contradiction
Argument Clinic – Monty Python sketch, a Monty Python sketch in which one of the two disputants repeatedly uses only contradictions in his argument Dialetheism — View that there exists statements which are both true and false Doublethink – Simultaneously accepting two mutually contradictory beliefs as correct Irony – Rhetorical device, literary technique, or situation in which there is an incongruity between the literal and the implied meaning Oxymoron – rhetorical device that uses an ostensible self-contradiction to illustrate a rhetorical point or to reveal a paradox Paradox – Statement that apparently contradicts itself Tautology – Logical formula which is true in every possible interpretation