Theorem rspc2vd 3899

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 3887	. . 3 ⊢ (𝜑 → ⦋𝐴 / 𝑥⦌𝐷 = 𝐸)
5	1, 4	eleqtrrd 2867	. 2 ⊢ (𝜑 → 𝐵 ∈ ⦋𝐴 / 𝑥⦌𝐷)
6		nfcsb1v 3875	. . . . 5 ⊢ Ⅎ𝑥⦋𝐴 / 𝑥⦌𝐷
7		nfv 1949	. . . . 5 ⊢ Ⅎ𝑥𝜒
8	6, 7	nfralw 3313	. . . 4 ⊢ Ⅎ𝑥∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒
9		csbeq1a 3865	. . . . 5 ⊢ (𝑥 = 𝐴 → 𝐷 = ⦋𝐴 / 𝑥⦌𝐷)
10		rspc2vd.a	. . . . 5 ⊢ (𝑥 = 𝐴 → (𝜃 ↔ 𝜒))
11	9, 10	raleqbidv 3338	. . . 4 ⊢ (𝑥 = 𝐴 → (∀𝑦 ∈ 𝐷 𝜃 ↔ ∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒))
12	8, 11	rspc 3568	. . 3 ⊢ (𝐴 ∈ 𝐶 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → ∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒))
13	2, 12	syl 18	. 2 ⊢ (𝜑 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → ∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒))
14		rspc2vd.b	. . 3 ⊢ (𝑦 = 𝐵 → (𝜒 ↔ 𝜓))
15	14	rspcv 3576	. 2 ⊢ (𝐵 ∈ ⦋𝐴 / 𝑥⦌𝐷 → (∀𝑦 ∈ ⦋ 𝐴 / 𝑥⦌𝐷𝜒 → 𝜓))
16	5, 13, 15	sylsyld 62	1 ⊢ (𝜑 → (∀𝑥 ∈ 𝐶 ∀𝑦 ∈ 𝐷 𝜃 → 𝜓))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401   = wceq 1570   ∈ wcel 2147  ∀wral 3080  ⦋csb 3851

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1945  ax-6 2002  ax-7 2043  ax-8 2149  ax-9 2157  ax-10 2180  ax-11 2197  ax-12 2216  ax-ext 2735

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-tru 1573  df-ex 1813  df-nf 1817  df-sb 2102  df-clab 2742  df-cleq 2755  df-clel 2839  df-nfc 2913  df-ral 3081  df-sbc 3743  df-csb 3852

This theorem is used by:  insubm  19064  frcond1  30924  frgrwopreglem4a  30968  ismntd  33644  dfmgc2lem  33655  urpropd  33890  isthincd2lem1  50891