Knowledge and Virtue in Plato's Theaetetus: Part One

by Gordon L. Ziniewicz

1. When reading the Theaetetus, one should keep in mind the fact of Socrates' trial and death and the fact of Socrates' activity as midwife and physician of the soul. Plato intends that the arguments of the Theaetetus be understood in the context of Socrates' mission to educate his fellow Athenians even to the last days of his life. The Socrates of the Theaetetus is, in many important ways, still the Socrates of the Apology -- a therapist of souls and a purger of false opinions, who knows that he does not know and learns by helping other people to see for themselves. From an epistemological point of view, the Theaetetus seems inconclusive; the dialogue is aporetic and the character Socrates is engaging in negative dialectic. But more is at stake in the Theaetetus than epistemology; there is an undeniable ethical drama taking place. Socrates is faced with death, and his companions are faced with confusion about priorities.

2. Early in the dialogue, an important Platonic theme is revisited: the difference between the expert (who knows what is meant by genuine measure and proportion) and the pseudo-expert (who thinks himself a measure). Talking about experts makes sense in a discussion with Pythagoreans who could be expected to agree that there are experts in the mathematical disciplines of arithmetic, geometry, astronomy, and music (harmony). Socrates vouches for Theodorus' expertise as "an astronomer and calculator and musician, and in general an educated man."(145a) Of course, one might ask whether Theodorus' sense of proportion or grasp of mathematical symmetry qualifies him to judge proportion or lack of proportion (and harmony) in the human soul. Theodorus knows mathematical forms, but does he know the form of justice and whether it is reflected in the human soul? Is the mathematician qualified to measure souls? The question is one of expertise in "virtue or wisdom."(145b) How close is Pythagorean mathematics or even Theaetetus' mathematics (which apparently advanced beyond Pythagorean formulations to an investigation of the universal foundations of mathematics) to philosophical wisdom (that grounds both mathematics and just action in the human city)?

3. The young Theaetetus will have to undergo questioning by Socrates in order to see the noetic implications of his own mathematical discoveries, which advance beyond Pythagorean learning. Conversation with Theaetetus and Theodorus may very well show that the mathematician is more capable than the pragmatic politician in judging human souls. After all, Theodorus (despite certain Protagorean prejudices) is more right than wrong about both Theaetetus and Socrates, whereas the Athenian "judges" who misjudged Socrates were more wrong than right. Socrates himself, though not claiming to be an expert or "measure" in view of his own wise ignorance, nevertheless does claim to be skillful (sophos) in determining worthwhile from worthless thoughts. Socrates, the barren midwife of other people's insights, knows the difference between insight and mere opinion. He is expert at judging ideas which he can not himself produce.

4. Overall, the dialogue aims at a number of transformations: the transformation of Pythagorean into Theaetetan mathematics; the relocation of a theory of sensation within its proper bounds, over against an implied but not yet developed deepened theory of forms; and, most important, the conversion through negative dialectic of the souls of Theodorus and Theaetetus, so that they may no longer merely seem, but be, harmonious and in agreement with themselves. According to Plato (See Gorgias 507 - 508), one must be on friendly terms with oneself in order to be on friendly terms with another or with wisdom.

5. We hear high praise of Theaetetus, who is to distinguish himself not only in mathematics, but also in war and in conversation with Socrates (which is often similar to war). Theaetetus is lauded as the ideal philosophical candidate, with the "right stuff" indicated by Socrates in the Republic. Theodorus introduces Theaetetus to Socrates, as geometry (in the Platonic sense) introduces the soul to dialectic. But the geometry of Theaetetus is not yet ready for Platonic dialectic. Pythagorean mathematics is still too tied to sense-perception. Mathematics itself must cross the divided line between opinion and knowledge before it can lead the way to dialectic. Mathematics must understand itself as knowledge of forms and not merely as construction of images.

6. But there is a further difficulty. Socrates claims that a midwife, who can tell a good result from a bad one, is also a competent matchmaker. Socrates knows what "marriages" of men and ideas are most likely to lead to insights. Socrates knows how to match up teachers and learners. The irony is that Theodorus has matched up Theaetetus with Socrates, not because he is an expert at such matches, but because, on this occasion at least, he happens to be right (right opinion). Theodorus does not judge either Socrates or Theaetetus perfectly (that would require a vision of the good), but his opinion is right. Yet Theodorus has in the past mis-matched Theaetetus with Protagoras. Geometry and Protagoras are not harmonious in Theaetetus' soul. Theodorus himself, who claims to be too old for dialectical reform and does not grasp the noetic foundations of geometry, does not see the contradiction between Protagorean relativism and Pythagorean mathematics. But Theaetetus feels and is bothered by this contradiction. That is the point of Theaetetus' unease and perplexity; he is uneasy about the relation between form and flux in his own soul.

