Introduction

Theaetetus offers his third and final definition: knowledge is true opinion plus a logos. So understood, knowledge, as a whole, is complex. Insofar as its diverse components' contributions are not simply redundant, knowledge cannot merely be a sum of its parts. It must also possess some unifying principle. The precise meanings of both its parts and this unifying principle are in question. Knowledge itself as an object of knowledge possesses the character evident in every other object of knowledge. So too does every effort to know exhibit the difficulties attendant on knowing in general. The present effort, which takes knowledge as its object, is no exception. The intensely reflexive character of the dialogue reaches a peak in this final definition.

Socrates characterizes Theaetetus' opinion about the meaning of knowledge as a dream. Its dream-like haziness summons the analysis, the logos, that occupies much of the forthcoming discussion. In this analysis, the interlocutors aim to grasp that principle by virtue of which knowledge is a whole, not only as a matter of opinion but also in truth. Now, at the end, Socrates maintains, and Theaetetus agrees, that they remain in aporia regarding knowledge. But through this investigation the contours of the aporia become evident. Their investigation does reveal that the objects of knowledge are necessarily complex unities, always both many and one. Moreover, these objects are as such necessarily available to us in diverse ways, just as the distinction between true opinion and logos suggests.

Introduction

Socrates' ad hominem challenge to Protagoras confronts this central contradiction in the sophist's thought: the egalitarianism of Protagoras' doctrine is at odds with the inegalitarian implication of his own expertise. Through this confrontation, which moves the argument toward the dialogue's central passage, Socrates shows that Protagoras' theory, his view of the character of knowledge, is instrumental to his notion of good. Protagoras expresses this notion in a particular understanding of advantage, of what's “good for” oneself. The heart of the dialogue faces the question as to whether Protagoras and his adherents, Theodorus and Theaetetus, have rightly understood human good. In particular, it explores whether advantage understood in Protagorean terms can be the good for him, or for any of us, insofar as we are beings capable of self-contradiction, beings whose heterogeneous nature generates such conflicts as that regarding equality, which are inherent in political life.

The “delivery” already made evident the connection between one's view of good, on the one hand, and what knowledge is taken to be, on the other. This connection makes the adequacy of Protagoras' understanding of good bear on the explicit theme of the dialogue. Doubts about the adequacy of that understanding raise the question as to whether, like Protagoras, we should regard the knowledge we seek as the most certain means to a universally accepted good.

Introduction

My interpretation of Plato's Theaetetus aims to give full weight to the political substance of the dialogue. Readers will be excused for thinking this aim should have produced a work considerably shorter than the one they now hold in their hands. It assuredly is not due to its political insight that the Theaetetus ranks among the most studied of Plato's dialogues. The dialogue earns that privileged place because of its penetrating examination of no less a question than what is the meaning of knowledge. In the rarefied atmosphere of such a question my consideration of the dialogue's political teaching may seem an unwelcome, because unwise, lowering of our sights. But I do not recommend that we look at politics instead of knowledge. Rather, I hope to show that Plato's treatment of the Theaetetus' pervasive theme can only be properly understood through careful attention to the dialogue's political character. To begin to establish the plausibility of my thesis I want to sketch the more prominent political features of the Theaetetus. I start with the dialogue's conclusion because it locates the Theaetetus as a whole in an eminently political context.

At the dialogue's end, Socrates makes this portentous announcement: “But now there's something I need to go and face in the courtyard of the king-archon, in response to the indictment which Meletus has drawn up against me (210d2–4).” With Socrates' walk to the courtyard he begins his inexorable march to death in an Athenian cell.

Introduction

How a work begins – its title, first words, and opening passages – are often taken to be particularly clear indications of an author's intent. The material an author places at the beginning occurs before a plot or an argument exerts constraints. It is reasonable to believe, therefore, that with this greater latitude the author speaks more directly to us, in a manner more reflective of his or her choice. Because of his authorial anonymity such signs are especially valuable to Plato's readers. In these choices the veil of anonymity is for a moment less opaque, affording a glimpse of Plato's authorial hand.

A particular feature of the Theaetetus reinforces this need to fix our attention on the dialogue's opening passages. Throughout the dialogue Socrates insists that Theaetetus must reexamine the beginning of the argument in recognition of the extent to which the starting point of reflection shapes all that follows. As active readers of the dialogue we appropriately apply Socrates’ advice to the dialogue in which it occurs.

Heeding this advice, we must pay careful attention to the dialogue's Prologue. Such care is not misplaced. For the remarkable Prologue with which Plato begins the Theaetetus does shape in discernible ways the subsequent conversation between Socrates and the mathematicians.

Plato uses the device of a prologue in other dialogues, but the Theaetetus' Prologue is distinctive in several respects. The scholarly reaction to it helps us appreciate its unusual character.

