Metamath Proof Explorer


Theorem bnj1247

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

Ref Expression
Hypothesis bnj1247.1 ( 𝜑 ↔ ( 𝜓𝜒𝜃𝜏 ) )
Assertion bnj1247 ( 𝜑𝜃 )

Proof

Step Hyp Ref Expression
1 bnj1247.1 ( 𝜑 ↔ ( 𝜓𝜒𝜃𝜏 ) )
2 id ( 𝜃𝜃 )
3 1 2 bnj771 ( 𝜑𝜃 )