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 ( 𝜑𝜓 ) ) → ∀ 𝑥 ( 𝜑𝜓 ) )

Proof

Step Hyp Ref Expression
1 nfeu1 𝑥 ∃! 𝑥 𝜑
2 nfe1 𝑥𝑥 ( 𝜑𝜓 )
3 1 2 nfan 𝑥 ( ∃! 𝑥 𝜑 ∧ ∃ 𝑥 ( 𝜑𝜓 ) )
4 eupick ( ( ∃! 𝑥 𝜑 ∧ ∃ 𝑥 ( 𝜑𝜓 ) ) → ( 𝜑𝜓 ) )
5 3 4 alrimi ( ( ∃! 𝑥 𝜑 ∧ ∃ 𝑥 ( 𝜑𝜓 ) ) → ∀ 𝑥 ( 𝜑𝜓 ) )