Metamath Proof Explorer


Theorem leftnod

Description: An element of a left set is a surreal. (Contributed by Scott Fenton, 27-Feb-2026)

Ref Expression
Hypothesis leftel.1 ⊢ φ → A ∈ L ⁡ B
Assertion leftnod ⊢ φ → A ∈ No

Proof

Step Hyp Ref Expression
1 leftel.1 ⊢ φ → A ∈ L ⁡ B
2 leftno ⊢ A ∈ L ⁡ B → A ∈ No
3 1 2 syl ⊢ φ → A ∈ No