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Metamath Proof Explorer

Theorem nexfal

Description: There does not exist a set such that F. is true. (Contributed by Anthony Hart, 13-Sep-2011)

Ref Expression
Assertion nexfal ¬ ∃ 𝑥 ⊥

Proof

Step Hyp Ref Expression
1 fal ⊢ ¬ ⊥
2 1 nex ⊢ ¬ ∃ 𝑥 ⊥