Our ancient ancestors did not much concern themselves with questions of from what the world was made, preferring to spend their days to exploring the possibilities of banging rocks together, sharpening them and using these to discover what animals are made from. However, a remarkable flowering of Philosophy in classical Greece changed all that. Suddenly learned men were prepared to spend time considering the very structure of the universe, possibly because ancient Hellenic culture offered few alternatives to un-athletic men without an unhealthy interest in goats.