Theorem dfnan2 1489

Description: Alternative denial in terms of our primitive connectives (implication and negation). (Contributed by WL, 26-Jun-2020.)

Assertion

Ref	Expression
dfnan2	⊢ ((𝜑 ⊼ 𝜓) ↔ (𝜑 → ¬ 𝜓))

Proof of Theorem dfnan2

Step	Hyp	Ref	Expression
1		df-nan 1487	. 2 ⊢ ((𝜑 ⊼ 𝜓) ↔ ¬ (𝜑 ∧ 𝜓))
2		imnan 400	. 2 ⊢ ((𝜑 → ¬ 𝜓) ↔ ¬ (𝜑 ∧ 𝜓))
3	1, 2	bitr4i 277	1 ⊢ ((𝜑 ⊼ 𝜓) ↔ (𝜑 → ¬ 𝜓))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 205   ∧ wa 396   ⊼ wnan 1486

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 206  df-an 397  df-nan 1487

This theorem is referenced by:  nancom  1491  nannan  1492  nannot  1494  nanbi1  1496