Metamath Proof Explorer


Theorem ralrid

Description: Sufficient condition for the restricted universal quantifier. Deduction form. (Contributed by Jonathan Ben-Naim, 3-Jun-2011)

Ref Expression
Hypothesis ralrid.1 φ x x A ψ
Assertion ralrid φ x A ψ

Proof

Step Hyp Ref Expression
1 ralrid.1 φ x x A ψ
2 df-ral x A ψ x x A ψ
3 1 2 sylibr φ x A ψ