One could say that what differentiates ancient from modern philosophy is the fact that, in ancient philosophy, it was not only Chrysippus or Epicurus who, just because they had developed a philosophical discourse, were considered philosophers. Rather, every person who lived according to the precepts of Chrysippus or Epicurus was every bit as much a philosopher as they.
Pierre HadotThere was a Socratic style of life (which the Cynics were to imitate), and the Socratic dialogue was an exercise which brought Socrates' interlocutor to put himself in question, to take care of himself, and to make his soul as beautiful and wise as possible.
Pierre HadotOnly he who is capable of a genuine encounter with the other is capable of an authentic encounter with himself, and the converse is equally true...From this perspective, every spiritual exercise is a dialogue, insofar as it is an exercise of authentic presence, to oneself and to others.
Pierre HadotSocrates splits himself into two, so that there are two Socrates: the Socrates who knows in advance how the discussion is going to end, and the Socrates who travels the entire dialectical path along with his interlocutor.
Pierre Hadot