Theorem ax1 1431

Description: Standard propositional axiom derived from Lukasiewicz axioms. (Contributed by NM, 22-Dec-2002.) (Proof modification is discouraged.) (New usage is discouraged.)

Assertion

Ref	Expression
ax1	⊢ (φ → (ψ → φ))

Proof of Theorem ax1

Step	Hyp	Ref	Expression
1		luklem5 1427	1 ⊢ (φ → (ψ → φ))

Syntax hints:   → wi 4

This theorem was proved from axioms:  ax-mp 5  ax-meredith 1406

This theorem is referenced by:  weds  5939