To make the form, nature, content, future course, etc., of (something) different from what it is or from what it would be if left alone: to change one’s name; to change one’s opinion; to change the course of history.
– http://dictionary.reference.com/browse/change
“‘Everything flows,’ said Heraclitus. Everything is in constant flux and movement, nothing is abiding. Therefore we ‘cannot step twice into the same river.’ When I step into the river for the second time, neither I nor the river are the same.”
– Jostein Gaarder, in Sophie’s World: A Novel About the History of Philosophy