Russell in the History of Western Philosophy discusses the Sophists in the Chapter entitled ‘Protagoras’. He says that ‘Plato devoted himself to caricaturing and vilifying them’, but that ‘they must not be judged by his polemics.’ He characterizes the Sophists with the help of two passages from Plato’s dialogues: ‘In his lighter vein, take the following passage from the Euthydemus, in which two Sophists, Dionysodorus and Euthydemus, set to work to puzzle a simple-minded person named Ctesippus. Dionysodorus begins: “You say that you have a dog? – Yes, a villain of a one, said Ctesippus. – And he has puppies? – Yes, and they are very like himself.’ – And the dog is the father of them? – Yes, he said, I certainly saw him and the mother of the puppies come together. – And is he not yours? – To be sure he is. – Then he is a father, and he is yours; ergo, he is your father, and the puppies are your brothers.” In a more serious vein, take the dialogue called the Sophist … the only thing I want to mention … is the final conclusion: “The art of contradiction-making … that presents a shadow-play of words – such is the blood and lineage which can, with truth, be assigned to the authentic Sophist.”’
Russell maintains that what the Sophists ‘had to teach was not, in their minds, connected with religion or virtue. They taught the art of arguing, and as much knowledge as would help in this art.’
In the Euthydemus the two Sophists present themselves as follows: ‘The teaching of virtue is our principle occupation, and we believe that we can impart it better and quicker than any man.’ (273d8-9, tr. Jowett). In the Sophist the Eleatic Stranger defines the Sophist as ‘that sort, which professes to make acquaintances only for the sake of virtue, and demands a reward in the shape of money’ (223a3-4, tr. Jowett).
Protagoras says in Plato’s Protagoras: ‘I acknowledge that I am a sophist and educate men’ (homologȏ te sophistȇs einai kai paideuein anthrȏpous, 317b4-5) He tells Hippocrates who wants to becomes his disciple: ‘Young man, if you associate with me, on the very first day you will return home a better man than you came, and better on the second day than on the first, and better every day than you were on the day before.’ (318a6-9, tr. Jowett) When Socrates says that any teacher of any art could say the same, Protagoras specifies his art as follows: ‘If he comes to me, he will learn that which he comes to learn. And this is prudence in affairs private as well as public; he will learn to order his own house in the best manner, and he will be able to speak and act the best in the affairs of state.’ – Socrates: ‘Do I understand you, and is your meaning that you teach the art of politics, and that you promise to make men good citizens?’ – Protagoras: ‘That is exactly the profession which I make.’ (318e5-319a7, tr. Jowett)
Gorgias was an exception, to whom Russell’s characterization applies. Socrates asks Meno: ‘These Sophists (hoi sophistai soi houtoi) who are the only ones to profess [to teach virtue] (hoiper monoi epangellontai), do they seem to you to be teachers of virtue (dokousi didaskaloi einai aretȇs)?’ – Meno: ‘And this is what I admire most about Gorgias (Kai Gorgiou malista tauta agamai); you would never hear him promise this (hoti ouk an pote autou touto akousais hupischnoumenou), but he even laughs at those others (alla kai tȏn allȏn katagelai), when he hears that they promise it (hotan akousȇi hupischnoumenȏn); but he thinks that men should be taught to speak powerfully (alla legein oietai dein poiein deinous).’ (Pl. Meno 95b9-c4)