Metamath Proof Explorer


Theorem rsp2

Description: Restricted specialization, with two quantifiers. (Contributed by NM, 11-Feb-1997)

Ref Expression
Assertion rsp2 ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐵 𝜑 → ( ( 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) → 𝜑 ) )

Proof

Step Hyp Ref Expression
1 rsp ⊢ ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐵 𝜑 → ( 𝑥 ∈ 𝐴 → ∀ 𝑦 ∈ 𝐵 𝜑 ) )
2 rsp ⊢ ( ∀ 𝑦 ∈ 𝐵 𝜑 → ( 𝑦 ∈ 𝐵 → 𝜑 ) )
3 1 2 syl6 ⊢ ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐵 𝜑 → ( 𝑥 ∈ 𝐴 → ( 𝑦 ∈ 𝐵 → 𝜑 ) ) )
4 3 impd ⊢ ( ∀ 𝑥 ∈ 𝐴 ∀ 𝑦 ∈ 𝐵 𝜑 → ( ( 𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) → 𝜑 ) )