What Is Existentialism? Sartre, Kierkegaard, Camus and Why Your Existential Crisis Is Normal

Last updated: November 2, 2026

Existentialism is the philosophy that starts from one awkward fact: you exist before you know what you are for. Nobody hands you a manual, and there is no factory setting called “your purpose”. So, existentialists say, you make yourself through the choices you make, and you cannot outsource the responsibility for them to God, your parents, your genes or your boss.

That is the whole idea in two sentences. The rest of this post is about why it caused a riot, why it feels so uncomfortable, and why it is oddly good news.

Did You Mean: Make Your Purpose?

The meme above is existentialism in one search bar. Someone types “how to find my purpose in life”, and the search engine politely corrects them: did you mean “how to make my purpose in life”? The joke is that the question assumes the purpose is out there somewhere, hidden like a lost key, and the existentialist answer is that there is nothing to find. There is only something to make.

Existentialism is a family of ideas rather than a club with a membership card, but almost everyone in the family agrees on three things. First, you come before your purpose. A hammer is made for hammering, while a human being is not made for anything in particular, at least not in a way you can look up. Second, that makes you free and responsible at the same time. If there is no script, there is nobody to blame for how you play the part, which is why existentialists are allergic to the sentence “I had no choice”. Third, freedom comes with a mood. Anxiety, dread, nausea and the sense that things are absurd are taken seriously as information about the human situation, not only as problems to medicate away.

What really sets existentialism apart is the angle. Most philosophy describes the world from above, as if you could float outside your own life and take notes. Existentialists insist on the view from inside: one particular person, in one body and one century, who has to decide what to do on Tuesday. Kierkegaard put it in a sentence that sums up the movement: life can only be understood backwards, but it must be lived forwards. You never get the full picture before you have to act.

Apricot Cocktails and Broken Chairs

The movement has an origin story with a drink in it. Around the turn of 1933 Jean-Paul Sartre, Simone de Beauvoir and their friend Raymond Aron were drinking apricot cocktails at the Bec-de-Gaz bar on the rue Montparnasse. Aron had just come back from Germany, where he had discovered phenomenology, a way of doing philosophy that describes experience exactly as it shows up instead of theorising about what lies behind it. He pointed at his glass and told Sartre that with this method you could make philosophy out of the cocktail. Sartre, according to Beauvoir, went pale with excitement. Philosophy about cafés, waiters and park benches was exactly what he wanted to write, and he went to Berlin for a year to study Edmund Husserl. The historian Sarah Bakewell later named her book about the movement after that drink: At the Existentialist Café: Freedom, Being, and Apricot Cocktails.

The word came later. The Catholic philosopher Gabriel Marcel introduced “existentialism” in 1943, Sartre at first waved it away, and by 1945 he had adopted it. After the war it spread to the young people in black polo necks in the cafés and jazz cellars of Saint Germain des Prés. Existentialism became a style before most people had read a page of it.

Then came the riot. On 29 October 1945 Sartre gave a public lecture in Paris called “Existentialism Is a Humanism”. The hall was overheated and overpacked, around thirty chairs were broken, the box office was wrecked and fifteen people reportedly fainted. One paper ran the headline “Too Many Attend Sartre Lecture. Heat, Fainting Spells, Police.” Why would a philosophy talk pull a crowd like a rock concert? France had just come out of the German occupation, where everyone had faced real choices about resistance, collaboration and looking away. A philosophy that said you are always responsible for what you choose landed in a country that knew exactly what that meant.

A Paper Knife and the Cards You Were Dealt

The movement’s slogan is “existence precedes essence”, and Sartre explained it in that lecture with a very unglamorous object: a paper knife. Before a paper knife exists, someone has already decided what it is for. The craftsman has the purpose and the production method in mind and then makes the thing, so for the knife essence comes before existence. People, Sartre says, are the reverse. If there is no designer who had you in mind, there is no blueprint you are supposed to match. You turn up first, and then you define yourself. In his words: “Man is nothing other than what he makes of himself.”

That is a bigger claim than it sounds. For two thousand years Western philosophy mostly assumed a human nature that tells you what a good life looks like. Sartre says that for an atheist there is none to fall back on. You still have a biology, but nothing in your biology tells you what to do with your life. That is why existentialists grow suspicious whenever someone says “that is just who I am”. Who you are is the running total of your choices, and the total can still change.

