Theorem bj-bijust0ALT 34736

Description: Alternate proof of bijust0 203; shorter but using additional intermediate results. (Contributed by NM, 11-May-1999.) (Proof shortened by Josh Purinton, 29-Dec-2000.) (Revised by BJ, 19-Mar-2020.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
bj-bijust0ALT	⊢ ¬ ((𝜑 → 𝜑) → ¬ (𝜑 → 𝜑))

Proof of Theorem bj-bijust0ALT

Step	Hyp	Ref	Expression
1		id 22	. 2 ⊢ (𝜑 → 𝜑)
2	1	bj-nimni 34724	1 ⊢ ¬ ((𝜑 → 𝜑) → ¬ (𝜑 → 𝜑))

Syntax hints:  ¬ wn 3   → wi 4

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem is referenced by: (None)