The most optimistic ethics have all begun by emphasizing the element of failure involved in the condition of man; without failure, no ethics; for a being who, from the very start, would be an exact co-incidence with himself, in a perfect plenitude, the notion of having-to-be would have no meaning. One does not offer an ethics to a God. It is impossible to propose any to man if one defines him as nature, as something given. The so-called psychological or empirical ethics manage to establish themselves only by introducing surreptitiously some flaw within the manthing which they have first defined.
Simone de Beauvoir, in The Ethics of Ambiguity (1947)