Seldom does Socrates meet his match when engaging in dialogue, but Protagoras is able to hold his own once he decides to engage Socrates rather than orate. This occurs following the encouragement of Alcibiades when they take up the question of virtue and its constituent parts (349b-354e).
When pressed by Socrates to admit that "the most confident are the most courageous" and thus that wisdom is courage, Protagoras makes a stand and reminds Socrates that "When I was asked if the courageous are confident, I agreed. I was not asked if the confident are courageous. If you had asked me that, I would have said, 'Not all of them.'" (350c) The typical word games that lead most of Socrates' interlocutors to their doom are not enough to trap Protagoras. Earlier in the dialogue Protagoras seems to view the event as a 'contest' and while Socrates does not share that view, it does seem that during this interchange it is a reasonable view that the participants are somewhat evenly matched.
Protagoras had previously briefly succeeded in persuading Socrates to engage in poetic interpretation (339a-349a). That attempt ended in a demonstration of the difficulties in determining the truth when the speaker (in this case the Poet) was not present. The return to the dialogue offered more success through engaging in the dialectical method. However, we still did not seem to be making much progress toward an answer to the question of whether virtue is teachable. ( )