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Theorem waj-ax 14238
Description: A single axiom for propositional calculus offered by Wajsberg.
Assertion
Ref Expression
waj-ax |- ((ph -/\ (ps -/\ ch)) -/\ (((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))) -/\ (ph -/\ (ph -/\ ps))))

Proof of Theorem waj-ax
StepHypRef Expression
1 nic-justlem 1231 . . 3 |- ((ph -/\ (ps -/\ ch)) <-> (ph -> (ps /\ ch)))
2 pm2.27 76 . . . . . . . . . 10 |- (ph -> ((ph -> ch) -> ch))
32anim2d 620 . . . . . . . . 9 |- (ph -> ((th /\ (ph -> ch)) -> (th /\ ch)))
43expdimp 406 . . . . . . . 8 |- ((ph /\ th) -> ((ph -> ch) -> (th /\ ch)))
5 simpr 350 . . . . . . . . 9 |- ((ps /\ ch) -> ch)
65imim2i 11 . . . . . . . 8 |- ((ph -> (ps /\ ch)) -> (ph -> ch))
74, 6syl5com 63 . . . . . . 7 |- ((ph -> (ps /\ ch)) -> ((ph /\ th) -> (th /\ ch)))
87con3d 111 . . . . . 6 |- ((ph -> (ps /\ ch)) -> (-. (th /\ ch) -> -. (ph /\ th)))
9 df-nand 1230 . . . . . 6 |- ((th -/\ ch) <-> -. (th /\ ch))
10 df-nand 1230 . . . . . 6 |- ((ph -/\ th) <-> -. (ph /\ th))
118, 9, 103imtr4g 612 . . . . 5 |- ((ph -> (ps /\ ch)) -> ((th -/\ ch) -> (ph -/\ th)))
12 nic-justim 1232 . . . . 5 |- (((th -/\ ch) -> (ph -/\ th)) <-> ((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))))
1311, 12sylib 215 . . . 4 |- ((ph -> (ps /\ ch)) -> ((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))))
14 pm3.21 306 . . . . . . . 8 |- (ps -> (ph -> (ph /\ ps)))
1514adantr 425 . . . . . . 7 |- ((ps /\ ch) -> (ph -> (ph /\ ps)))
1615com12 14 . . . . . 6 |- (ph -> ((ps /\ ch) -> (ph /\ ps)))
1716a2i 10 . . . . 5 |- ((ph -> (ps /\ ch)) -> (ph -> (ph /\ ps)))
18 nic-justlem 1231 . . . . 5 |- ((ph -/\ (ph -/\ ps)) <-> (ph -> (ph /\ ps)))
1917, 18sylibr 217 . . . 4 |- ((ph -> (ps /\ ch)) -> (ph -/\ (ph -/\ ps)))
2013, 19jca 310 . . 3 |- ((ph -> (ps /\ ch)) -> (((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))) /\ (ph -/\ (ph -/\ ps))))
211, 20sylbi 216 . 2 |- ((ph -/\ (ps -/\ ch)) -> (((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))) /\ (ph -/\ (ph -/\ ps))))
22 nic-justlem 1231 . 2 |- (((ph -/\ (ps -/\ ch)) -/\ (((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))) -/\ (ph -/\ (ph -/\ ps)))) <-> ((ph -/\ (ps -/\ ch)) -> (((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))) /\ (ph -/\ (ph -/\ ps)))))
2321, 22mpbir 207 1 |- ((ph -/\ (ps -/\ ch)) -/\ (((th -/\ ch) -/\ ((ph -/\ th) -/\ (ph -/\ th))) -/\ (ph -/\ (ph -/\ ps))))
Colors of variables: wff set class
Syntax hints:  -. wn 2   -> wi 3   /\ wa 240   -/\ wnand 1229
This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7
This theorem depends on definitions:  df-bi 164  df-an 242  df-nand 1230
Copyright terms: Public domain