Introduction

The Digression begins with Theodorus reminding Socrates that they are at leisure, to which Socrates replies, “we appear to be (172c3, emphasis added).” Socrates knows he is on the threshold of a very unleisurely epoch in his life. At the center of the upcoming turmoil, and of this dialogue, is the conflict between the philosophic and political lives that Socrates now explores. His examination of this issue elaborates, in particular, on those necessities of political life that intrude on the Theodoran hope for a life of leisurely freedom. We have already seen Theodorus' desire to be free of those harsh necessities, but it intensifies in the Digression (172e2, d1–2, d4, d5, d8, e1–5, 173a4–5, 173b6). Fueling this hope, a hope evident also in Protagoras' outlook, is the possibility that speech can secure one's freedom from these necessities, that it can provide the leisure to do whatever one pleases.

Much to Theodorus' delight, Socrates does juxtapose the freely flying Philosophers to the slavish participants in political life. Socrates' exaltation of the philosophic life enflames Theodorus' desire to such a degree that he envisions on the horizon the possibility that Socrates' speech could bring about “more peace and fewer evils among human beings (176a3–4).” Yet, just as this reign of perpetual peace is about to dawn, Socrates brings Theodorus smack against a most profound necessity. Evil, Socrates asserts, is a necessary concomitant of good and, as such, can never perish. Evil is ineradicable.

Introduction

Of the three definitions of knowledge in the Theaetetus, the first examined in detail – that knowledge is perception – occupies fully half of the dialogue. Preceding this definition is a discussion between Theodorus and Socrates, and eventually including Theaetetus, the pervasive theme of which is teaching and learning. The discussion culminates in Socrates' introduction of the midwife image to describe his characteristic activity. The image aims, most obviously, to encourage Theaetetus in his attempts to say what knowledge is. It succeeds, inducing Theaetetus to offer the definition that “knowledge is nothing else than perception (151e2–3).” Any assessment of this definition and its vital role in the dialogue requires an examination of the vivid, not to say outlandish, image that prompts its generation.

However, something more than the image's rhetorical effectiveness links the midwife image and Theaetetus' definition. There is a deep substantive relationship between the image and the definition, albeit an antithetical one. Following the exposition of the definition, Socrates explicitly opposes the two, maintaining that if Theaetetus' definition is correct then his own philosophic activity must be rejected as “nonsense” (161e7–162a2). Specifically subject to this verdict is his midwifery, his teaching through “conversation” that seeks “to examine and try to refute the appearances and opinions of one another (161e5, e6, e7–8).” Socrates thus makes the midwife image the bearer of his flag in a contest whose outcome may entail the wholesale rejection of his philosophy.

Introduction

Socrates' exhortations in the midwife passage succeed to this extent: Theaetetus is moved to offer a definition of knowledge. “Knowledge,” he maintains, “is nothing else than perception (151e2–3).” Fully one-half the dialogue's length is devoted to the formulation and examination, the delivery and assessment, of this psychic offspring. In many ways, Plato raises the suspicion that considerations beyond the initial definition's intrinsic validity dictate this lengthy treatment. The most prominent such suggestion is that it is Socrates who gives Theaetetus' offspring its ultimate form. Through Socrates' exertions, Theaetetus' initial, ambiguous definition develops into nothing less than a comprehensive view of humanity and the whole.

Socrates' guiding hand is evident not only in this magnification of the original thesis but also in its radicalization, by which I mean its thoroughgoing sub-version of any trace of stability in either the beings or in us. In Myles Burnyeat's words, Socrates ultimately conjoins “Berkeley's dissolution of physical objects into a series of ideas perceived with Hume's dissolution of the self into a series of perceptions.” What results is an unqualified relativism in a world of universal flux. The thesis that Socrates develops ultimately denies the persistent identity of both humans and beings. Socrates achieves this outcome by linking Theaetetus' definition, Socratically interpreted, with Socratic versions of Protagoreanism and Heracleiteanism. In this mutated form, Theaetetus' newborn child must seem to him to have grown in some unforeseen ways.

Introduction

On the basis of his discovery of the distinctive power of the soul, Theaetetus produces a new definition: knowledge is true opinion. This definition seems crucial to the examination of knowledge as Socrates understands it. Throughout the Platonic corpus he approaches the meaning of knowledge by distinguishing it from opinion. The very need for Socrates' inquiries arises out of a sense of the inadequacy of opinion. Socrates does not discover the distinction between the Way of Truth and the Way of Seeming. He does, however, acquire an insight regarding the imperfect separateness of the two realms. It is this insight that mandates the examination of opinion characteristic of Socratic inquiry.

Socrates' philosophizing retains a significant tie to opinion because it culminates in knowledge that is explicitly partial. Animated as it is by the incompleteness of opinion, Socratic inquiry does not fly wholly free of its bonds. The Theaetetus is paradigmatic in this regard, most obviously because of its culmination in explicit aporia (210b8–9). However, the dialogue as a whole also illuminates the manner in which opinion exerts its influence on inquiry, shaping its concerns, and even informing what it is we take knowledge to be.

