Plato was a Greek philosopher who lived between 427 and 347 BC. Plato argues that wisdom based on truth and reason is at the heart of the just person and the just society.
This extract describes prisoners trapped in a cave, watching shadows of life outside cast on the wall by the light of a fire. After a while they will think of the shadows as reality. But in truth reality is different and can only be known by those outside the cave who live in the light of the sun. Plato describes his statesmen (guardians) as people who have struggled to the sunlight of reason and learnt the truth about the material world (physics) and the moral and spiritual world (metaphysics.) Only such philosophers can be trusted to rule the state.