Metamath Proof Explorer


Theorem exse

Description: Any relation on a set is set-like on it. (Contributed by Mario Carneiro, 22-Jun-2015)

Ref Expression
Assertion exse ( 𝐴 ∈ 𝑉 → 𝑅 Se 𝐴 )

Proof

Step Hyp Ref Expression
1 rabexg ⊢ ( 𝐴 ∈ 𝑉 → { 𝑦 ∈ 𝐴 ∣ 𝑦 𝑅 𝑥 } ∈ V )
2 1 ralrimivw ⊢ ( 𝐴 ∈ 𝑉 → ∀ 𝑥 ∈ 𝐴 { 𝑦 ∈ 𝐴 ∣ 𝑦 𝑅 𝑥 } ∈ V )
3 df-se ⊢ ( 𝑅 Se 𝐴 ↔ ∀ 𝑥 ∈ 𝐴 { 𝑦 ∈ 𝐴 ∣ 𝑦 𝑅 𝑥 } ∈ V )
4 2 3 sylibr ⊢ ( 𝐴 ∈ 𝑉 → 𝑅 Se 𝐴 )