Once more Adeimantus returns with the allusion to his brother Glaucon whom he compares to the contentious State; in the next book he is again superseded, and Glaucon continues to the end.
Thus in a succession of characters Plato represents the successive stages of morality, beginning with the Athenian gentleman of the olden time, who is followed by the practical man of that day regulating his life by proverbs and saws; to him succeeds the wild generalization of the Sophists, and lastly come the young disciples of the great teacher, who know the sophistical arguments but will not be convinced by them, and desire to go deeper into the nature of things.

These too, like Cephalus, Polemarchus, Thrasymachus, are clearly distinguished from one another.

Neither in the Republic, nor in any other Dialogue of Plato, is a single character repeated.
The delineation of Socrates in the Republic is not wholly consistent.

In the first book we have more of the real Socrates, such as he is depicted in the Memorabilia of Xenophon, in the earliest Dialogues of Plato, and in the Apology.

He is ironical, provoking, questioning, the old enemy of the Sophists, ready to put on the mask of Silenus as well as to argue seriously.