ancient Greek philosopher (428/423 – 348/347 BC)

Plato (c. 427 – 347 BC) was one of the most important philosophers of all time.[1][2][3] Born to wealthy parents in Athens, Greece,[3] Plato was a student of Socrates[1][3] (who did not write) and, later, became the teacher of Aristotle.[1] Plato started a university in Athens called the Academy where he taught.[3] Plato wrote about many ideas in philosophy that are still talked about today, including political philosophy and the philosophy of language.[1] One modern scholar, Alfred North Whitehead, said that all European philosophy since Plato is a series of footnotes to his works.[4]

Roman copy of a portrait bust c. 370 BC
Born428/427 or 424/423 BC
Died348 BC (aged c. 75-76 or 79-80)
Athens, Greece
Notable work
EraAncient Greek philosophy
SchoolPlatonic Academy
Notable studentsAristotle
Main interests
Epistemology, Metaphysics
Political philosophy
Notable ideas
Allegory of the cave

Cardinal virtues
Form of the Good
Theory of forms
Divisions of the soul
Platonic love

Platonic solids



Plato wrote his books in the form of conversations called dialogues. In a dialogue, two or more people talk about ideas and sometimes disagree over them. The Laws is Plato's longest dialogue and probably his last.[5]

Plato pointing upwards in Raphael's painting The School of Athens in the Vatican. Plato's pointing is sometimes thought to symbolize Plato's theory of forms, which exist in another realm.

Socrates is usually the main person in Plato's dialogues. Often, Socrates talks with people and tries to see if they believe anything that is illogical.[6] Because of this, some people become angry with Socrates and try to kill him. In Plato's Apology, Socrates is put on trial by these people and is eventually sentenced to death by drinking poison.[7]

Theory of Forms


Plato is famous for developing the theory of forms. This theory says that everything in our world is imperfect but corresponds to a perfect version of itself that exists in another realm.[2]

For example, there are wooden chairs, metal chairs, square chairs, big chairs, small chairs, etc. All the chairs we can ever sit in, according to Plato, are imperfect versions of the perfect form of “chairness,” the ideal chair. The same is true of every other object our senses can perceive: it is imperfect but corresponds to a perfect version of itself.

One simple way to think about Plato's theory is with numbers. The difference between "chairness" and a regular chair is similar to the difference between the number five and having five apples, oranges, pears, etc.[8]

In other words, Plato thought that the world we live in is just a shadow of the real, "intelligible realm," which only a few people will ever understand. He thought that all perfect forms come from perfection itself, which he called "the good.”[9]

Plato vs. Socrates


People who study Plato argue about whether Socrates really said the same things that Plato makes him say, or whether Plato just used Socrates as a character to make the ideas he was talking about seem more important.[6]

Works by Plato


There are many dialogues that were written by Plato. This list includes those he probably did write:



  1. 1.0 1.1 1.2 1.3 "Plato | Life, Philosophy, & Works | Britannica". 11 February 2024. Retrieved 17 March 2024.
  2. 2.0 2.1 Kraut, Richard (2022), Zalta, Edward N. (ed.), "Plato", The Stanford Encyclopedia of Philosophy (Spring 2022 ed.), Metaphysics Research Lab, Stanford University, retrieved 17 March 2024
  3. 3.0 3.1 3.2 3.3 Willers, Michael (2021). Mathematics: From Algebra to Algorithms, Adventures in Numbers. London, UK: New Burlington Books. pp. 50–51. ISBN 978-1-80242-020-3.
  4. "Alfred North Whitehead - Wikiquote". Retrieved 17 March 2024.
  5. Bobonich, Christopher (2010). Plato's Laws: A Critical Guide. Cambridge University Press. p. 1. ISBN 978-0-521-88463-1.
  6. 6.0 6.1 Plato (2005). Early Socratic Dialogues. Great Britain: Penguin Group. pp. 13-36. ISBN 978-0-140-45503-8.
  7. "The Project Gutenberg eBook of Apology, by Plato". Retrieved 18 March 2024.
  8. Willers, Michael (2021). Mathematics: From Algebra to Algorithms, Adventures in Numbers. London, UK: New Burlington Books. pp. 42–43, 50–51. ISBN 978-1-80242-020-3.
  9. Plato (2004). The Republic. United States of America: Hackett Publishing Company, Inc. pp. 204–205. ISBN 978-0-87220-736-3.