Theorem hbn1 1889

Description: Alias for ax-10 1888 to be used instead of it. (Contributed by NM, 24-Jan-1993.) (Proof shortened by Wolf Lammen, 18-Aug-2014.)

Assertion

Ref	Expression
hbn1	|- ( -. A. x ph -> A. x -. A. x ph )

Proof of Theorem hbn1

Step	Hyp	Ref	Expression
1		ax-10 1888	1 |- ( -. A. x ph -> A. x -. A. x ph )

Syntax hints:   -. wn 3   -> wi 4   A.wal 1436

This theorem was proved from axioms:  ax-10 1888

This theorem is referenced by:  hbe1  1890  modal-5  1892  axc4  1912  axc7  1913  axc14  2167  ax12indn  32477  axc5c4c711  36654  vk15.4j  36787  ax6e2nd  36827  ax6e2ndVD  37210  ax6e2ndALT  37232