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Theorem nanim 1292
Description: Show equivalence between implication and the Nicod version. To derive nic-dfim 1434, apply nanbi 1294. (Contributed by Jeff Hoffman, 19-Nov-2007.)
Assertion
Ref Expression
nanim ⊢ ((φ → ψ) ↔ (φ ⊼ (ψ ⊼ ψ)))

Proof of Theorem nanim
StepHypRef Expression
1 nannan 1291 . 2 ⊢ ((φ ⊼ (ψ ⊼ ψ)) ↔ (φ → (ψ ∧ ψ)))
2 anidmdbi 627 . 2 ⊢ ((φ → (ψ ∧ ψ)) ↔ (φ → ψ))
31, 2bitr2i 241 1 ⊢ ((φ → ψ) ↔ (φ ⊼ (ψ ⊼ ψ)))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4   ↔ wb 176   ∧ wa 358   ⊼ wnan 1287
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This proof depends on definitions:  df-bi 177  df-an 360  df-nan 1288
This theorem is used by:  nic-dfim  1434  nic-ax  1438
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