Itinerant professional teachers in Greece, the Greek colonies in Sicily, and southern Italy in the 5th century bc. Sophists offered instruction in a wide range of subjects and skills considered necessary for public life, especially rhetoric, in return for fees. Gorgias of Leontini (c.483–376 bc) specialized in teaching rhetoric, and his visit to Athens in 427 bc encouraged the development of oratory there. Young Athenian democrats needed rhetoric to persuade the democratic assemblies. By questioning the nature of gods, conventions, and morals, and by their alleged ability to train men “to make the weaker argument the stronger” through rhetoric, they aroused some opposition. Their readiness to argue either cause in a dispute brought them condemnation from Plato as self-interested imitators of wisdom lacking any concern for the truth. However, the most renowned sophists, such as Gorgias and Protagoras (c.485–415 bc) drew relativist or sceptical conclusions from the defensibility of opposed claims, indicating a seriousness of purpose that Plato failed to acknowledge.

During the Roman empire sophists were essentially teachers of rhetoric. The word sophistry, meaning quibbling or fallacious reasoning, reflects both Plato’s view and the popular distrust of sophists.