Theaetetus
A young mathematician proposes that knowledge is perception, then true judgment, then true judgment with an account. Socrates tests each proposal through discussions of Protagoras, perceptual change, false belief and the puzzling requirements of explanation.
Understanding the text
The dialogue’s frame remembers Theaetetus after a battle; the conversation itself precedes Socrates’ trial. It offers no final definition of knowledge.
Key points
- 01
Perception and relativism
The claim that appearances are true for each perceiver must explain disagreement, expertise and judgments about future outcomes.
- 02
False judgment
Images of a wax tablet and an aviary explore how someone can possess information yet misidentify or misuse it.
- 03
An account
Adding elements, enumeration or a distinguishing mark to true belief does not automatically yield the understanding that knowledge requires.
Explore the ideas in depth
What is knowledge?
Socrates and the young Theaetetus examine in turn the proposals that knowing is perceiving, having a true judgment, and adding an account to true judgment. Each initially seems promising, but discussion exposes further difficulties. The dialogue ends without an accepted definition.
Perception and examination
The first proposal leads to discussion of the relativity associated with Protagoras and theories of change. Socrates’ image of midwifery describes questioning as helping others test their thoughts. The absence of a final answer does not prove every opinion equally sound; it shows the work that remains.
How to read it
Make a chart of definitions and objections, separating Socrates’ temporary defence of a position from his eventual criticism. The failure of an answer is a result worth understanding.
Editions & sources
Summaries and key points are original editorial interpretations. They accompany reading the work and do not replace an edition of the text. Editorial method ↗