7. Theodorus sees what Theaetetus and Socrates have in common (their snub-nosed appearance and predisposition to inquire), but he does not see how they differ, a critical mistake if knowledge means grasp of difference as well as identity (the common). The difference - the chief difference at any rate - between Theaetetus and Socrates is the hold that Protagorean and Cratylan relativism have on Theaetetus. Theodorus, a good friend of Protagoras, fails to see that the Theodorus and the Protagoras in Theaetetus cannot be good friends. Protagorean relativism is subversive not only of moral and political life, but also of geometry and other mathema. Theodorus, a geometer, is a friend of Protagoras, who himself is no friend of geometry, as evidenced in Protagoras' ironic and laconic writing on "Truth" (which lacks seriousness). Socrates knows that geometry has more in common with philosophical truth than Protagorean "Truth." He knows that mathematical insights have something in common with, though they differ from, philosophical insights. Socrates, both educator and moral therapist, sees that both Theodorus and Theaetetus must be cured of Protagoras before they are ready for philosophy, that is if they are to make the ascent from mathematical understanding to philosophical wisdom.

8. There is irony when Socrates asks whether "wisdom and knowledge are the same."(145e) For knowledge and wisdom are not the same thing. The Greek word sophos can mean skillful in any activity or techne (know-how). It can even mean knowledge or expertise; and that seems to be where Socrates is taking Theaetetus in the argument. But wisdom can also mean human (as opposed to divine) wisdom, the humility of "knowing that one does not know" that makes a person ready to learn and that promotes the very process of learning, as Socrates testifies in the Apology. This "human" wisdom is the child of poverty and plenty (see the Symposium). It means being on the right track (a quality of disposition or attitude) without having arrived. As a kind of moral transformation of one's attitude, it is different from competence (even expertise) in a particular subject matter (such as geometry). This sort of competence in a field seems to be Theodorus' sole understanding of wisdom, and Theodorus will need to be refuted in order to see that more is involved. Because of his perplexity, Theaetetus seems more predisposed to such "treatment" than Theodorus.

9. Theaetetus is like and unlike Socrates, but he is more like Socrates than he is like Theodorus. His therapy (the positive moral outcome of Socrates' negative dialectic) wii result in his "becoming" even more like Socrates. The dialogue examines motion and change in the context of living (and learning) souls that are moving and changing. Theaetetus and Theodorus really learn and really "become" better in relation to a Socrates who is comparatively steady (like a navigator who steers a steady course by relying upon the stable proportions of the heavens). Theaetetus will progress to the point of sharing Socrates' wisdom, his wise ignorance. In this sense, the Theaetetus dialogue, which fails to define knowledge, succeeds in making Theaetetus wiser. In the end, Theaetetus does not "know" more, but he knows better.

10. But the dialogue is to be a success in other ways as well. Not only will Theaetetus' soul be harmonized and predisposed to learning, but also certain Protagorean and Protagorean-like (in other words, Platonic) views of perception will be put in their proper place. A rather innovative view of sense-perception will be saved by putting it in perspective, by limiting its scope. Thus, we see in this dialogue both the measuring or staking out of the proper domains of sensation and thought and the moral straightening of the souls of Theaetetus and Theodorus.

11. In the Theaetetus, we see in concrete form the methexis of particulars and universals. Knowledge and virtue are not transcendent and apart from human affairs; they take place in people, who steer (phronesis) by means of transcendent standards of the true and the good. Socrates, unlike the pure spectator of the digression (later in the dialogue) and unlike the pragmatic "physician" of appearances - who makes those who feel bad feel good - genuinely purges the souls of his "patients" of the malady of bad ideas so that they will really, not apparently, get well. At the same time, he is a "physician" of arguments, purging them of words that do not belong and rearranging the words that do belong.

12. What is at stake in the Theaetetus goes beyond the abstract "staking out" of knowledge. There is an attempt to clear up the sophistic haze - the smoke and the mirrors - that obscures the ethics and politics of Athenian "legal eagles" who are unable to rise above the swirl of subjective (private) and immediate perception of expedient particulars (in which they have a vested interest) to the higher atmosphere of insight into universal and unchanging structures (such as justice). What is needed is an ascent from the cave of picture-thinking and opinion-marketing. The sophists and politicians are masters at manipulating images below ground; but they know nothing of the intelligible world above ground. Theodorus and Theaetetus need to do better; the well-being of their souls depends upon the realization that morality can be as stable as mathematics.