The obvious objection is that I did not choose where I was born, what body I have or how much money my parents had. Existentialists agree, and they call it facticity: everything about you that is simply given, from your date of birth to the century you live in. Martin Heidegger described it as being “thrown” into the world. You did not apply for this life, you landed in it, already in the middle of things. The other half is transcendence, your ability to interpret those facts and decide what to do with them. You cannot choose whether you have a stammer. You can choose whether it ends your interest in public speaking.

Sartre became more modest about freedom as he got older. In a 1969 interview he limited it to “the small movement which makes of a totally conditioned social being someone who does not render back completely what his conditioning has given him.” His friend Maurice Merleau-Ponty had a neater formula: we choose the world, and the world chooses us.

Condemned to Be Free, and Dizzy With It

If nobody wrote your manual, every choice is on you, which is why Sartre called us “condemned to be free”. Freedom here is not a holiday. It is a job you cannot quit, because even refusing to choose is a choice. He took his starting point from Dostoevsky, who has a character suggest that if God does not exist, everything is permitted. Without a divine rulebook there is no outside authority to settle what you should do. Whether morality really collapses without God is a separate fight, covered in our post on Dostoevsky and objective morality.

His favourite example came from occupied France. A student had to choose between joining the Free French forces in England, partly to avenge his brother, and staying home with his mother, who lived only for him. Christian ethics, Kantian ethics and gut feeling all pulled in both directions. Sartre’s answer sounds cold at first: “You are free, so choose; in other words, invent.” He called the resulting feelings anguish, abandonment and despair, and the upside of all three is that nobody else gets to write your story either. If you want the versions of freedom sorted, read our post on absolute freedom.

Søren Kierkegaard had described the feeling a century earlier. In The Concept of Anxiety (1844) he compares it to standing at the edge of a cliff. The drop scares you, but what really makes your head spin is that you could jump, and nothing stops you except you. His summary is one of the best lines in philosophy: “anxiety is the dizziness of freedom.” That is why existential dread rarely has a clear object. You are not afraid of a spider, you are uneasy about the size of your own options.

An existential crisis, in other words, is not a malfunction. It pulls you off autopilot, and for a moment you are not an employee or a customer but someone who has to decide what to do with a finite life. Heidegger built a philosophy around that finitude, which we unpack in Heidegger’s being-towards-death. Kierkegaard’s darker sequel is in Kierkegaard’s concept of despair, and his take on total boredom in Kierkegaard and ennui. If the feeling sticks around and gets heavy, talking to someone is a better next step than reading more Kierkegaard, and our post on philosophy in psychotherapy shows how these ideas ended up in therapy rooms.

A Tree Root, a Waiter and a Keyhole

Sartre’s first novel, Nausea (1938), describes the physical side of all this. Its hero, the historian Antoine Roquentin, finds everyday things starting to feel wrong: a pebble, a beer glass, his own hand. The climax happens on a park bench, where he stares at the root of a chestnut tree and it stops being “a root”. The word falls off, and what is left is a black, knotty lump that is simply there, for no reason. The tree, the park and he himself are all, in his word, superfluous, de trop. Most people know a mild version, the word repeated until it sounds meaningless. If that moment makes you dizzy, our nothingness meme post asks why there is anything at all.

Lying to yourself about all this has a name: bad faith. Sartre’s famous example in Being and Nothingness (1943) is a café waiter whose movements are “a little too precise, a little too rapid”. He is, Sartre says, “playing at being a waiter in a café.” There is nothing wrong with being a waiter. The problem starts when you use a role to escape the fact that you are more than the role, and “I had no choice, it is my job” is the everyday version. Bad faith works the other way too, when you pretend to be pure possibility with no body and no history: “I could totally run a marathon next month, I just do not feel like it.” The opposite is authenticity, owning your choices and your limits as yours. We take the idea apart, dinosaur nuggets included, in Sartre and the true self.

