Assertion axc11
|- ( A. x x = y -> ( A. x ph -> A. y ph ) )

Proof

Step Hyp Ref Expression
1 axc11r
 |-  ( A. y y = x -> ( A. x ph -> A. y ph ) )
2 1 aecoms
 |-  ( A. x x = y -> ( A. x ph -> A. y ph ) )