The Cave Story
Plato (c. 428-348 BCE) believed that only philosophers understand what the world is really like. Philosophers discover the nature of reality by thinking rather than relying on their senses. To make this point, Plato described a cave.
Inside an imaginary cave there are people chained, facing a wall. In front of them they can see flickering shadows made by objects held up in front of a fire that’s behind them. These people spend their entire lives thinking that the shadows projected on the wall are the real world.
Then, one of the people breaks free from his chains and turns toward the fire. His eyes are blurry at first, but then he starts to see where he is. He stumbles out of the cave and eventually is able to look at the sun. When he comes back to the cave, no one believes what he tells them about the world outside the cave.
The man who broke free is like a philosopher. He sees beyond appearances. Ordinary people, on the other hand, have little idea about reality because they are content with looking at what’s in front of them, rather than thinking about it deeply — but the appearances are deceptive since what are seen are shadows, not reality.
A Little History of Philosophy