Then there are other people. In the same book Sartre describes a jealous man peeping through a keyhole, completely absorbed in the scene, until he hears footsteps in the corridor and suddenly sees himself as the other would see him: a man bent over a keyhole. Other people can turn you into an object with a label, and you never fully control what they see. That is the engine of his play No Exit (1944), in which three dead strangers wait for their torturer in a hotel room in hell and slowly realise that they are each other’s punishment. Hence the line “hell is other people”, which Sartre later said meant something narrower than it sounds: “if relations with someone else are twisted, vitiated, then that other person can only be hell.” Today it has an obvious modern version, the like count. C.M. Black stays in that hotel room a little longer in Existentialism for the Edgelords.

Why You Enjoy What Everyone Enjoys

Heidegger’s Being and Time (1927) gave existentialism its most useful concept for everyday life: “the They”, das Man, the anonymous crowd that quietly decides how one lives. One has a wedding with a DJ, one watches the series everyone is talking about and has an opinion on the finale. Heidegger’s description still reads like a comment on social media: we enjoy ourselves as they enjoy themselves, we read and judge as they judge, we even find things shocking the way they find them shocking. And who are they? Nobody in particular. Everyone is the other, and no one is himself.

The They is not evil. You need shared habits to get through a day. The danger is that it is comfortable, because it takes the weight of decision off your shoulders and lets you drift for years without noticing that you never chose your life. What pulls you out, for Heidegger, is anxiety and above all the fact that you will die. Nobody can die your death for you, so nobody can live your life for you either. One honest footnote belongs here: Heidegger joined the Nazi party in 1933 and never properly reckoned with it in public. Philosophers still argue how deeply that damages his work. Nobody argues that it was fine.

Simone de Beauvoir and the Freedom of Others

The biggest worry about existentialism is that it is a fancy excuse for selfishness, and Simone de Beauvoir answered it. In The Ethics of Ambiguity (1947) she argues that the absence of a cosmic rulebook does not mean anything goes. Values do not fall from the sky, they arise between people, and my freedom is empty in a world where everyone else is treated as an object. Her formula: “to will oneself free is also to will others free.” She also corrected Camus on a point of mood. Life is not absurd but ambiguous: its meaning is never fixed, which means it always has to be won.

Two years later she turned the same tools on gender. The Second Sex (1949) contains the line usually translated as “One is not born, but rather becomes, a woman”, which is existence precedes essence aimed at everything society told women they naturally were: emotional, maternal, meant for the home. She showed how those “natural” traits are produced by upbringing, law and money, and how women are pushed into the role of the Other, defined by men instead of defining themselves. C.M. Black covers her in Objectification: Simone de Beauvoir’s feminist idea.

Forerunners, Fellow Travellers and Refusers

Three nineteenth century writers did the groundwork before the word existed. Søren Kierkegaard (1813 to 1855) is usually called the father of existentialism, which would have annoyed him, because he hated systems. Against Hegel’s grand logic of world history he asked: fine, but what am I supposed to do with my life? Truth that matters, for him, has to be lived, which is what he meant by “truth is subjectivity”, and he warned that “the crowd is untruth”. His three stages of life, the aesthetic, the ethical and the religious with its leap of faith, are explained in Kierkegaard on faith and truth. Fyodor Dostoevsky wrote the first great existentialist anti hero in Notes from Underground (1864), a bitter ex official who swears that if science ever calculated all our choices, humans would smash the calculation just to prove they are not piano keys. And Friedrich Nietzsche supplied the cosmic setting with his madman who announces that God is dead, “and we have killed him”, leaving humans to create values themselves. His attempt at an answer is the Übermensch.

In 1945 Sartre sorted the movement into Christian existentialists, such as the psychiatrist and philosopher Karl Jaspers and Gabriel Marcel, and atheists like Heidegger and himself. Beauvoir and Merleau-Ponty belong on the list, and the psychiatrist Frantz Fanon later used existentialist tools to show how colonialism damages the way people see themselves; Sartre wrote the preface to The Wretched of the Earth (1961). We have a post on Frantz Fanon too. Then there are the refusers. Heidegger rejected the existentialist reading of his work in 1946, and Albert Camus told Les Nouvelles littéraires on 15 November 1945: “No, I am not an existentialist.” He had his own philosophy, the absurd, and the difference matters.

