This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.

Metamath Proof Explorer


Theorem hbn1

Description: Alias for ax-10 to be used instead of it. (Contributed by NM, 24-Jan-1993) (Proof shortened by Wolf Lammen, 18-Aug-2014)

Ref Expression
Assertion hbn1 ¬ x φ x ¬ x φ

Proof

Step Hyp Ref Expression
1 ax-10 ¬ x φ x ¬ x φ