noun Logic.
- a reduction to an absurdity; the refutation of a proposition by demonstrating the inevitably absurd conclusion to which it would logically lead.
noun
- a method of disproving a proposition by showing that its inevitable consequences would be absurd
- a method of indirectly proving a proposition by assuming its negation to be true and showing that this leads to an absurdity
- application of a principle or proposed principle to an instance in which it is absurd
Latin, literally “reduction to the absurd.” Absurdum is neuter of absurdus. See reduction + absurd. The tactic is useful and unobjectionable in proofs in geometry.