What is rhetoric Rhetoric is one of the arts of using language as a means to persuade. Along with grammar and logic or dialectic,rhetoric is one of the three ancient arts of discourse. From ancient Greece to the late 19th Century,it was a central part of Western education,filling the need to train public speakers and writers to move audiences to action with arguments.What is rhetoric ? Rhetoric is one of the arts of using language as a means to persuade. Along with grammar and logic or dialectic, rhetoric is one of the three ancient arts of discourse. From ancient Greece to the late 19th Century, it was a central part of Western education, filling the need to train public speakers and writers to move audiences to action with arguments