“A society that does not recognize that each individual has values of his own which he is entitled to follow can have no respect for the dignity of the individual and cannot really know freedom.”

Source: Capitalism and Freedom (1962), Ch. 12 The Alleviation of Poverty

Une telle morale [la morale existentialiste] est-elle ou non un individualisme? Oui, si l’on entend par là qu’elle accorde à l’individu une valeur absolue et qu’elle reconnaît qu’a lui seul le pouvoir de fonder son existence. Elle est individualisme au sens où les sagesses antiques, la morale chrétienne du salut, l’idéal de la vertu kantienne méritent aussi ce nom ; elle s’oppose aux doctrines totalitaires qui dressent par-delà I’homme le mirage de l’Humanité. Mais elle n’est pas un solipsisme, puisque l’individu ne se définit que par sa relation au monde et aux autres individus, il n’existe qu’en se transcendant et sa liberté ne peut s’accomplir qu’à travers la liberté d’autrui. Il justifie son existence par un mouvement qui, comme elle, jaillit du coeur de lui-même, mais qui aboutit hors de lui.
Cet individualisme ne conduit pas à l’anarchie du bon plaisir. L’homme est libre ; mais il trouve sa loi dans sa liberté même. D’abord il doit assumer sa liberté et non la fuir; il l’assume par un mouvement constructif : on n’existe pas sans faire; et aussi par un mouvement négatif qui refuse l’oppression pour soi et pour autrui.
Conclusion http://www.marxists.org/reference/subject/ethics/de-beauvoir/ambiguity/ch04.htm
The Ethics of Ambiguity (1947)

Part I : Declaration, Ch. IV : Mr. Spencer's Confusion as to Rights
A Perplexed Philosopher (1892)
Context: Men must have rights before they can have equal rights. Each man has a right to use the world because he is here and wants to use the world. The equality of this right is merely a limitation arising from the presence of others with like rights. Society, in other words, does not grant, and cannot equitably withhold from any individual, the right to the use of land. That right exists before society and independently of society, belonging at birth to each individual, and ceasing only with his death. Society itself has no original right to the use of land. What right it has with regard to the use of land is simply that which is derived from and is necessary to the determination of the rights of the individuals who compose it. That is to say, the function of society with regard to the use of land only begins where individual rights clash, and is to secure equality between these clashing rights of individuals.

1920s, Authority and Religious Liberty (1924)

Conquest of Violence: The Gandhian Philosophy of Conflict by Joan V. Bondurant (1965) University of California Press, Berkeley: CA, p. 174. Harijan (1 February 1942) p. 27
1940s

As quoted in "Capitalism, Socialism, and Democracy: A Symposium" https://www.commentarymagazine.com/articles/capitalism-socialism-and-democracy/ (1 April 1978), edited by William Barrett, Commentary

The Irony of American History (1952)

The Art of Writing

Source: Modes and Morals (1920), Ch. 4