Theorem pm2.43d 50

Description: Deduction absorbing redundant antecedent. (Contributed by NM, 18-Aug-1993.) (Proof shortened by O'Cat, 28-Nov-2008.)

Hypothesis

Ref	Expression
pm2.43d.1	|- ( ph -> ( ps -> ( ps -> ch ) ) )

Assertion

Ref	Expression
pm2.43d	|- ( ph -> ( ps -> ch ) )

Proof of Theorem pm2.43d

Step	Hyp	Ref	Expression
1		id 19	. 2 |- ( ps -> ps )
2		pm2.43d.1	. 2 |- ( ph -> ( ps -> ( ps -> ch ) ) )
3	1, 2	mpdi 43	1 |- ( ph -> ( ps -> ch ) )

Syntax hints:   -> wi 4

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7

This theorem is referenced by:  loolin  102  pm2.18dc  862  sbcof2  1858  rgen2a  2586  rspct  2903  po2nr  4406  ordsuc  4661  funssres  5369  2elresin  5443  f1imass  5914  smoel  6465  tfri3  6532  nnmass  6654  sbthlem1  7155  genpcdl  7738  genpcuu  7739  recexprlemss1l  7854  recexprlemss1u  7855  grpid  13621  uniopn  14724  elabgft1  16374  bj-rspgt  16382