Metamath Proof Explorer


Theorem stcltrlem2

Description: Lemma for strong classical state theorem. (Contributed by NM, 24-Oct-1999) (New usage is discouraged.)

Ref Expression
Hypotheses stcltr1.1 φ S States x C y C S x = 1 S y = 1 x y
stcltr1.2 A C
stcltrlem1.3 B C
Assertion stcltrlem2 φ B A A B

Proof

Step Hyp Ref Expression
1 stcltr1.1 φ S States x C y C S x = 1 S y = 1 x y
2 stcltr1.2 A C
3 stcltrlem1.3 B C
4 1 2 3 stcltrlem1 φ S B = 1 S A A B = 1
5 2 choccli A C
6 2 3 chincli A B C
7 5 6 chjcli A A B C
8 1 3 7 stcltr1i φ S B = 1 S A A B = 1 B A A B
9 4 8 mpd φ B A A B