Metamath Proof Explorer


Theorem rsp

Description: Restricted specialization. (Contributed by NM, 17-Oct-1996)

Ref Expression
Assertion rsp ⊢ ∀ x ∈ A φ → x ∈ A → φ

Proof

Step Hyp Ref Expression
1 df-ral ⊢ ∀ x ∈ A φ ↔ ∀ x x ∈ A → φ
2 sp ⊢ ∀ x x ∈ A → φ → x ∈ A → φ
3 1 2 sylbi ⊢ ∀ x ∈ A φ → x ∈ A → φ