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Theorem inegd 1362
Description: Negation introduction rule from natural deduction. (Contributed by Mario Carneiro, 9-Feb-2017.)
Hypothesis
Ref Expression
inegd.1 ((𝜑𝜓) → ⊥)
Assertion
Ref Expression
inegd (𝜑 → ¬ 𝜓)

Proof of Theorem inegd
StepHypRef Expression
1 inegd.1 . . 3 ((𝜑𝜓) → ⊥)
21ex 114 . 2 (𝜑 → (𝜓 → ⊥))
3 dfnot 1361 . 2 𝜓 ↔ (𝜓 → ⊥))
42, 3sylibr 133 1 (𝜑 → ¬ 𝜓)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wa 103  wfal 1348
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 604  ax-in2 605
This theorem depends on definitions:  df-bi 116  df-tru 1346  df-fal 1349
This theorem is referenced by:  genpdisj  7464  cauappcvgprlemdisj  7592  caucvgprlemdisj  7615  caucvgprprlemdisj  7643  suplocexprlemdisj  7661  suplocexprlemub  7664  suplocsrlem  7749  resqrexlemgt0  10962  resqrexlemoverl  10963  leabs  11016  climge0  11266  isprm5lem  12073  ennnfonelemex  12347  dedekindeu  13241  dedekindicclemicc  13250  pw1nct  13883
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