Summary of Theaetetus

Key point 1 of 6

Socrates the midwife asks what knowledge is

The dialogue opens with a frame. Two men, Euclides and Terpsion, meet in Megara and speak of Theaetetus, who has been carried home from an army camp near Corinth, wounded and ill. Euclides says he once wrote down a conversation that Socrates had with the boy long ago, and a slave now reads it aloud. That written conversation is the rest of the book.

In it, Theodorus praises Theaetetus as quick, gentle and brave in learning. Theaetetus has been working on mathematics, and he has helped show how to deal with square roots that cannot be written as simple ratios. Socrates asks him a question that sounds easy. What is knowledge? Theaetetus first lists things that can be known, such as geometry and the craft of the cobbler. Socrates points out that a list is not an answer. He asks for what all these things share.

Theaetetus feels the difficulty and says it makes his head spin. Socrates then explains his own craft. His mother was a midwife, and he does the same work for minds. He cannot give birth to ideas himself, but he can tell whether an idea from a young thinker is healthy or only a false pregnancy. Many ideas will be tested and some will be thrown out.

This opening sets the method for the whole book. The aim is not to hand over a definition but to bring one out and judge it fairly. It also gives the first lesson. A good question demands more than examples, and the discomfort of not knowing is where real thinking begins.

Socrates adds that wonder is where a philosopher starts. That is why he welcomes the boy's confusion instead of calming it.