Theorem rspcdf 3570

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 418	. . 3 ⊢ (𝜑 → (𝑥 = 𝐴 → (𝜓 ↔ 𝜒)))
4	1, 3	alrimi 2252	. 2 ⊢ (𝜑 → ∀𝑥(𝑥 = 𝐴 → (𝜓 ↔ 𝜒)))
5		rspcdf.3	. 2 ⊢ (𝜑 → 𝐴 ∈ 𝐵)
6		rspcdf.2	. . 3 ⊢ Ⅎ𝑥𝜒
7	6	rspct 3569	. 2 ⊢ (∀𝑥(𝑥 = 𝐴 → (𝜓 ↔ 𝜒)) → (𝐴 ∈ 𝐵 → (∀𝑥 ∈ 𝐵 𝜓 → 𝜒)))
8	4, 5, 7	sylc 66	1 ⊢ (𝜑 → (∀𝑥 ∈ 𝐵 𝜓 → 𝜒))

This proof depends on syntax axioms:   → wi 4   ↔ wb 209   ∧ wa 401  ∀wal 1568   = wceq 1570  Ⅎwnf 1816   ∈ wcel 2146  ∀wral 3081

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 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-10 2179  ax-11 2195  ax-12 2216  ax-ext 2737

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-ex 1813  df-nf 1817  df-cleq 2757  df-clel 2840  df-nfc 2914  df-ral 3082

This theorem is used by:  rspc2daf  32886