Theorem rspcdf 3547

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 413	. . 3 ⊢ (𝜑 → (𝑥 = 𝐴 → (𝜓 ↔ 𝜒)))
4	1, 3	alrimi 2225	. 2 ⊢ (𝜑 → ∀𝑥(𝑥 = 𝐴 → (𝜓 ↔ 𝜒)))
5		rspcdf.3	. 2 ⊢ (𝜑 → 𝐴 ∈ 𝐵)
6		rspcdf.2	. . 3 ⊢ Ⅎ𝑥𝜒
7	6	rspct 3546	. 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 207   ∧ wa 396  ∀wal 1545   = wceq 1547  Ⅎwnf 1790   ∈ wcel 2119  ∀wral 3053

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1802  ax-4 1816  ax-5 1917  ax-6 1974  ax-7 2015  ax-8 2121  ax-9 2129  ax-10 2152  ax-11 2168  ax-12 2189  ax-ext 2711

This theorem depends on definitions:  df-bi 208  df-an 397  df-or 854  df-ex 1787  df-nf 1791  df-cleq 2731  df-clel 2814  df-nfc 2888  df-ral 3054

This theorem is referenced by:  rspc2daf  32553