Socratic philosophy appreciates the significance of opinion because it considers most deeply the implication of the partiality of knowledge. As reflective of our self-experience, the problem of knowledge actually asks how we can know only partially.

Introduction

Socrates' continued assessment of Theaetetus' offspring subsequent to the Digression brings to bear the lessons learned in that crucial passage. As reflected in the order of topics and the treatment of each topic, Socrates begins his inquiry with facts about political life. He does deal once again with the three-legged thesis, generated with his guidance, but not in the order originally presented. Rather, he takes up once more the treatment of Protagoras that immediately preceded the Digression. Only subsequently does he turn to the Heracleiteans' notion of being and finally to Theaetetus' original definition.

In his continued treatment of Protagoras' thought Socrates connects an examination of political life, and especially the rule of law, to those limits of our knowing that follow from the elusiveness of the human good. The one who appreciates these limits, and their source, emerges as the true measure. Socrates, “the nonknower,” replaces the “wise” possessor of a techne with the seeker of phronesis, the one who acknowledges the need to seek the good.

Socrates' examination of law explicitly postpones the previously announced need to consider being. By this deed, he shows that political life provides a less distorting access to our nature and nature as a whole than the direct confrontation with being. That direct confrontation might well obscure what being must be insofar as law is possible and necessary. When Socrates does turn to being, he notes this danger by characterizing the proponents of competing views of being in frankly political terms.

Introduction

At the outset, I claimed that only through careful attention to the political content of the dialogue could we understand Plato's examination of the meaning of knowledge in the Theaetetus. Such attention enables us to see more clearly that, and why, knowledge is a problem. It allows us to appreciate as well the ongoing significance of that problem for the practice of philosophy. Because that significance persists, consideration of political life remains a requisite of philosophic inquiry.

The rationale for this requirement derives ultimately from the importance of the question of human good and the enduring perplexities surrounding its determination. We have access to the range of issues surrounding this question especially through the cognitive capacity called phronesis. The same considerations that make political inquiry central to philosophy designate wisdom, philosophy's object, as phronesis. In the Theaetetus, Socrates clothes phronesis in the garb of midwifery. He formulates this practice in recognition of the problems that attend philosophic inquiry and the existential significance of those problems. This being the case, Socrates' maieutics stands already as an achievement of phronesis. It is also the means to its further acquisition. Accordingly, in the concluding passages of this his valedictory, Socrates leaves for Theaetetus, and for any potential Socratic philosopher listening in, a picture of his strange, perplexity-inducing activity. In this final act of midwifery, he lets the wise midwife stand as the image of his life, available for any willing and able to emulate.

Aristotle opens Metaphysics A with a reflection that points to the emergence of ethics, as an explicit discursive articulation, after a long trajectory of human endeavors and inquiries – in fact, as the culmination of the unfolding of human seeking. In the order of knowing, the discourse of ethics will have come onto the scene after those other discussions, including the so-called metaphysical treatises: that which is closest to us, indeed most immediately crucial in and for us, reveals itself last, can be glimpsed at only toward the end of an exploration variously oriented outward, taking us far from ourselves, away from the beginning that we provide and are. The trajectory of such an exploration, thus, in the end leads one back to the previously unquestioned beginning, in order to unravel, to make explicit what was implicit, implied, and implicated in the beginning. In this trajectory the exploration ends up turning upon itself, catching a glimpse of its source and informing principles. It ends up somehow reflecting upon itself.

Thus, out of the “logical,” “physical,” and “metaphysical” texts would emerge the questions of cognition, of the manifold forms of life, of the relation between knowledge and comportment, eventually of the distinctively human. But of course, albeit in an implicit, unthematized fashion, the human would have been in play since the beginning of such investigations, as their very possibility – as the condition silently underlying their discourses.

The Aristotelian treatise transmitted under the title Ēthikōn Nikomakheiōn presents itself as a comprehensive reflection on the problem of human behavior. The word ēthos signifies precisely disposition, character in the sense of psychological configuration, and hence comportment, the way in which one bears oneself. However, the semantic range of the term exceeds this determination and signals that it must be situated in the broader context of custom, of shared usage, and even understood in the archaic but abiding sense of the accustomed place where the living (animals, plants, or otherwise) find their haunt or abode.

When describing Paris in shining armor rushing through the Trojan citadel in order to reach Hector, the poet of the Iliad resorts to the image of a well-fed horse breaking free from captivity, glorious in its splendor as it gallops “to the haunts and pastures of mares [μετά τ᾽ ἤθεα καὶ νομὸν ἵππων]” (VI.511). Ēthos is here the place in which a particular animal belongs, where others of the same kind gather and thrive. Belonging somewhere, then, means to find there the possibility of flourishing, of finding the most appropriate conditions to unfold and become whatever a being happens to be. The free horse at once moves in the direction of the haunts of horses, not unlike the way in which earth moves downward, in the direction of earth, and fire upward, in the direction of fire.