Metamath Proof Explorer


Theorem ax7v1

Description: First of two weakened versions of ax7v , with an extra disjoint variable condition on x , z , see comments there. (Contributed by BJ, 7-Dec-2020)

Ref Expression
Assertion ax7v1
|- ( x = y -> ( x = z -> y = z ) )

Proof

Step Hyp Ref Expression
1 ax7v
 |-  ( x = y -> ( x = z -> y = z ) )