Modus Tollens
Natural & Formal Sciences Dictionary
Definition
A rule of inference: from 'If P then Q' (P → Q) and 'not Q' (¬Q), infer 'not P' (¬P). It is the standard way to reject antecedents via failure of consequents.
Modus Tollens
- Natural & Formal Sciences -
Mathematics & Logic Dictionary
Definition
A valid rule of inference that allows one to infer ¬A from premises A → B and ¬B; often stated as 'if A then B; not B; therefore not A.'