Axiom ax-7d 2295

Description: Distinct variable version of ax-7 1734. (Contributed by Mario Carneiro, 14-Aug-2015.)

Assertion

Ref	Expression
ax-7d	|- (A.xA.yph -> A.yA.xph)

Distinct variable group:   x,y

Allowed substitution hints:   ph(x,y)

Detailed syntax breakdown of Axiom ax-7d

Step	Hyp	Ref	Expression
1		wph	. . . 4 wff ph
2		vy	. . . 4 setvar y
3	1, 2	wal 1540	. . 3 wff A.yph
4		vx	. . 3 setvar x
5	3, 4	wal 1540	. 2 wff A.xA.yph
6	1, 4	wal 1540	. . 3 wff A.xph
7	6, 2	wal 1540	. 2 wff A.yA.xph
8	5, 7	wi 4	1 wff (A.xA.yph -> A.yA.xph)

This axiom is referenced by: (None)