Metamath Proof Explorer


Theorem bj-nnf-cbvali

Description: Compared with bj-nnf-cbvaliv , replacing the DV condition on y , ps with the nonfreeness condition requires ax-11 . (Contributed by BJ, 4-Apr-2026)

Ref Expression
Hypotheses bj-nnf-cbvali.nf0 ( 𝜑 → ∀ 𝑥 𝜑 )
bj-nnf-cbvali.nf1 ( 𝜑 → ∀ 𝑦 𝜑 )
bj-nnf-cbvali.ps ( 𝜑 → Ⅎ' 𝑦 𝜓 )
bj-nnf-cbvali.ch ( 𝜑 → Ⅎ' 𝑥 𝜒 )
bj-nnf-cbvali.is ( ( 𝜑𝑥 = 𝑦 ) → ( 𝜓𝜒 ) )
Assertion bj-nnf-cbvali ( 𝜑 → ( ∀ 𝑥 𝜓 → ∀ 𝑦 𝜒 ) )

Proof

Step Hyp Ref Expression
1 bj-nnf-cbvali.nf0 ( 𝜑 → ∀ 𝑥 𝜑 )
2 bj-nnf-cbvali.nf1 ( 𝜑 → ∀ 𝑦 𝜑 )
3 bj-nnf-cbvali.ps ( 𝜑 → Ⅎ' 𝑦 𝜓 )
4 bj-nnf-cbvali.ch ( 𝜑 → Ⅎ' 𝑥 𝜒 )
5 bj-nnf-cbvali.is ( ( 𝜑𝑥 = 𝑦 ) → ( 𝜓𝜒 ) )
6 3 bj-nnfad ( 𝜑 → ( 𝜓 → ∀ 𝑦 𝜓 ) )
7 1 6 hbald ( 𝜑 → ( ∀ 𝑥 𝜓 → ∀ 𝑦𝑥 𝜓 ) )
8 1 4 5 bj-nnf-spim ( 𝜑 → ( ∀ 𝑥 𝜓𝜒 ) )
9 2 7 8 bj-alrimd ( 𝜑 → ( ∀ 𝑥 𝜓 → ∀ 𝑦 𝜒 ) )