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{%type%} Definitions

WordNet 3.0Copyright Princeton University
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Short "hint"

(Logic) A form of inference in which a negative proposition is obtained from an affirmative, or vice versa

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Usage examples (7)
  • A similar thing happened with the principle of obversion.
  • These are the theory of the syllogism and the doctrines of contraposition and obversion.
  • Take any universal affirmative proposition; convert it by obversion
  • Thus, by obversion, each of the four propositions retains its quantity but changes its quality: A. to E.,
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