Factive predicate
Factive predicate is a predicate which entails or presupposes the truth of one of its arguments.
Example
A sentence such as John knows that Bill is ill can be true only if its propositional argument Bill is ill is true. Factive predicates are distinguished from non-factive predicates (such as believe) and counter-factives (such as pretend). Thus, the truth-value of John believes that Bill is ill does not depend on the truth-value of the proposition Bill is ill, whereas John pretends that he is ill can only be true if he is not ill.
