MPE Home Metamath Proof Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >  pm2.01da Structured version   Visualization version   GIF version

Theorem pm2.01da 458
Description: Deduction based on reductio ad absurdum. (Contributed by Mario Carneiro, 9-Feb-2017.)
Hypothesis
Ref Expression
pm2.01da.1 ((𝜑𝜓) → ¬ 𝜓)
Assertion
Ref Expression
pm2.01da (𝜑 → ¬ 𝜓)

Proof of Theorem pm2.01da
StepHypRef Expression
1 pm2.01da.1 . . 3 ((𝜑𝜓) → ¬ 𝜓)
21ex 450 . 2 (𝜑 → (𝜓 → ¬ 𝜓))
32pm2.01d 181 1 (𝜑 → ¬ 𝜓)
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wa 384
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 197  df-an 386
This theorem is referenced by:  efrirr  5095  omlimcl  7658  hartogslem1  8447  cfslb2n  9090  fin23lem41  9174  tskuni  9605  4sqlem18  15666  ramlb  15723  ivthlem2  23221  ivthlem3  23222  cosne0  24276  footne  25615  nsnlplig  27333  unbdqndv1  32499  unbdqndv2  32502  knoppndv  32525  fmtno4prm  41487
  Copyright terms: Public domain W3C validator