Metamath Proof Explorer


Theorem newnod

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

Ref Expression
Hypothesis newnod.1 ⊢ φ → A ∈ N ⁡ B
Assertion newnod ⊢ φ → A ∈ No

Proof

Step Hyp Ref Expression
1 newnod.1 ⊢ φ → A ∈ N ⁡ B
2 newssno ⊢ N ⁡ B ⊆ No
3 2 1 sselid ⊢ φ → A ∈ No