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Theorem mercolem1 1502
Description: Used to rederive the Tarski-Bernays-Wajsberg axioms from merco2 1501. (Contributed by Anthony Hart, 16-Aug-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
Assertion
Ref Expression
mercolem1 (((φψ) → χ) → (ψ → (θχ)))

Proof of Theorem mercolem1
StepHypRef Expression
1 merco2 1501 . 2 (((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ))))
2 merco2 1501 . . . 4 (((χφ) → (( ⊥ → φ) → (φψ))) → (((φψ) → χ) → (ψ → (θχ))))
3 merco2 1501 . . . . . . 7 (((ψ → (θχ)) → (( ⊥ → φ) → ⊥ )) → (( ⊥ → ψ) → (( ⊥ → φ) → (φψ))))
4 merco2 1501 . . . . . . 7 ((((ψ → (θχ)) → (( ⊥ → φ) → ⊥ )) → (( ⊥ → ψ) → (( ⊥ → φ) → (φψ)))) → (((( ⊥ → φ) → (φψ)) → (ψ → (θχ))) → (( ⊥ → φ) → (((φψ) → χ) → (ψ → (θχ))))))
53, 4ax-mp 5 . . . . . 6 (((( ⊥ → φ) → (φψ)) → (ψ → (θχ))) → (( ⊥ → φ) → (((φψ) → χ) → (ψ → (θχ)))))
6 merco2 1501 . . . . . 6 ((((( ⊥ → φ) → (φψ)) → (ψ → (θχ))) → (( ⊥ → φ) → (((φψ) → χ) → (ψ → (θχ))))) → (((((φψ) → χ) → (ψ → (θχ))) → (( ⊥ → φ) → (φψ))) → (( ⊥ → φ) → ((χφ) → (( ⊥ → φ) → (φψ))))))
75, 6ax-mp 5 . . . . 5 (((((φψ) → χ) → (ψ → (θχ))) → (( ⊥ → φ) → (φψ))) → (( ⊥ → φ) → ((χφ) → (( ⊥ → φ) → (φψ)))))
8 merco2 1501 . . . . 5 ((((((φψ) → χ) → (ψ → (θχ))) → (( ⊥ → φ) → (φψ))) → (( ⊥ → φ) → ((χφ) → (( ⊥ → φ) → (φψ))))) → ((((χφ) → (( ⊥ → φ) → (φψ))) → (((φψ) → χ) → (ψ → (θχ)))) → ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → (((φψ) → χ) → (ψ → (θχ)))))))
97, 8ax-mp 5 . . . 4 ((((χφ) → (( ⊥ → φ) → (φψ))) → (((φψ) → χ) → (ψ → (θχ)))) → ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → (((φψ) → χ) → (ψ → (θχ))))))
102, 9ax-mp 5 . . 3 ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → (((φψ) → χ) → (ψ → (θχ)))))
111, 10ax-mp 5 . 2 ((((φφ) → (( ⊥ → φ) → φ)) → ((φφ) → (φ → (φφ)))) → (((φψ) → χ) → (ψ → (θχ))))
121, 11ax-mp 5 1 (((φψ) → χ) → (ψ → (θχ)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wfal 1317
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 177  df-tru 1319  df-fal 1320
This theorem is referenced by:  mercolem4  1505  mercolem5  1506  mercolem6  1507  re1tbw2  1511
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