ax-frege54a - Mathbox for Richard Penner

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Axiom ax-frege54a 43875

Description: Reflexive equality of wffs. The content of 𝜑 is identical with the content of 𝜑. Part of Axiom 54 of [Frege1879] p. 50. Identical to biid 261. (Contributed by RP, 24-Dec-2019.) (New usage is discouraged.)

**Assertion**
Ref	Expression
ax-frege54a	⊢ (𝜑 ↔ 𝜑)

**Detailed syntax breakdown of Axiom ax-frege54a**
Step	Hyp	Ref	Expression
1		wph	. 2 wff 𝜑
2	1, 1	wb 206	1 wff (𝜑 ↔ 𝜑)

Colors of variables: wff setvar class

This axiom is referenced by: frege54cor1a 43877

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