Metamath Proof Explorer


Theorem rspcdv

Description: Restricted specialization, using implicit substitution. (Contributed by NM, 17-Feb-2007) (Revised by Mario Carneiro, 4-Jan-2017)

Ref Expression
Hypotheses rspcdv.1 φ A B
rspcdv.2 φ x = A ψ χ
Assertion rspcdv φ x B ψ χ

Proof

Step Hyp Ref Expression
1 rspcdv.1 φ A B
2 rspcdv.2 φ x = A ψ χ
3 2 biimpd φ x = A ψ χ
4 1 3 rspcimdv φ x B ψ χ