Metamath Proof Explorer


Axiom ax-prv2

Description: Second property of three of the provability predicate. (Contributed by BJ, 3-Apr-2019)

Ref Expression
Assertion ax-prv2 ⊢ Prv φ → ψ → Prv φ → Prv ψ

Detailed syntax breakdown

Step Hyp Ref Expression
0 wph wff φ
1 wps wff ψ
2 0 1 wi wff φ → ψ
3 2 cprvb wff Prv φ → ψ
4 0 cprvb wff Prv φ
5 1 cprvb wff Prv ψ
6 4 5 wi wff Prv φ → Prv ψ
7 3 6 wi wff Prv φ → ψ → Prv φ → Prv ψ