Start with the trial dialogues
Euthyphro, Apology, Crito and Phaedo form a sequence around the trial and execution of Socrates in 399 BCE. Together they're about 150 pages and most editions print them in one volume, often titled The Last Days of Socrates.
They work as a first read because they're narrative. Something is happening, someone is going to die at the end of it, and the philosophy arrives inside a story rather than as a lecture. The Apology in particular is a courtroom speech, and it's magnificent.
| Dialogue | Reads as | Covers |
|---|---|---|
| Apology | Courtroom speech | Socrates' defence. The examined life. Start here. |
| Crito | Prison conversation | Whether to escape. Obligation to the law. |
| Phaedo | Deathbed scene | The soul, and his last hours. The ending is famous for a reason. |
| Symposium | Drunken dinner party | Love, by seven speakers. The most enjoyable dialogue. |
| Meno | Short argument | Can virtue be taught? Contains the slave-boy geometry lesson. |
| Republic | Long treatise | Justice, the ideal city, the cave, the forms. Book 1 and book 7 first if you're impatient. |
| Phaedrus | Walk by a river | Rhetoric, love, and a complaint about writing. |
The Republic problem
It's his masterwork, it contains the allegory of the cave, and it's a difficult first book. Ten books long, the political proposals are authoritarian enough to have made twentieth-century readers extremely uncomfortable, and the argument runs through analogies that take real patience.
If you're going straight there anyway, read book 1 for the argument with Thrasymachus, then book 7 for the cave, then decide whether to fill in the middle.
How much of it is Socrates
The Socratic problem, and it's unresolved. Socrates wrote nothing. Plato wrote him as a character across roughly 35 dialogues, and the views that character holds change substantially.
The rough scholarly consensus: the early dialogues are closer to the historical Socrates, mostly questioning and reaching no conclusion. The middle and late ones, including the Republic, use him as a mouthpiece for Plato's own positive doctrines, which the historical Socrates showed no sign of having.
Translations
The Hackett editions, many translated by G.M.A. Grube, are the standard for study and are cheap. Penguin Classics are fine and more readable in places. The Cooper-edited Complete Works is the one-volume everything, and it's a serious brick.
See also Aristotle, his student and opponent, and philosophy for beginners. 365 Days of Philosophy runs the whole tradition a page a day.
Common questions
Which Plato dialogue should I read first?
The Apology, usually read with Euthyphro, Crito and Phaedo as a sequence around Socrates' trial and death. They're narrative, they're about 150 pages together, and they're often sold in one volume.
Should I start with the Republic?
Most people shouldn't. It's ten books long and the argument demands patience. If you're going anyway, read book 1 and book 7 first.
How much of Plato's Socrates is the real Socrates?
Unresolved. The early dialogues are generally taken as closer to the historical figure, while the middle and late ones use him to voice Plato's own doctrines.
Which Plato translation is best?
Hackett editions, many by G.M.A. Grube, are the standard for study and inexpensive. Penguin Classics are more readable in places. Cooper's Complete Works collects everything in one volume.
What is the allegory of the cave?
From Republic book 7. Prisoners chained facing a wall take shadows for reality; one escapes, sees the world, and returns to disbelief. It's Plato's picture of education and of the theory of forms.