Existentialism is less a single doctrine than a family resemblance among thinkers who put the same question first: what does it mean to exist as a human being, here and now, with a life to live and no guarantee about how it should go? Rather than starting from abstract systems, existentialists start from lived experience: choosing, worrying, loving, failing and dying.

Existence precedes essence

The slogan most associated with the movement comes from Jean-Paul Sartre in 1945: existence precedes essence. A manufactured object, such as a paper knife, has an essence before it exists: someone designs it for a purpose, then makes it. Sartre argued that humans are different. We exist first and only then define ourselves through what we do. There is no fixed human nature or blueprint, handed down by God or by biology, that settles in advance what a person must become. Not every existentialist accepted Sartre's atheist version of this claim, but nearly all agreed that a human life is something one has to make, not merely discover.

Four key themes

• Freedom. We are always choosing, even when we refuse to choose. Existentialists stress that this freedom carries responsibility for who we become: we cannot simply blame our circumstances, our upbringing or our society.
• Anxiety. Many existentialists distinguish anxiety (also translated as dread or anguish) from ordinary fear. Fear has a definite object, such as a snarling dog; anxiety is a diffuse unease before our own freedom and the openness of the future. Kierkegaard compared it to the dizziness of looking down into an abyss.
• Authenticity. To live authentically is to own one's choices and live by values one has made one's own, rather than drifting along with what everyone does or hiding behind roles and excuses. Its opposite is conformity and self-deception.
• Finitude and the absurd. We die, we cannot know everything, and the universe offers no obvious answer to why we are here. Some existentialists treat this as a call to faith; others as a call to courage.

Why it arose

Existentialism had two moments. The first came in the nineteenth century. Søren Kierkegaard reacted against the grand philosophical system of G.W.F. Hegel, which seemed to explain all of history while leaving no room for the single person facing a real decision. Friedrich Nietzsche responded to the fading of religious belief in modern Europe. Industrial cities, mass politics and the decline of traditional communities made many people feel like anonymous parts of a machine.

The second moment came in mid-twentieth-century France, after two world wars, the Nazi occupation and the Holocaust. Old assurances about progress and reason looked shattered, and questions of choice and responsibility were urgent: whether to collaborate or resist was a real decision people faced. The word existentialism itself only came into common use in the mid-1940s, when it was applied to Sartre and his circle. Sartre at first resisted it, then adopted it.

A loose family

The thinkers in this course disagreed sharply. Kierkegaard was a passionate Christian; Nietzsche announced the death of God; Heidegger and Camus both rejected the existentialist label. What unites them is a style of questioning: starting from the concrete situation of the individual rather than from detached theory, and treating the meaning of life as a problem each person must face personally. Literature mattered as much as treatises. Several of these writers made their case through novels, plays and parables, because they thought lived situations reveal what abstract argument misses.

Worked example: choosing a career

Maya is twenty-two. Her parents are both lawyers and have always assumed she will be one too. She has been accepted to law school, but she also has an offer to work for a small theater company. Let us look at her situation through this level's themes.

Freedom. Maya might say, “I don't really have a choice; my parents expect it.” An existentialist would point out that letting her parents decide is itself a choice, one she is responsible for. She cannot avoid choosing; she can only choose how.

Anxiety. Maya feels a strange dizziness when she thinks about the decision. Nothing is threatening her, so this is not fear of a definite object. It is anxiety before her own freedom: either path is genuinely open, and nothing outside her will settle it.

Existence precedes essence. Maya keeps asking which career is her “true calling,” as if her nature were already written somewhere and she only had to read it. Sartre would say there is no such hidden blueprint. She will become a lawyer or a theater worker by doing it.

Authenticity. Notice that authenticity does not require rebellion. If Maya chooses law because she has thought it through and wants that life, the choice is authentic. If she chooses theater only to defy her parents, she is still letting them define her. What matters is whether the choice is owned.

Finally, notice the historical point: Maya's dilemma is ordinary and private, but for existentialists such ordinary moments are where philosophy really begins.