Theorem bj-rspgt 15722

Description: Restricted specialization, generalized. Weakens a hypothesis of rspccv 2874 and seems to have a shorter proof. (Contributed by BJ, 21-Nov-2019.)

Hypotheses

Ref	Expression
bj-rspg.nfa	⊢ Ⅎ𝑥𝐴
bj-rspg.nfb	⊢ Ⅎ𝑥𝐵
bj-rspg.nf2	⊢ Ⅎ𝑥𝜓

Assertion

Ref	Expression
bj-rspgt	⊢ (∀𝑥(𝑥 = 𝐴 → (𝜑 → 𝜓)) → (∀𝑥 ∈ 𝐵 𝜑 → (𝐴 ∈ 𝐵 → 𝜓)))

Proof of Theorem bj-rspgt

Step	Hyp	Ref	Expression
1		eleq1 2268	. . . . . . . . 9 ⊢ (𝑥 = 𝐴 → (𝑥 ∈ 𝐵 ↔ 𝐴 ∈ 𝐵))
2	1	imbi1d 231	. . . . . . . 8 ⊢ (𝑥 = 𝐴 → ((𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) ↔ (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑))))
3	2	biimpd 144	. . . . . . 7 ⊢ (𝑥 = 𝐴 → ((𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑))))
4		imim2 55	. . . . . . . 8 ⊢ ((𝜑 → 𝜓) → ((∀𝑥 ∈ 𝐵 𝜑 → 𝜑) → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓)))
5	4	imim2d 54	. . . . . . 7 ⊢ ((𝜑 → 𝜓) → ((𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓))))
6	3, 5	syl9 72	. . . . . 6 ⊢ (𝑥 = 𝐴 → ((𝜑 → 𝜓) → ((𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓)))))
7	6	a2i 11	. . . . 5 ⊢ ((𝑥 = 𝐴 → (𝜑 → 𝜓)) → (𝑥 = 𝐴 → ((𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓)))))
8	7	alimi 1478	. . . 4 ⊢ (∀𝑥(𝑥 = 𝐴 → (𝜑 → 𝜓)) → ∀𝑥(𝑥 = 𝐴 → ((𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓)))))
9		bj-rspg.nfa	. . . . 5 ⊢ Ⅎ𝑥𝐴
10		bj-rspg.nfb	. . . . . . 7 ⊢ Ⅎ𝑥𝐵
11	9, 10	nfel 2357	. . . . . 6 ⊢ Ⅎ𝑥 𝐴 ∈ 𝐵
12		nfra1 2537	. . . . . . 7 ⊢ Ⅎ𝑥∀𝑥 ∈ 𝐵 𝜑
13		bj-rspg.nf2	. . . . . . 7 ⊢ Ⅎ𝑥𝜓
14	12, 13	nfim 1595	. . . . . 6 ⊢ Ⅎ𝑥(∀𝑥 ∈ 𝐵 𝜑 → 𝜓)
15	11, 14	nfim 1595	. . . . 5 ⊢ Ⅎ𝑥(𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓))
16		rsp 2553	. . . . . . 7 ⊢ (∀𝑥 ∈ 𝐵 𝜑 → (𝑥 ∈ 𝐵 → 𝜑))
17	16	a1i 9	. . . . . 6 ⊢ (𝑥 = 𝐴 → (∀𝑥 ∈ 𝐵 𝜑 → (𝑥 ∈ 𝐵 → 𝜑)))
18	17	com23 78	. . . . 5 ⊢ (𝑥 = 𝐴 → (𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)))
19	9, 15, 18	bj-vtoclgft 15711	. . . 4 ⊢ (∀𝑥(𝑥 = 𝐴 → ((𝑥 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜑)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓)))) → (𝐴 ∈ 𝐵 → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓))))
20	8, 19	syl 14	. . 3 ⊢ (∀𝑥(𝑥 = 𝐴 → (𝜑 → 𝜓)) → (𝐴 ∈ 𝐵 → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓))))
21	20	pm2.43d 50	. 2 ⊢ (∀𝑥(𝑥 = 𝐴 → (𝜑 → 𝜓)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜑 → 𝜓)))
22	21	com23 78	1 ⊢ (∀𝑥(𝑥 = 𝐴 → (𝜑 → 𝜓)) → (∀𝑥 ∈ 𝐵 𝜑 → (𝐴 ∈ 𝐵 → 𝜓)))

Syntax hints:   → wi 4  ∀wal 1371   = wceq 1373  Ⅎwnf 1483   ∈ wcel 2176  Ⅎwnfc 2335  ∀wral 2484

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-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-ext 2187

This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1484  df-sb 1786  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-ral 2489  df-v 2774

This theorem is referenced by:  bj-rspg  15723