“A freedom which is interested only in denying freedom must be denied. And it is not true that the recognition of the freedom of others limits my own freedom: to be free is not to have the power to do anything you like; it is to be able to surpass the given toward an open future; the existence of others as a freedom defines my situation and is even the condition of my own freedom. I am oppressed if I am thrown into prison, but not if I am kept from throwing my neighbor into prison.”