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Theorem e222 16526
Description: A virtual deduction elimination rule.
Hypotheses
Ref Expression
e222.1 |- . ph, ps   ⊢   ch .
e222.2 |- . ph, ps   ⊢   th .
e222.3 |- . ph, ps   ⊢   ta .
e222.4 |- (ch -> (th -> (ta -> et)))
Assertion
Ref Expression
e222 |- . ph, ps   ⊢   et .

Proof of Theorem e222
StepHypRef Expression
1 e222.1 . . . . . . . . . 10 |- . ph, ps   ⊢   ch .
21dfvd2i 16491 . . . . . . . . 9 |- (ph -> (ps -> ch))
32imp 377 . . . . . . . 8 |- ((ph /\ ps) -> ch)
4 e222.4 . . . . . . . 8 |- (ch -> (th -> (ta -> et)))
53, 4syl 12 . . . . . . 7 |- ((ph /\ ps) -> (th -> (ta -> et)))
6 e222.2 . . . . . . . . 9 |- . ph, ps   ⊢   th .
76dfvd2i 16491 . . . . . . . 8 |- (ph -> (ps -> th))
87imp 377 . . . . . . 7 |- ((ph /\ ps) -> th)
95, 8syl5 20 . . . . . 6 |- ((ph /\ ps) -> ((ph /\ ps) -> (ta -> et)))
109pm2.43i 78 . . . . 5 |- ((ph /\ ps) -> (ta -> et))
11 e222.3 . . . . . . 7 |- . ph, ps   ⊢   ta .
1211dfvd2i 16491 . . . . . 6 |- (ph -> (ps -> ta))
1312imp 377 . . . . 5 |- ((ph /\ ps) -> ta)
1410, 13syl5 20 . . . 4 |- ((ph /\ ps) -> ((ph /\ ps) -> et))
1514pm2.43i 78 . . 3 |- ((ph /\ ps) -> et)
1615ex 402 . 2 |- (ph -> (ps -> et))
1716dfvd2ir 16492 1 |- . ph, ps   ⊢   et .
Colors of variables: wff set class
Syntax hints:   -> wi 3   /\ wa 240   . vd2 16488
This theorem is referenced by:  e220 16527  e202 16529  e022 16531  e002 16533  e020 16535  e200 16537  e221 16539  e212 16541  e122 16543  e112 16544  e121 16546  e211 16547  e22 16561  suctrALT2VD 16660  en3lplem2VD 16668  19.21a3con13vVD 16676  tratrbVD 16685
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-vd2 16489
Copyright terms: Public domain