Documentary narration: a verb of active refutation, tracing its Latin origin as speaking against, and its distinctions from deny, refute, and gainsay.
Two British speakers on contradicting evidence versus contradicting a person, the difference between contradict, deny, and refute, and the peculiar problem of self-contradiction.
Instructor-led session: validation that detects contradictory form values, API middleware catching contradictory parameters, database constraints preventing contradictory states, UI contradiction warnings, and test suites that catch contradictory business logic.