Existentialism Is a Humanism
Jean-Paul Sartre · 1946 · 10 ideas · 10 min
Sartre argues that because there is no God or fixed human nature to define us in advance, each person must create their own meaning through free choice, and in doing so bears full responsibility for humanity itself.
Why this book
Delivered originally as a lecture defending existentialism against critics who called it nihilistic, despairing, or immoral, Sartre's central argument is that human beings have no essence handed to them by God, nature, or biology; instead, "existence precedes essence," meaning we first exist and only afterward, through our choices and actions, define who we are. Because there is no predetermined human nature to fall back on, every person is radically free and radically responsible for shaping themselves, and by extension, for shaping an image of what humanity itself can be.
The book matters because it directly confronts the fear that a godless universe leads to moral chaos, arguing instead that authentic freedom demands more responsibility, not less, since choosing for oneself is simultaneously choosing on behalf of all humanity. Sartre frames this not as a bleak burden but as the foundation of a genuinely engaged, humanist ethics grounded in action rather than inherited rules.
Who should read it
Anyone questioning where meaning and morality come from without religious or predetermined answers, or readers encountering existentialism for the first time and wanting a compact, direct statement of its core claims, will find this valuable.
About the author
Jean-Paul Sartre was a French philosopher, playwright, and novelist, and a central figure of 20th-century existentialism; he was awarded the 1964 Nobel Prize in Literature, which he declined.