Metamath Proof Explorer


Theorem rgen

Description: Generalization rule for restricted quantification. (Contributed by NM, 19-Nov-1994)

Ref Expression
Hypothesis rgen.1 ( 𝑥𝐴𝜑 )
Assertion rgen 𝑥𝐴 𝜑

Proof

Step Hyp Ref Expression
1 rgen.1 ( 𝑥𝐴𝜑 )
2 df-ral ( ∀ 𝑥𝐴 𝜑 ↔ ∀ 𝑥 ( 𝑥𝐴𝜑 ) )
3 2 1 mpgbir 𝑥𝐴 𝜑