When we debate an issue with someone, we spontaneously offer reasons for one position or another, and we expect that these have some claim on the other person’s assent. If our reasons are strong, we generally assume that some assent is required, unless the person can produce stronger reasons for an alternative, which would then in turn obligate us. Such everyday situations raise fundamental philosophical questions: Why should reason have a claim on us, and if it does, what exactly is it that reason lays claim to in us? To what extent, and by what principle, does it bind? What...

The Republic begins (at least) twice; after the relatively independent and yet incomplete mini-dialogue of book I, book II starts with an explicit da capo. Even once the conversation is underway, restarts and revisions occur repeatedly.¹ The dialogue, it seems, runs into difficulty finding the right beginning, which is an unsettling difficulty if it is true that “the beginning is the most important part of every work” (337a). According to Socrates, “Everyone must therefore give great care to the beginning of any undertaking, to see whether his foundation is right or not.”² Ironically, it is reported that Plato repeatedly revised...

The Republic stands out among all of Plato’s dialogues, not merely because it seems to be the apex and flower of his mature period, not merely because it gathers together into a single dialogue many of the issues that appear separately in other works,¹ but also because it sets for itself the most ambitious epistemological project in the Platonic corpus: namely, to find an adequate way of distinguishing being from appearance. If we see the connection between this distinction and the corresponding distinctions between forms and images, knowledge and opinion, we will not have any trouble claiming that this distinction...

An image is volatile by nature. It is not simply a thing lying next to other things, because its own reality does not simply belong to it but lies in part elsewhere. We look through a photograph of a loved one as much as we look at it, in the sense that our attention moves to the person that we know and doesn’t come to a stop at the colored shapes on the surface. An image is in a decisive way what it is not. In this respect, we ought to think of an image not primarily as an object,...

“So I turned around, and Socrates was nowhere to be seen.”¹ Plato often refers to the realm of being, in contrast to the realm of becoming, as invisible, beyond manifestation to the physical senses.² At the same time, however, Plato will affirm that the higher realm of being is the one that is the brightest or most visible. The end of book V of the Republic contrasts being to becoming as the invisible to the visible (see 476a–b). But then the three analogies of books VI and VII all present the intelligible realm as superior to the sensible realm...

The Republic introduces the philosopher in the guise of a guardian. The beneficiary of this guardianship is, of course, the ideal city. But the philosopher’s task raises an immediate question: against whom does the philosopher guard the city? A “real” city must protect itself against its warring neighbors, but a “city-in-speech,” occupying “no place” (utopia), has no such neighbors. If we consider that a city in speech is in fact the rational ordering of a common life—the city is made, as Plato puts it, “from the beginning by reason” (τῷ λόγῳ ἐξ ἀϱχῆς ποιῶμον πόλιν, 369c)—then the most...

Raphael’s famous painting The School of Athens imaginatively illustrates a conventional belief regarding the two greatest Greek thinkers: Plato, the “idealist,” points upward to the heavens; Aristotle, the “realist,” gestures down toward the earth. Plato himself uses the directional metaphor to characterize the different relations to reality implied in the various μαϑήματα. According to this metaphor, philosophy is essentially an upward path. As the standard interpretation has it, to lead the soul upward, ἀνω, means to lead it away from the realm of becoming, which is in flux, to the realm of being, which remains eternally the same. The movement...