13. Though the discussion of doxa in the Theaetetus "seems" to elevate opinion (judgment) above the "divided line" drawn in the Republic, let us take the original divided line as a measuring stick, nonetheless. We see, somewhat to our disappointment, that the bulk of the argument takes place below the line dividing opinion from knowledge. Theodorus and Theaetetus must be coaxed to see above this line. They must be made to see that sensation is sensation and that opinion is opinion. Neither of these is knowledge. In order to reach this insight, they must be able to see the implications of their own mathematical discoveries - that geometric truths are not private understandings subject to public debate, but universal conceptions valid for all. Theaetetus, who suspects that not every man is an expert in geometry, must be made to see that the science of politics (which looks to absolute justice) is higher, not lower, than geometry and that the expert in justice is not every man (who very well may be an "expert" with regard to his feeling hot or cold). Justice is not a matter of taste. The sight of concrete particulars is different in kind from insight into eidetic universals. Geometry is the bridge between these two levels. The right ordering (harmonizing) of Theaetetus' soul (and the soul of the reader) depends upon his getting these matters straight and learning to turn his gaze above, not below geometry to find the form of justice. Thus the "delivery" and refutation of Theaetetus' misconceptions amounts to a reorientation and readjustment of Theaetetus' moral and epistemological priorities.

14. The argument as a whole must be viewed in the same way. One must be very careful how one takes Plato's presentation of antagonistic views. The theory of perception is a case in point. Very often, what is incorrect or out of place in one wave of conversation, can be redeemed if seen in a different context or under a different light. As we see later, in the refutation of the third definition of knowledge, a true account is not simply a collection of letters or syllables. It is how they are put together, how they are arranged that matters. Thus, Platonic arguments are constantly being rearranged, often using the same parts or elements. In the Theaetetus, many of the discarded building blocks are reusable, if one sees them differently, as foundation stones. For Plato, knowledge is never merely a matter of having forms (as birds in the aviary), but of arranging them properly (weaving them correctly, as the cosmos is well-woven). In the Theaetetus, some of the right words are there, but they await better arrangement, as Theaetetus' soul has many of the right ideas, but not in their proper places. The pursuit of knowledge requires at the same time the attunement (harmonizing) of the pursuing soul and the rearrangement of the elements of discourse. Both "corrections" require the very knowledge (of right order or arrangement) that they are pursuing. The standard for rearranging souls and speeches is both within and beyond souls and speeches.

15. In this light, a Protagorean-like formulation can be saved. For example, there is a truth implied in the Protagorean image of the sick man and the bitter taste. Seen as a metaphor, this image teaches us that only the healthy (just) soul "perceives" justice rightly. Just as there is an interdependence between perceiver and percipient in perception, so there is a kind of higher correspondence between the knower (as expert) and the known. The unhealthy (unjust) soul does not see clearly. As Socrates makes clear in the Republic, seeing higher forms requires turning one's whole soul toward the good; in a sense, only the good can see the good. Thus, learning is a process (motion) that works itself out as an adjustment between soul and form. Knowledge arises in this "interaction." One could even say that the meaning of a Platonic dialogue arises and changes in accordance with the soul of the reader. Learning itself is motion, flow, or flux. Theodorus says of Theaetetus, "he moves surely and smoothly and successfully in the path of knowledge and inquiry; and he is full of gentleness, flowing on silently like a river of oil...." (144b) The result of the motion of learning is the stasis of knowing.

16. By actively arranging and rearranging words and speeches, one gradually perceives more clearly the principles of right arrangement. It is never enough to merely "see" a form (in isolation). Insight requires grasp of order and arrangement, or seeing forms in their proper relation to one another. Complete wisdom (which Socrates attributes to the god), would be nothing less than a vision of all forms in their proper places, woven together (kosmos) and oriented to the good. Human speeches and lives participate in and approximate this arrangement.

17. The first part of the dialogue wrestles to overcome "knowledge is sense-perception" and stays well below the line dividing opinion and knowledge. The famous later "digression" interrupts the chain of argument and seems to float in an almost Parmenidean ideality far above the line dividing knowledge (of forms) and perception (of particular things). Thus, the argument becomes caught between Parmenideans and Heracliteans. The extreme opposition between the "way of truth" and the "way of opinion" in the digression might cure the malady of "knowledge is perception," but this treatment has potential side-effects. One might mistakenly leap from the frying pan of earth-bound pragmatic sensualism to the fire of impractical bodiless intellectualism, a danger pointed out by John Burnet in his Greek Philosophy (London: Macmillan and Co., 1928, p. 235). Wisdom is neither sensation of particulars nor mere thought of universals. The remainder of the dialogue is given over to refutation of "knowledge as true opinion" and "knowledge as true opinion with an account" (logos). One should keep in mind that even these discussions do not rise above the line between opinion and knowledge, although they are attempts to move in that direction. Doxa, with or without logos, is not dialectic.

Go to Part Two of this essay.


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Copyright © 1997 - 2013 Gordon L. Ziniewicz

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