Metamath Proof Explorer


Theorem eupicka

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

Ref Expression
Assertion eupicka ⊢ ∃! x φ ∧ ∃ x φ ∧ ψ → ∀ x φ → ψ

Proof

Step Hyp Ref Expression
1 nfeu1 ⊢ Ⅎ x ∃! x φ
2 nfe1 ⊢ Ⅎ x ∃ x φ ∧ ψ
3 1 2 nfan ⊢ Ⅎ x ∃! x φ ∧ ∃ x φ ∧ ψ
4 eupick ⊢ ∃! x φ ∧ ∃ x φ ∧ ψ → φ → ψ
5 3 4 alrimi ⊢ ∃! x φ ∧ ∃ x φ ∧ ψ → ∀ x φ → ψ