Metamath Proof Explorer


Axiom ax-wl-11v

Description: Version of ax-11 with distinct variable conditions. Currently implemented as an axiom to detect unintended references to the foundational axiom ax-11 . It will later be converted into a theorem directly based on ax-11 . (Contributed by Wolf Lammen, 28-Jun-2019)

Ref Expression
Assertion ax-wl-11v x y φ y x φ

Detailed syntax breakdown

Step Hyp Ref Expression
0 vx setvar x
1 vy setvar y
2 wph wff φ
3 2 1 wal wff y φ
4 3 0 wal wff x y φ
5 2 0 wal wff x φ
6 5 1 wal wff y x φ
7 4 6 wi wff x y φ y x φ