indirect proof
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In logic, an indirect proof, also known as a reductio ad absurdum, is a method of establishing the validity of a proposition. This type of proof involves assuming the contradictory of the conclusion and then demonstrating that this assumption leads to a contradiction, thereby proving the original proposition to be true. This contrasts with a direct proof, which establishes a conclusion through a series of logical steps without assuming the opposite.123
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syllogisticreduction and indirect reduction or reductio ad impossibile, Aristotle was able to reduce all syllogisms to those of the first figure. Today, in order to admit terms regardless of their emptiness or nonemptiness, syllogistic has become a special case of Boolean algebra in which the concepts of universal class and…
Read Morereduction and indirect reduction or reductio ad impossibile, Aristotle was able to reduce all syllogisms to those of the first figure. Today, in order to admit terms regardless of their emptiness or nonemptiness, syllogistic has become a special case of Boolean algebra in which the concepts of universal class and…
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history of logicSyllogismsReduction and indirect proof together suffice to prove all moods not in the first figure. This fact, which Aristotle himself showed, makes his syllogistic the first deductive system in the history of logic.
Read MoreReduction and indirect proof together suffice to prove all moods not in the first figure. This fact, which Aristotle himself showed, makes his syllogistic the first deductive system in the history of logic.
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