Metamath Proof Explorer


Theorem eupicka

Description: Version of eupick with closed formulas. (Contributed by NM, 6-Sep-2008)

Ref Expression
Assertion eupicka ∃!xφxφψxφψ

Proof

Step Hyp Ref Expression
1 nfeu1 x∃!xφ
2 nfe1 xxφψ
3 1 2 nfan x∃!xφxφψ
4 eupick ∃!xφxφψφψ
5 3 4 alrimi ∃!xφxφψxφψ