Theorem bj-ralvw 37547

Description: A weak version of ralv 3484 not using ax-ext 2738 (nor df-cleq 2758, df-clel 2841, df-v 3460), and only core FOL axioms. See also bj-rexvw 37548. The analogues for reuv 3486 and rmov 3487 are not proved. (Contributed by BJ, 16-Jun-2019.) (Proof modification is discouraged.)

Hypothesis

Ref	Expression
bj-ralvw.1	⊢ 𝜓

Assertion

Ref	Expression
bj-ralvw	⊢ (∀𝑥 ∈ {𝑦 ∣ 𝜓}𝜑 ↔ ∀𝑥𝜑)

Proof of Theorem bj-ralvw

Step	Hyp	Ref	Expression
1		df-ral 3083	. 2 ⊢ (∀𝑥 ∈ {𝑦 ∣ 𝜓}𝜑 ↔ ∀𝑥(𝑥 ∈ {𝑦 ∣ 𝜓} → 𝜑))
2		bj-ralvw.1	. . . . 5 ⊢ 𝜓
3	2	vexw 2750	. . . 4 ⊢ 𝑥 ∈ {𝑦 ∣ 𝜓}
4	3	a1bi 365	. . 3 ⊢ (𝜑 ↔ (𝑥 ∈ {𝑦 ∣ 𝜓} → 𝜑))
5	4	albii 1852	. 2 ⊢ (∀𝑥𝜑 ↔ ∀𝑥(𝑥 ∈ {𝑦 ∣ 𝜓} → 𝜑))
6	1, 5	bitr4i 281	1 ⊢ (∀𝑥 ∈ {𝑦 ∣ 𝜓}𝜑 ↔ ∀𝑥𝜑)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209  ∀wal 1568   ∈ wcel 2146  {cab 2744  ∀wral 3082

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842

This proof depends on definitions:  df-bi 210  df-sb 2100  df-clab 2745  df-ral 3083

This theorem is used by: (None)