Theorem 19.32r 1668

Description: One direction of Theorem 19.32 of [Margaris] p. 90. The converse holds if 𝜑 is decidable, as seen at 19.32dc 1667. (Contributed by Jim Kingdon, 28-Jul-2018.)

Hypothesis

Ref	Expression
19.32r.1	⊢ Ⅎ𝑥𝜑

Assertion

Ref	Expression
19.32r	⊢ ((𝜑 ∨ ∀𝑥𝜓) → ∀𝑥(𝜑 ∨ 𝜓))

Proof of Theorem 19.32r

Step	Hyp	Ref	Expression
1		19.32r.1	. . 3 ⊢ Ⅎ𝑥𝜑
2		orc 702	. . 3 ⊢ (𝜑 → (𝜑 ∨ 𝜓))
3	1, 2	alrimi 1510	. 2 ⊢ (𝜑 → ∀𝑥(𝜑 ∨ 𝜓))
4		olc 701	. . 3 ⊢ (𝜓 → (𝜑 ∨ 𝜓))
5	4	alimi 1443	. 2 ⊢ (∀𝑥𝜓 → ∀𝑥(𝜑 ∨ 𝜓))
6	3, 5	jaoi 706	1 ⊢ ((𝜑 ∨ ∀𝑥𝜓) → ∀𝑥(𝜑 ∨ 𝜓))

Syntax hints:   → wi 4   ∨ wo 698  ∀wal 1341  Ⅎwnf 1448

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-io 699  ax-5 1435  ax-gen 1437  ax-4 1498

This theorem depends on definitions:  df-bi 116  df-nf 1449

This theorem is referenced by:  19.31r  1669