Theorem vsnid

Description: A setvar variable is a member of its singleton. (Contributed by David A. Wheeler, 8-Dec-2018)

	Ref	Expression
Assertion	vsnid	$$⊢x\in \left\{x\right\}$$

Proof

Step	Hyp	Ref	Expression
1		vex	$$⊢x\in \mathrm{V}$$
2	1	snid	$$⊢x\in \left\{x\right\}$$