[50] Protagoras, son of Artemon or, according to Apollodorus and Dinon in the fifth book of his History of Persia, of Maeandrius, was born at Abdera (so says Heraclides of Pontus in his treatise On Laws, and also that he made laws for Thurii) or, according to Eupolis in his Flatterers, at Teos; for the latter says: He and Prodicus of Ceos gave public readings for which fees were charged, and Plato in the Protagoras ¹ calls Prodicus deep-voiced. Protagoras studied under Democritus. The latter ² was nicknamed Wisdom, according to Favorinus in his Miscellaneous History.

[51] Protagoras was the first to maintain that there are two sides to every question, opposed to each other, and he even argued in this fashion, being the first to do so. Furthermore he began a work thus: Man is the measure of all things, of things that are that they are, and of things that are not that they are not. He used to say that soul was nothing apart from the senses, as we learn from Plato in the Theaetetus, ³ and that everything is true. In another work he began thus: As to the gods, I have no means of knowing either that they exist or that they do not exist. For many are the obstacles that impede knowledge, both the obscurity of the question and the shortness of human life.

[52] For this introduction to his book the Athenians expelled him; and they burnt his works in the market-place, after sending round a herald to collect them from all who had copies in their possession.

He was the first to exact a fee of a hundred minae and the first to distinguish the tenses of verbs, to emphasize the importance of seizing the right moment, to institute contests in debating, and to teach rival pleaders the tricks of their trade. Furthermore, in his dialectic he neglected the meaning in favour of verbal quibbling, and he was the father of the whole tribe of eristical disputants now so much in evidence; insomuch that Timon ⁴ too speaks of him as ⁵

[53] He too first introduced the method of discussion which is called Socratic. Again, as we learn from Plato in the Euthydemus, ⁶ he was the first to use in discussion the argument of Antisthenes which strives to prove that contradiction is impossible, and the first to point out how to attack and refute any proposition laid down: so Artemidorus the dialectician in his treatise In Reply to Chrysippus. He too invented the shoulder-pad on which porters carry their burdens, so we are told by Aristotle in his treatise On Education; for he himself had been a porter, says Epicurus somewhere. ⁷ This was how he was taken up by Democritus, who saw how skilfully his bundles of wood were tied. He was the first to mark off the parts of discourse into four, namely, wish, question, answer, command ⁸ ;

[54] others divide into seven parts, narration, question, answer, command, rehearsal, wish, summoning; these he called the basic forms of speech. Alcidamas made discourse fourfold, affirmation, negation, question, address.

The first of his books he read in public was that On the Gods, the introduction to which we quoted above; he read it at Athens in Euripides’ house, or, as some say, in Megaclides’; others again make the place the Lyceum and the reader his disciple Archagoras, Theodotus’s son, who gave him the benefit of his voice. His accuser was Pythodorus, son of Polyzelus, one of the four hundred; Aristotle, however, says it was Euathlus.

[55] The works of his which survive are these: * * The Art of Controversy. Of Wrestling. On Mathematics. Of the State. Of Ambition. Of Virtues. Of the Ancient Order of Things. On the Dwellers in Hades. Of the Misdeeds of Mankind. A Book of Precepts. Of Forensic Speech for a Fee, two books of opposing arguments. This is the list of his works. ⁹ Moreover there is a dialogue which Plato wrote upon him.

Philochorus says that, when he was on a voyage to Sicily, his ship went down, and that Euripides hints at this in his Ixion.

[56] According to some his death occurred, when he was on a journey, at nearly ninety years of age, though Apollodorus makes his age seventy, assigns forty years for his career as a sophist, and puts his floruit in the 84th Olympiad. ¹⁰

There is an epigram of my own on him as follows ¹¹ :

The story is told that once, when he asked Euathlus his disciple for his fee, the latter replied, But I have not won a case yet. Nay, said Protagoras, if I win this case against you I must have the fee, for winning it; if you win, I must have it, because you win it.

There was another Protagoras, an astronomer, for whom Euphorion wrote a dirge; and a third who was a Stoic philosopher.