Theorem rspc2vd 3927

Description: Deduction version of 2-variable restricted specialization, using implicit substitution. Notice that the class 𝐷 for the second set variable 𝑦 may depend on the first set variable 𝑥. (Contributed by AV, 29-Mar-2021.)

Hypotheses

Ref	Expression
rspc2vd.a	⊢ (𝑥 = 𝐴 → (𝜃 ↔ 𝜒))
rspc2vd.b	⊢ (𝑦 = 𝐵 → (𝜒 ↔ 𝜓))
rspc2vd.c	⊢ (𝜑 → 𝐴 ∈ 𝐶)
rspc2vd.d	⊢ ((𝜑 ∧ 𝑥 = 𝐴) → 𝐷 = 𝐸)
rspc2vd.e	⊢ (𝜑 → 𝐵 ∈ 𝐸)

Assertion

Ref	Expression
rspc2vd	⊢ (𝜑 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → 𝜓))

Distinct variable groups:   𝑥,𝐴,𝑦   𝑦,𝐵   𝑥,𝐶   𝑦,𝐷   𝑥,𝐸   𝜑,𝑥   𝜒,𝑥   𝜓,𝑦

Allowed substitution hints:   𝜑(𝑦)   𝜓(𝑥)   𝜒(𝑦)   𝜃(𝑥,𝑦)   𝐵(𝑥)   𝐶(𝑦)   𝐷(𝑥)   𝐸(𝑦)

Proof of Theorem rspc2vd

Step	Hyp	Ref	Expression
1		rspc2vd.e	. . 3 ⊢ (𝜑 → 𝐵 ∈ 𝐸)
2		rspc2vd.c	. . . 4 ⊢ (𝜑 → 𝐴 ∈ 𝐶)
3		rspc2vd.d	. . . 4 ⊢ ((𝜑 ∧ 𝑥 = 𝐴) → 𝐷 = 𝐸)
4	2, 3	csbied 3915	. . 3 ⊢ (𝜑 → ⦋𝐴 / 𝑥⦌𝐷 = 𝐸)
5	1, 4	eleqtrrd 2838	. 2 ⊢ (𝜑 → 𝐵 ∈ ⦋𝐴 / 𝑥⦌𝐷)
6		nfcsb1v 3903	. . . . 5 ⊢ Ⅎ𝑥⦋𝐴 / 𝑥⦌𝐷
7		nfv 1914	. . . . 5 ⊢ Ⅎ𝑥𝜒
8	6, 7	nfralw 3295	. . . 4 ⊢ Ⅎ𝑥∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒
9		csbeq1a 3893	. . . . 5 ⊢ (𝑥 = 𝐴 → 𝐷 = ⦋𝐴 / 𝑥⦌𝐷)
10		rspc2vd.a	. . . . 5 ⊢ (𝑥 = 𝐴 → (𝜃 ↔ 𝜒))
11	9, 10	raleqbidv 3329	. . . 4 ⊢ (𝑥 = 𝐴 → (∀𝑦 ∈ 𝐷 𝜃 ↔ ∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒))
12	8, 11	rspc 3594	. . 3 ⊢ (𝐴 ∈ 𝐶 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → ∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒))
13	2, 12	syl 17	. 2 ⊢ (𝜑 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → ∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒))
14		rspc2vd.b	. . 3 ⊢ (𝑦 = 𝐵 → (𝜒 ↔ 𝜓))
15	14	rspcv 3602	. 2 ⊢ (𝐵 ∈ ⦋𝐴 / 𝑥⦌𝐷 → (∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒 → 𝜓))
16	5, 13, 15	sylsyld 61	1 ⊢ (𝜑 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → 𝜓))

Syntax hints:   → wi 4   ↔ wb 206   ∧ wa 395   = wceq 1540   ∈ wcel 2109  ∀wral 3052  ⦋csb 3879

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2008  ax-8 2111  ax-9 2119  ax-10 2142  ax-11 2158  ax-12 2178  ax-ext 2708

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1543  df-ex 1780  df-nf 1784  df-sb 2066  df-clab 2715  df-cleq 2728  df-clel 2810  df-nfc 2886  df-ral 3053  df-sbc 3771  df-csb 3880

This theorem is referenced by:  insubm  18801  frcond1  30252  frgrwopreglem4a  30296  ismntd  32969  dfmgc2lem  32980  urpropd  33232  isthincd2lem1  49278