James Adam Commentary on Plato, Protagoras VIII.317B

But I do not conform to the method of all these persons, since I believe they did not accomplish any of their designs: for the purpose of all this disguise could not escape the able men of affairs in each city; the multitude, of course, perceive practically nothing, but merely echo this or that pronouncement of their leaders. Now to try to run away, and to fail through being caught in the act, 317b shows sad folly in the mere attempt, and must needs make people far more hostile; for they regard such an one, whatever else he may be, as a rogue. Hence the road I have taken is one entirely opposite to theirs: I admit that I am a sophist and that I educate men; and I consider this precaution, of admitting rather than denying, the better of the two. There are others besides that I have meditated, so as to avoid, under Heaven, 317c any harm that may come of admitting that I am a sophist. And yet many long years have I now been in the profession, for many in total number are those that I have lived: not one of you all, but in age I might be his father. ¹ Hence it suits me by far the best, in meeting your wishes, to make my discourse on these matters in the presence of all who are in the house.
  On this, as I suspected that he wished to make a display before Prodicus and Hippias, and give himself airs on the personal attachment shown by our coming to him, I remarked: 317d Then surely we must call Prodicus and Hippias and their followers to come and listen to us
  By all means, said Protagoras.
  Then do you agree, said Callias, to our making a session of it, so that we may sit at ease for our conversation?
  The proposal was accepted; and all of us, delighted at the prospect of listening to wise men, took hold of the benches and couches ourselves and arranged them where Hippias was, since the benches were there already. Meanwhile Callias and Alcibiades came, 317e bringing with them Prodicus, whom they had induced to rise from his couch, and Prodicus’ circle also.
  When we had all taken our seats,— So now, Socrates, said Protagoras, since these gentlemen are also present, be so good as to tell what you were mentioning to me a little while before on the young man’s behalf.