Theorem rspcdf 3569

Description: Restricted specialization, using implicit substitution. (Contributed by Emmett Weisz, 16-Jan-2020.)

Hypotheses

Ref	Expression
rspcdf.1	⊢ Ⅎ𝑥𝜑
rspcdf.2	⊢ Ⅎ𝑥𝜒
rspcdf.3	⊢ (𝜑 → 𝐴 ∈ 𝐵)
rspcdf.4	⊢ ((𝜑 ∧ 𝑥 = 𝐴) → (𝜓 ↔ 𝜒))

Assertion

Ref	Expression
rspcdf	⊢ (𝜑 → (∀𝑥 ∈ 𝐵 𝜓 → 𝜒))

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Allowed substitution hints:   𝜑(𝑥)   𝜓(𝑥)   𝜒(𝑥)

Proof of Theorem rspcdf

Step	Hyp	Ref	Expression
1		rspcdf.1	. . 3 ⊢ Ⅎ𝑥𝜑
2		rspcdf.4	. . . 4 ⊢ ((𝜑 ∧ 𝑥 = 𝐴) → (𝜓 ↔ 𝜒))
3	2	ex 416	. . 3 ⊢ (𝜑 → (𝑥 = 𝐴 → (𝜓 ↔ 𝜒)))
4	1, 3	alrimi 2249	. 2 ⊢ (𝜑 → ∀𝑥(𝑥 = 𝐴 → (𝜓 ↔ 𝜒)))
5		rspcdf.3	. 2 ⊢ (𝜑 → 𝐴 ∈ 𝐵)
6		rspcdf.2	. . 3 ⊢ Ⅎ𝑥𝜒
7	6	rspct 3568	. 2 ⊢ (∀𝑥(𝑥 = 𝐴 → (𝜓 ↔ 𝜒)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜓 → 𝜒)))
8	4, 5, 7	sylc 65	1 ⊢ (𝜑 → (∀𝑥 ∈ 𝐵 𝜓 → 𝜒))

Syntax hints:   → wi 4   ↔ wb 208   ∧ wa 399  ∀wal 1559   = wceq 1561  Ⅎwnf 1804   ∈ wcel 2143  ∀wral 3077

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1816  ax-4 1830  ax-5 1931  ax-6 1988  ax-7 2029  ax-8 2145  ax-9 2153  ax-10 2176  ax-11 2192  ax-12 2213  ax-ext 2735

This theorem depends on definitions:  df-bi 209  df-an 400  df-or 859  df-ex 1801  df-nf 1805  df-cleq 2755  df-clel 2838  df-nfc 2912  df-ral 3078

This theorem is referenced by:  rspc2daf  32667