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