Camus, the Absurd and the Friendship That Broke

Camus and Sartre met in 1943 at the premiere of Sartre’s play The Flies, and for a while they were the stars of Paris. Camus had just published two books. The Stranger (1942) opens with Meursault reporting that his mother died today, or maybe yesterday, he is not sure. He later shoots a man on a beach, and at his trial the prosecution spends a strange amount of time on the fact that he did not cry at his mother’s funeral. As Camus later put it, in our society any man who does not weep at his mother’s funeral runs the risk of being sentenced to death. The Myth of Sisyphus (1942) supplies the theory: the absurd is the clash between our demand for meaning and the silence of the universe, and the honest response is to keep that clash in view, with no leap into religion, no leap into utopia and no giving up. It ends with the line every meme page knows, explained in One Must Imagine Sisyphus Happy and in our guide What Is Absurdism?

The friendship ended in 1952. Camus had published The Rebel, a book against revolutionary violence, and Sartre’s magazine ran a harsh review by his protégé Francis Jeanson. Camus answered with a letter addressed to “the editor”, and Sartre’s brutal reply ended things for good. Underneath the insults was a question that still splits people: is violence acceptable if it serves a better future? Sartre came to say yes, Camus said no. Camus won the Nobel Prize in Literature in 1957 and died in a car accident in 1960, aged 46, a story with its own strange details in our Camus trolley problem meme. Sartre was offered the same prize in 1964 and turned it down, saying a writer should not allow himself to become an institution.

Existentialism, nihilism and absurdism all start from the same bad news, that the universe does not come with built-in meaning, and then go in different directions.

Camus thought existentialists cheated a little by leaping from the absurd to a new source of meaning, God for some, history or freedom for others, and he called that leap “philosophical suicide”. Existentialists could answer that his revolt is itself a meaning giving choice. The full fight is in Absurdism vs Existentialism, What Is Nihilism? and Are Absurdists Just Nihilists With Stockholm Syndrome?

Existentialism With Worse Lighting

The movement had powerful enemies, and some of their objections are still good questions. In 1948 the Vatican put all of Sartre’s works on its Index of Forbidden Books. Marxist critics said existentialism was a philosophy for middle class people who could afford to sit in cafés worrying about freedom, since a worker on a twelve hour shift is not condemned to be free in any meaningful sense. Sartre took that seriously and spent the 1950s trying to combine the two. In the 1960s the structuralists, starting with Claude Lévi-Strauss, argued that language, culture and social structures shape us far more than existentialism admits. The fair summary is that existentialism overrates how free we are and underrates how much we are shaped. It is still hard to beat as a description of what it feels like, from the inside, to have to decide.

It is also often misread. It is not “nothing matters”, which is nihilism; it says the opposite, that because nothing is decided in advance your choices matter a great deal. It is not “do whatever you want”, because Sartre argued that in choosing for yourself you sketch what you think a human being should be, and Beauvoir added that you cannot want your own freedom without wanting it for others.

The ideas show up today in places that never mention Sartre. Existential therapists such as Rollo May and Irvin Yalom work with what Yalom called the four givens of human life: death, freedom, isolation and meaninglessness. Viktor Frankl, who survived Auschwitz, wrote in Man’s Search for Meaning (1946) that everything can be taken from a man but one thing, the last of the human freedoms, to choose one’s attitude in any given set of circumstances. And every meme about staring at the ceiling at 3 a.m. is, technically, existentialism with worse lighting.

In daily life it comes down to a few small habits. Translate “I have to” into “I choose to” and see whether the sentence still feels true. When you catch yourself thinking “one should”, ask Heidegger’s question: says who? Treat anxiety as a signal pointing at a real decision. Keep facts apart from verdicts, because “I failed the exam” is facticity and “I am stupid” is a verdict you chose. And ask whether you could stand behind what you did if nobody liked it.

If you want to read further, start short. Sartre’s Existentialism Is a Humanism is about fifty pages and contains the paper knife and the student. Camus’s The Stranger takes an afternoon. Bakewell’s At the Existentialist Café (2016) is the most entertaining introduction there is. Our philosophy reading list for beginners has more, and if you are still dizzy, start with the clash Camus thought the existentialists dodged: Is absurdism just existentialism with good vibes?