Theaetetus

Returning to the question of knowledge, Socrates says that we perceive through the various sense organs. Everything gained though these senses converges on, and is united in, the “mind” (69). The mind then organizes and gives meaning to various sensory stimuli to form a coherent perception. In this way, the mind can consider things given to it by the body—yet it can also consider things by itself. It can form judgments about the “being” of something. This means it can use contrast and calculation to establish the nature of an object in terms of its likeness and difference to other objects, as well as its usefulness and aesthetic qualities. Further, it is the understanding of an object’s “being,” or nature, that constitutes knowledge.

Socrates draws his final conclusion about Protagoras’s theory. Since understanding the being of a phenomenon constitutes knowledge, knowledge cannot consist in perception. This is because perception does not give access to such being. Instead, any investigation into the meaning of knowledge must proceed by looking at “what the mind is doing when it’s busying itself, by itself, about the things which are” (71). In short, the enquiry into knowledge must look at the mind and reason if it wishes to find the truth. Theaetetus offers a preliminary point of orientation for such an enquiry by suggesting that “true judgment is knowledge” (72).

Examining Theaetetus’s suggestion that knowledge is true judgment, Socrates focuses on the distinction between true and false judgment, upon which this idea relies. He argues that false judgment cannot mean having a judgment about things that do not exist. This is because any sort of judgment must involve the invocation of a phenomenon that at the very least exists in the mind. For example, the idea of a cyclops exists as an idea in the mind of one who thinks about it. Thus, Socrates concludes, false judgment must mean something other than imagining things that do not exist.

Socrates attempts to find a solution to the problem of false judgments raised in Chapter 24. He puts forth the idea that false judgment might reside not in imagining something but in thinking something to be other than it is. Thinking is here understood as the mind’s internal dialogue with itself. For example, we might think to ourselves “X is beautiful” when it is in fact ugly. However, Socrates finds that this idea still falls prey to the same problems that face identifying false judgment with imagining something.

We might understand false judgment on the basis of accurate and inaccurate memory. Socrates uses the metaphor of a wax tablet to demonstrate this. When we perceive something, an impression of that thing is imprinted on our mind and memory, as an object leaves an impression on wax. However, false judgment occurs when this imprint from an initial perception is imperfect. It may then happen that this initial imprint does not correspond to a subsequent perception of the same thing. Consider, for example, the case of a person we know but have not seen in years. As our memory of them is imperfect, we may incorrectly judge a different but similar person to be them, or we may fail to recognize them when they are there. This is how false judgment occurs.

Moreover, Socrates argues that this is possible because different people have varying qualities of “wax” for their minds. Some have thick, consistent, and pure wax, and therefore can learn and remember accurately. Others have wax that is impure or excessively fluid or hard, and are thus more prone to poor memory and false judgment.

Socrates identifies a problem with the wax tablet analogy as a means of resolving the problem of false judgments. Namely, it only applies to the relationship between perception and thought, and not the operations of thought itself. For instance, false judgment still presents a problem in the case of reflection on numbers. It seems impossible to judge four to be five, even at some future point, once we know what these numbers mean. As such, Socrates tries a different tack. He hopes to make progress by “being prepared to say what knowledge is like” (87). In other words, he hopes to discover a more productive route in his quest for a definition of knowledge by looking at the way we know something.

To examine the way we know things, Socrates uses the metaphor of the mind as an aviary and draws a distinction between “having” and “possessing” (88). As he argues, we can possess something without having it at any given moment. For example, you may own a coat but not have it in your possession right now. Imagining pieces of knowledge in the mind to be like birds in aviary, we may have caught a bird, or learned a piece of knowledge, but we do not have it in our hand, or at the forefront of our mind. To “have” the piece of knowledge we must therefore try and catch, or recollect, it from among other pieces of knowledge. With this idea, Socrates believes he has resolved the problem of false judgment. This is because it can still be said that it is impossible to not possess what one possesses, or to not know what one knows. However, when one tries to grasp a piece of knowledge one possesses, one may fail to do so at a given moment, or may misidentify something we have taken hold off. For example, you may wrongly attribute a certain quote to Heraclitus that was in fact said by Parmenides. Therein lies false judgment.