In particular those who are condemned to stagnation are often pronounced happy on the pretext that happiness consists in being at rest. This notion we reject, for our perspective is that of existentialist ethics. Every subject plays his part as such specifically through exploits or projects that serve as a mode of transcendence; he achieves liberty only through a continual reaching out towards other liberties. There is no justification for present existence other than its expansion into an indefinitely open future. Every time transcendence falls back into immanence, stagnation, there is a degradation of existence into the ‘en-sois’ – the brutish life of subjection to given conditions – and of liberty into constraint and contingence. This downfall represents a moral fault if the subject consents to it; if it is inflicted upon him, it spells frustration and oppression. In both cases it is an absolute evil. Every individual concerned to justify his existence feels that his existence involves an undefined need to transcend himself, to engage in freely chosen projects.
Simone de Beauvoir, The Second Sex