Alexander the Great

Plato, (born 428/427 bce, Athens, Greece—died 348/347, Athens), ancient Greek philosopher, student of Socrates (c. 470–399 bce), teacher of Aristotle (384–322 bce), and founder of the Academy, best known as the author of philosophical works of unparalleled influence.

1. Saint Thomas Aquinas (1225–1274)
2. Aristotle (384–322 BCE)
3. Confucius (551–479 BCE)
4. René Descartes (1596–1650)
5. Ralph Waldo Emerson (1803 82)
6. Michel Foucault (1926-1984)
7. David Hume (1711–77)
8. Immanuel Kant (1724–1804)

Much of Western philosophy finds its basis in the thoughts and teachings of Socrates, Plato, and Aristotle. You can’t begin a study of world philosophy without talking about these guys: the Big Three ancient Greek philosophers.

Platonic realism is the theory of reality developed by Plato, and explained in his theory of Forms. Platonic realism states that the visible world of particular things is a shifting exhibition, like shadows cast on a wall by the activities of their corresponding universal Ideas or Forms.

The main theme of Plato’s Allegory of the Cave in the Republic is that human perception cannot derive true knowledge, and instead, real knowledge can only come via philosophical reasoning. In Plato’s example, prisoners live their entire lives in a cave, only able to see shadows. To them, these shadows are reality.

Plato is an example of a rationalist. He says that sense experience fails to provide us with any guarantee that what we experience is, in fact, true. The information we get by relying on sense experience is constantly changing and often unreliable.