Theorem axfrege54a

Description: Justification for ax-frege54a . Identical to biid . (Contributed by RP, 24-Dec-2019)

	Ref	Expression
Assertion	axfrege54a	⊢ ( 𝜑 ↔ 𝜑 )

Proof

Step	Hyp	Ref	Expression
1		biid	⊢ ( 𝜑 ↔ 𝜑 )