Theorem issetiOLD

Description: Obsolete version of isseti as of 28-Aug-2023. A way to say " A is a set" (inference form). (Contributed by NM, 24-Jun-1993) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypothesis	isseti.1	$$⊢A\in \mathrm{V}$$
Assertion	issetiOLD	$$⊢\exists xx=A$$

Proof

Step	Hyp	Ref	Expression
1		isseti.1	$$⊢A\in \mathrm{V}$$
2		isset	$$⊢A\in \mathrm{V}\leftrightarrow \exists xx=A$$
3	1 2	mpbi	$$⊢\exists xx=A$$