Theorem hbnd 1669

Description: Deduction form of bound-variable hypothesis builder hbn 1668. (Contributed by NM, 3-Jan-2002.)

Hypotheses

Ref	Expression
hbnd.1	⊢ (𝜑 → ∀𝑥𝜑)
hbnd.2	⊢ (𝜑 → (𝜓 → ∀𝑥𝜓))

Assertion

Ref	Expression
hbnd	⊢ (𝜑 → (¬ 𝜓 → ∀𝑥 ¬ 𝜓))

Proof of Theorem hbnd

Step	Hyp	Ref	Expression
1		hbnd.1	. . 3 ⊢ (𝜑 → ∀𝑥𝜑)
2		hbnd.2	. . 3 ⊢ (𝜑 → (𝜓 → ∀𝑥𝜓))
3	1, 2	alrimih 1483	. 2 ⊢ (𝜑 → ∀𝑥(𝜓 → ∀𝑥𝜓))
4		hbnt 1667	. 2 ⊢ (∀𝑥(𝜓 → ∀𝑥𝜓) → (¬ 𝜓 → ∀𝑥 ¬ 𝜓))
5	3, 4	syl 14	1 ⊢ (𝜑 → (¬ 𝜓 → ∀𝑥 ¬ 𝜓))

Syntax hints:  ¬ wn 3   → wi 4  ∀wal 1362

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 615  ax-in2 616  ax-5 1461  ax-gen 1463  ax-ie2 1508  ax-4 1524  ax-ial 1548

This theorem depends on definitions:  df-bi 117  df-tru 1367  df-fal 1370

This theorem is referenced by: (None)