Speech and Argument. People trying to convince others must always have used, however unconsciously, regular techniques of speech and argument. To that extent, rhetoric—the study of persuasive speaking—must far predate the earliest Greek texts. Yet, as a more formal discipline, with defined teachers and a consciously formulated body of knowledge to transmit, scholars can trace its beginnings to Sicily in the first half of the fifth century B.C.E. Aristotle tells us that, with the end of the tyrannies there at that time, and the subsequent rush of litigation in courts that were now free, the first teachers of rhetoric began to offer their services to citizens who wished to learn public speaking (by Greek law litigants were obliged to represent themselves in court). Aristotle actually regarded the philosopher Empedocles of Acragas as the founder of rhetoric, while other sources...