Metamath Proof Explorer


Theorem axc16i

Description: Inference with axc16 as its conclusion. (Contributed by NM, 20-May-2008) (Proof modification is discouraged.) Usage of this theorem is discouraged because it depends on ax-13 . Use axc16 instead. (New usage is discouraged.)

Ref Expression
Hypotheses axc16i.1
|- ( x = z -> ( ph <-> ps ) )
axc16i.2
|- ( ps -> A. x ps )
Assertion axc16i
|- ( A. x x = y -> ( ph -> A. x ph ) )

Proof

Step Hyp Ref Expression
1 axc16i.1
 |-  ( x = z -> ( ph <-> ps ) )
2 axc16i.2
 |-  ( ps -> A. x ps )
3 nfv
 |-  F/ z x = y
4 nfv
 |-  F/ x z = y
5 ax7
 |-  ( x = z -> ( x = y -> z = y ) )
6 3 4 5 cbv3
 |-  ( A. x x = y -> A. z z = y )
7 ax7
 |-  ( z = x -> ( z = y -> x = y ) )
8 7 spimvw
 |-  ( A. z z = y -> x = y )
9 equcomi
 |-  ( x = y -> y = x )
10 equcomi
 |-  ( z = y -> y = z )
11 ax7
 |-  ( y = z -> ( y = x -> z = x ) )
12 10 11 syl
 |-  ( z = y -> ( y = x -> z = x ) )
13 9 12 syl5com
 |-  ( x = y -> ( z = y -> z = x ) )
14 13 alimdv
 |-  ( x = y -> ( A. z z = y -> A. z z = x ) )
15 8 14 mpcom
 |-  ( A. z z = y -> A. z z = x )
16 equcomi
 |-  ( z = x -> x = z )
17 16 alimi
 |-  ( A. z z = x -> A. z x = z )
18 15 17 syl
 |-  ( A. z z = y -> A. z x = z )
19 1 biimpcd
 |-  ( ph -> ( x = z -> ps ) )
20 19 alimdv
 |-  ( ph -> ( A. z x = z -> A. z ps ) )
21 2 nf5i
 |-  F/ x ps
22 nfv
 |-  F/ z ph
23 1 biimprd
 |-  ( x = z -> ( ps -> ph ) )
24 16 23 syl
 |-  ( z = x -> ( ps -> ph ) )
25 21 22 24 cbv3
 |-  ( A. z ps -> A. x ph )
26 20 25 syl6com
 |-  ( A. z x = z -> ( ph -> A. x ph ) )
27 6 18 26 3syl
 |-  ( A. x x = y -> ( ph -> A. x ph ) )