According to D.C. Schindler’s account ( Plato’s Critique of Impure Reason: On Goodness and Truth in the Republic , 42-3), Plato is not an idealist searching for a “pure” starting point. On the contrary, he knows that the search for such a standpoint is chimerical. The exploration of justice doesn’t start from a blank slate:

“As attempt follows attempt we eventually discover that such a fundamental question cannot be addressed without also addressing the more universal questions of what truth and goodness are, and these in turn require some apprehension of that which is ultimate in relation to all other things. In order to understand the initial question, then, we must already in some sense know what comes after it, and ultimately must know what comes last of all. In other words, we cannot truly begin until we have reached the end. Or as Plato puts it more commonly, all learning is a kind of recollection. The notion of a ‘pure’ or absolute beginning—which has been the aspiration in Enlightenment thought, German Idealism, and some forms of twentieth-century phenomenology—is foreign to Plato. Moving forward, for Plato, inevitably turns out to be in some respect a ‘catching up.’ When Socrates starts speaking in the opening scene of the dialogue, he reports something that occurred the previous day and in this report relates that he began already by coming from somewhere else: ‘I went down yesterday to the Piraeus.’ The natural question is: From where?”

But Socrates’s first line does signal something about where the dialogue is going. He is speaking about a trip from Athens to the port, but he uses kateben , a word heavy with philosophical and mystical weight:

one of its central philosophical themes, the ascent and descent through the levels of being and their corresponding powers of soul. And if we consider the Greek mythical world more broadly, this philosophical theme resonates within another, that of the hero’s (Odysseus, Heracles) journey to Hades and back. When Plato restarts the discussion in book II , the echo of the first beginning focuses more thematically the philosophical distinction that lies implicit already here: book II begins with Glaucon’s compelling Socrates to choose which he prefers, merely seeming ( dokein ) to persuade or truly ( alethos ) to do so (i.e., to choose between appearance and reality). If philosophy is, as Socrates will eventually say, an ‘ascent to what is’ (521c) or an ‘upward journey’ (517a) to reality beyond appearances, then the first beginning would seem to be an unphilosophical descent into appearances.”

This tells us something about Plato’s philosophical “method” and its “starting point”:

“It is . . . impossible to find a fully adequate beginning, because doing so would require already having reached the end. And yet one has to start somewhere. If we cannot explicitly presuppose the conclusion as already having been concluded, we ought to begin in a way that presupposes an openness to it. The best beginning would in this case be one that recognizes its inadequacy, or to put it in other terms, its relativity to a further end. But even here, a certain paradox remains, and must not be overlooked: if we as readers recognize that the beginning of the dialogue is relative and provisional, and that the questions it initially addresses will be revised within progressively developing contexts, it is only because we are already familiar with the dialogue as a whole and can anticipate where it is. If we did not know that there was any destination beyond the place at which the dialogue starts, we would strictly speaking be without means for perceiving its relativity. We could not, in other words, keep from making the beginning in a certain sense absolute and thereby from falsifying it.”

Dialogue acknowledges finitude, emphasizing the “situatedness, concreteness, particularity, and historicity” of the dialogue partners, and in this differs from “the omniscience and authority of a treatise of even epic narrative.” Schindler thinks, though, it is better to read Plato dramatically, since such a reading takes seriously the paradoxes of knowing wholes and parts: “To read the Republic dramatically, in this sense, would mean that we refuse to isolate the particular arguments or scenes as ‘hermeneutically sealed’ individual entities, and instead read them as dependent on what is to come, and thus in anticipation of the decisive reversal and the change it entails ‘from ignorance to knowledge.’ This change is the revelation of the idea of the good at the peak of the discussion. Regarding the present context, if we fail to see the incompleteness of the opening scene as intrinsic to its meaning, then we imprison ourselves within the relative part by making it, in spite of ourselves, a ne plus ultra . Plato returned over and over to rewrite the beginning of the Republic in order, we might say, to make it perfectly incomplete.”