Rhetoric (from Greek ρήτωρ, rhêtôr, "orator") is the art or technique of persuasion, usually through the use of language. Rhetoric is one of the three original liberal arts or trivium (the other members are dialectic and grammar) in Western culture. In ancient and medieval times, grammar concerned itself with correct language use through the study and criticism of literary models, dialectic concerned itself with the testing and invention of new knowledge through a process of question and answer, and rhetoric concerned itself with persuasion in public and political settings such as assemblies and courts of law.