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Who Was Plato?



Plato (428-348/347 B.C.E.)

Plato points to the heavens, his student Aristotle to the ground, in Raphael’s painting of the School of Athens (detail).

Plato's philosophy and its implications for Greek cosmology are understandable as a response to social and political troubles. Plato was of an age to enter public life when the Thirty Tyrants, including two of his relatives, ruled Athens. Their actions disgusted Plato. When their rule was overthrown, Plato again considered joining the government. But then the democracy persecuted his teacher and friend Socrates. Subsequent experiences, perhaps including an encounter with the dictator of Syracuse, confirmed Plato's dismay over the actions of rulers. He searched for unchanging standards to hold against the shifting judgments of men.

Copy of a Greek portrait bust with the nose reconstructed by guesswork.

In his famous allegory of the cave, Plato imagined men chained from childhood in a cave, so shackled that they must sit still, looking in only one direction. A fire behind them casts shadows of objects upon the cave wall in front of them. In the absence of any other experience, the prisoners accept the shadows as reality. Plato explained that the prison of the cave corresponds to the part of the world revealed by our bodily senses. Escape from the cave corresponds to the use of intelligence to reach the real world of knowledge.

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The Greek Worldview