Simone de Beauvoir on Doing What We Must
Regardless of the staggering dimensions of the world about us, the density of our ignorance, the risks of catastrophes to come, and our individual weakness within the immense collectivity, the fact remains that we are absolutely free today if we choose to will our existence in its finiteness, a finiteness which is open on the infinite. And in fact, any man who has known real loves, real revolts, real desires, and real will knows quite well that he has no need of any outside guarantee to be sure of his goals; their certitude comes from his own drive. There is a very old saying which goes: “Do what you must, come what may.” That amounts to saying in a different way that the result is not external to the good will which fulfills itself in aiming at it. If it came to be that each man did what he must, existence would be saved in each one without there being any need of dreaming of a paradise where all would be reconciled in death.
Simone de Beauvoir, from The Ethics of Ambiguity