How does Jean-Paul Sartre’s existentialism connect freedom of choice with moral standards?

In the context of existentialism, Jean-Paul Sartre argued that because there is no God or predetermined human purpose, "existence precedes essence." Consequently, humans are not designed for any specific end and are radically free to determine their own values and way of life.1

Sartre viewed this freedom as an inescapable responsibility. To deny this freedom or claim one is compelled by circumstances to act in a certain way is to live in "bad faith". In his early philosophy, such as in Being and Nothingness, Sartre suggested that as long as an individual chooses "authentically," there are no objective moral standards by which their conduct can be criticized, a position that drew criticism for its radical subjectivism.213

However, in his later work, particularly the lecture Existentialism and Humanism, Sartre moved toward a more social perspective, suggesting that moral judgments should be applied universally. This shift reflected a growing concern for social responsibility and justice, eventually leading him to attempt to reconcile his philosophy of individual freedom with Marxism in his later writings.4135