* Sophists went from town to town offering education for a fee. The curriculum varied (‘sophistry’ rarely implied any particular philosophical outlook), but was essentially about professional success; and as many preferments in Greek cities were by democratic election, oratory was in high demand. Some Sophists became very wealthy celebrities, and were accounted (or accounted themselves) the wise of Greek society. As for being ‘mercenary’, when the sophist Thrasymachus of Chalcedon (?459-?400 BC) joins the discussion with Socrates in Book I, Plato has him insist on payment before he will give his professional opinion on the nature of ‘justice’. Assured of his fee, he then blusters and sneers before offering this definition of justice: “In all States there is the same principle of justice, which is the interest of the government; and as the government must be supposed to have power, the only reasonable conclusion is that everywhere there is one principle of justice, which is the interest of the stronger.” One can see why he was in demand in government circles.

* An important qualification: the more unscrupulous of the Sophists were not mere populists, telling the public what they wanted to hear. They were skilled analysts, who had learnt to read and manipulate democratic assemblies in order to help fee-paying clients win the backing of voters and the patronage of the powerful. Right from the beginning, it would seem, the majority opinions and concerns of popular assemblies have been quite different from those of the public they reckon to represent.