Class 6 - Socrates Responds to Theaetetus's Second Definition

2025-02-20
4 min read

Welcome back!

To get started, I want to explore your responses to the reading (this is section 187b–201c of the text). In breakout groups, discuss the following questions.

We’ll feed back to the main group at the end.

  1. What most interested you about the reading? Choose one sentence that particularly struck you.
  2. What did you find difficult or challenging about the reading?
  3. What are the major questions that Socrates and Theaetetus are exploring?
  4. What proposal does Theaetetus make about the nature of knowledge?
  5. How does Socrates respond to this proposal?

Knowledge is True Belief?

The main proposal that Theaetetus makes in this section is that knowledge is true belief (or true judgment).

Let’s look in more detail at Theatetus’s proposal, and at Socrates’s objections to this proposal.

What is a false belief?

The question in the text is how we can establish that knowledge is true belief. Socrates goes about exploring this by asking what it means to have a false belief.

This is much more complicated than you would think! Theaetetus gives five accounts of false belief. We’ll explore three accounts today, and two in the next session.

Writing Exercise: False Beliefs!

Let’s try an exercise! Write for 8 minutes about things you once believed that you now know are not true.

Now, in groups, talk about the following questions:

  1. What were the consequences of holding these false beliefs?
  2. How did you come to realise these beliefs were false?

The Big Question

This leads us to this following big question that we’ll be talking about today — one we’ve already raised: What is false belief?

Let’s look at the first three accounts of false belief that Theaetetus and Socrates explore, as they attempt to answer this question.

Account 1: False belief is misidentification

False belief is believing something is something else. It is misidentifying X as Y.

There are two possibilities here.

  1. We genuinely know both X and Y, but somehow misidentify them.
  2. We don’t know either X or Y.

Problems with Possibility 1:

If possibility 1 is true (we know both X and Y) we can’t misidentify them. Why? Because, as Sophie-Grace Chappell writes:

I cannot mistake X for Y unless I am able to formulate thoughts about X and Y. But I will not be able to formulate thoughts about X and Y unless I am acquainted with X and Y. Being acquainted with X and Y means knowing X and Y; and anyone who knows X and Y will not mistake them for each other.

Problems with Possibility 2:

If possibility 2 is true, we can’t form beliefs about X and Y in the first place, so we can’t misidentify them.

So let’s move on to another account.

Account 2: False belief is believing what is not the case

Problems with Account 2:

Can you believe what is not the case? If you believe something about X, but X is nonexistent, in what sense is this even a belief?

Sophie-Grace Chappell writes:

Socrates observes that if “what is not” is understood as it often was by Greek thinkers, as meaning “nothing,” then this proposal leads us straight into the sophistical absurdity that false beliefs are the same thing as beliefs about nothing (i.e., contentless beliefs). But there can be no beliefs about nothing; and there are false beliefs; so false belief isn’t the same thing as believing what is not.

Account 3: False belief is crossed wires between two true beliefs.

Crossed wires?

We believe something true about X and something true about Y. But we get our wires crossed and assign our beliefs about X to Y, or vice versa.

In the text, this is where Socrates talks about this:

We claim belief is false as a sort of ‘other-believing’, namely when someone claims that one of the things that are is another of the things that are because he’s swapped them over in his mind. This way what his belief is about is still something that is, only one such thing in place of another, and because he fails to hit on what he was aiming at he’ll justly be said to be believing what is false. (189b10 - c4)

Problems with account 3

But this runs up against the same problem as before: that truly knowing something rules out the possibility of being mistaken about it.

So what does it mean to be truly know something? We’ve still, apparently, made no progress on this question.

Discussion

  1. Which of these three accounts of false belief seems most convincing?
  2. Which of these three accounts of false belief seems least convincing?
  3. How convincing are the counter-arguments here?

Next time…

Next time, we’ll look at two more puzzles when it comes to false belief. These may be a little easier to grasp.

Homework

For your homework, I want you to read the entirety of Reading 03. Come prepared to discuss this next time. I’ll open up a new discussion thread on the discussion board.

Next Class 5 - Socrates Responds to Theaetetus's First Definition