Where other philosophers searched for the stable element that underlay the universe, Heraclitus saw ceaseless flux and transformation. He is also quoted by Plato as saying: ‘Everything flows. Nothing stands still.’ Nothing exists separately and permanently in itself, but everything is part of the interconnected flow of nature. The universe is a dance of opposites, each thing turning into something else: ‘Cold things become hot; hot things, cold. Wet things dry, dry things wet.’
