Theorem wl-dfclel.just

Description: Add a hypotheses to wl-dfclel.basic , that allows alpha-renaming. (Contributed by Wolf Lammen, 7-Apr-2026)

	Ref	Expression
Hypothesis	wl-dfclel.just.1	|- ( E. x ( x = A /\ x e. B ) <-> E. y ( y = A /\ y e. B ) )
Assertion	wl-dfclel.just	|- ( A e. B <-> E. x ( x = A /\ x e. B ) )

Proof

Step	Hyp	Ref	Expression
1		wl-dfclel.just.1	|- ( E. x ( x = A /\ x e. B ) <-> E. y ( y = A /\ y e. B ) )
2		wl-dfclel.basic	|- ( A e. B <-> E. x ( x = A /\ x e. B ) )