A conquest of this kind is never finished; the contingency remains, and, so that he may assert his will, man is even obliged to stir up in the world the outrage he does not want. But this element of failure is a very condition of his life; one can never dream of eliminating it without immediately dreaming of death. This does not mean that one should consent to failure, but rather one must consent to struggle against it without respite.
Conclusion - The Ethics of Ambiguity (1947)