Theorem ral0OLD

Description: Obsolete version of ral0 as of 2-Sep-2024. (Contributed by NM, 20-Oct-2005) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Assertion	ral0OLD	$$⊢\forall x\in \varnothing \phi$$

Proof

Step	Hyp	Ref	Expression
1		noel	$$⊢\neg x\in \varnothing$$
2	1	pm2.21i	$$⊢x\in \varnothing \to \phi$$
3	2	rgen	$$⊢\forall x\in \varnothing \phi$$