We will freedom for freedom’s sake through our individual circumstances. And in thus willing freedom, we discover that it depends entirely on the freedom of others, and that the freedom of others depends on our own. Of course, freedom as the definition of man does not depend on others, but as soon as there is commitment, I am obliged to will the freedom of others at the same time as I will my own. I cannot set my own freedom as a goal without also setting the freedom of others as a goal. Consequently, when, operating on the level of complete authenticity, I have acknowledged that existence precedes essence, and that man is a free being who, under any circumstances, can only ever will his freedom, I have at the same time acknowledged that I must will the freedom of others. Therefore, in the name of this will to freedom, implied by freedom itself, I can pass judgment on those who seek to conceal from themselves the complete arbitrariness of their existence, and their total freedom.
Those who conceal from themselves this total freedom, under the guise of solemnity, or by making determinist excuses, I will call cowards. Others, who try to prove their existence is necessary, when man’s appearance on earth is merely contingent, I will call bastards. But whether cowards or bastards, they can be judged only on the grounds of strict authenticity. Thus, although the content of morality may vary, a certain form of that morality is universal.
Jean-Paul Sartre 1946 Existentialism Is a Humanism