Theorem leftno

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

	Ref	Expression
Assertion	leftno	$$⊢A\in L\left(B\right)\to A\in \mathrm{No}$$

Proof

Step	Hyp	Ref	Expression
1		leftssno	$$⊢L\left(B\right)\subseteq \mathrm{No}$$
2	1	sseli	$$⊢A\in L\left(B\right)\to A\in \mathrm{No}$$