What Is Existentialism? A Beginner's Guide to the Philosophy of Freedom and Meaning

Existentialism is one of the most-quoted and least-understood philosophical movements of the 20th century. Most people have heard of Jean-Paul Sartre's Being and Nothingness, Simone de Beauvoir's The Second Sex, or Albert Camus's The Myth of Sisyphus — and most can paraphrase the rough idea: human beings are free, life has no built-in meaning, you have to create your own. What gets lost in the popular summary is what existentialism actually argues, what problems it was responding to, and why it still matters in 2026.

This article walks through what existentialism really is, who the major thinkers were, what the central claims hold up to, and how the philosophy applies to a 21st-century reader who is not planning to write a 600-page book on phenomenology.

What Existentialism Actually Argues

The core claim of existentialism is often summarised in Sartre's slogan: existence precedes essence. Most things in the world are the other way around — a chair has an essence (its function as a seat) before it exists as a particular object; a knife is designed to cut before any particular knife is made. Sartre argued that human beings reverse this. We exist first; only then, through our choices and actions, do we acquire whatever essence we have. There is no human "nature" baked in at birth that we are realising. We are what we do.

This produces three consequences existentialists keep returning to.

Radical Freedom

If there is no pre-given essence, then nothing fundamental constrains who you can become. You are, in Sartre's phrase, "condemned to be free." Even refusing to choose is a choice. Even claiming you "had no option" is a choice to interpret your situation that way. The implication is uncomfortable: most of the constraints we cite as reasons we cannot change our lives are, on the existentialist view, choices we are making and disowning.

The Absurd

If life has no built-in meaning, then any meaning has to be created — by us, in the face of a universe indifferent to our choices. Camus called the gap between our hunger for meaning and the universe's silence "the absurd." His response was not despair but defiance: live anyway, make meaning anyway, and treat the act of doing so as the meaning itself. The Sisyphus essay famously ends: "One must imagine Sisyphus happy."

Authenticity

If you can choose almost anything but you are choosing in a culture that constantly pressures you toward particular roles, then the central existential challenge is authenticity — choosing in accordance with what you actually value rather than what you have been told to value. The opposite is what Sartre called mauvaise foi (bad faith) — pretending to yourself that you had no choice, or that your role determined your action, or that you are simply being what circumstances made you.

These three ideas — freedom, the absurd, authenticity — form the spine of existentialist thought. Everything else is application or argument.

The Major Thinkers

Existentialism is usually traced to a small group of writers between roughly 1840 and 1960. The thinkers below disagree with each other in important ways, but they share the basic concern with individual existence, freedom, and the construction of meaning.

Søren Kierkegaard (1813-1855)

The Danish philosopher Kierkegaard is generally regarded as the first existentialist, though the term did not exist in his lifetime. He wrote against the abstract systems of German idealism (especially Hegel) and insisted that philosophy must address the individual, in the moment of decision, with all the anxiety that real choice involves.

Kierkegaard's contribution is the leap of faith — his term for the kind of decision that cannot be justified by reason alone but must be made anyway, in full awareness of the uncertainty. His religious framing (Kierkegaard was a Christian) makes him an unusual fit with later atheist existentialists, but the structural insight survives: choice without certainty, made in the present, with full personal commitment.

Friedrich Nietzsche (1844-1900)

Nietzsche is sometimes classified as existentialist and sometimes not — he predates the formal movement and disagreed with much of what Kierkegaard wrote. But his core concerns map closely. The "death of God" line in The Gay Science (1882) frames the existentialist problem perfectly: if traditional sources of meaning have collapsed, what do we do now? Nietzsche's answer — the project of becoming who you actually are, the Übermensch — has been mis-read for a century, but the central concern with self-creation is recognisably existentialist.

Martin Heidegger (1889-1976)

Heidegger's Being and Time (1927) is the heaviest existentialist text and the most influential among professional philosophers. His central concept, Dasein (literally "being-there," roughly "human existence"), is the entity for which existence is itself a question. Heidegger added two ideas that became central to later existentialism: being-toward-death (we live in the awareness that we will end, and that awareness shapes everything) and authenticity as the project of owning our finite lives rather than fleeing into anonymous routine.

Heidegger's later association with the Nazi Party complicates his philosophical legacy and is a separate issue from the validity of his ideas. The work and the political record both have to be reckoned with.

Jean-Paul Sartre (1905-1980)

Sartre is the existentialist who made the movement famous. Being and Nothingness (1943) is the formal philosophical statement; Existentialism Is a Humanism (1946) is the accessible summary; Nausea (1938) is the novel that brought the ideas to a mass readership. Sartre's atheism turned Kierkegaard's framework upside down: if there is no God, there is no pre-given essence, and the existentialist conclusions follow.

Sartre's most-quoted line — "Hell is other people" (from the play No Exit) — is widely misunderstood. He meant that we partly experience ourselves through how others see us, and being trapped in someone else's judgment is a particular kind of hell. He did not mean other people are bad.

Simone de Beauvoir (1908-1986)

Beauvoir was Sartre's lifelong partner and one of the most rigorous existentialist thinkers in her own right. The Second Sex (1949) applied existentialist ethics to gender — arguing that "one is not born, but rather becomes, a woman," meaning that gender roles are constructed through cultural pressure rather than determined by biology, and that women's situation has historically restricted their freedom in ways men's has not.

The Ethics of Ambiguity (1947) is her most direct ethical statement. She argued — against the charge that existentialism was nihilistic — that the same freedom that opens our own lives implies a responsibility to protect the freedom of others.

Albert Camus (1913-1960)

Camus disagreed with Sartre on many issues — including the application of existentialist ethics to political violence — and famously rejected the existentialist label. But his work shares the central concerns. The Myth of Sisyphus (1942) addresses suicide as the central philosophical question (if life is meaningless, why continue?) and answers with the doctrine of revolt — keep pushing the boulder, anyway, because the alternative concedes more to absurdity than the absurd deserves.

The Stranger (1942) and The Plague (1947) are the novels. The 1957 Nobel Prize in Literature went to Camus partly for this work and partly for his journalism on the Algerian War.

What Existentialism Was Responding To

Existentialism is usually framed as a 20th-century response to specific historical conditions. Several pressures fed into it.

The collapse of religious authority. By the late 19th century, traditional religious frameworks had lost their grip on European intellectual culture. The "death of God" was a description of fact, not a normative claim. The question was what to do with the meaning-making job that had previously been outsourced to religion.

Industrial and bureaucratic life. Modern life was producing roles — clerk, factory worker, soldier, manager — that absorbed individuals into systems where personal choice felt absent. Existentialism was partly a reaction against the experience of being a cog.

The world wars. Both world wars produced widespread experiences of meaninglessness, arbitrary death, and the failure of established systems. Sartre, Camus, and Beauvoir were all active in or shaped by the French Resistance. The post-war years were the philosophical movement's peak partly because that experience was fresh.

Mass society and conformism. Heidegger's das Man (the They) and Sartre's bad faith both targeted the pressure of mass society to absorb individuals into pre-formed roles. The existentialist project of authenticity was partly a defence against this absorption.

The pressures look different in 2026, but the underlying problem of meaning-construction in a culture that does not supply ready-made meaning is largely the same.

Common Misconceptions About Existentialism

"Existentialism Says Life Is Meaningless"

This is the closest popular summary to actually being wrong. Existentialists agree there is no built-in meaning to life — meaning is not supplied by the universe. But the conclusion is that meaning must be constructed, not that it is impossible. Sartre, Camus, Beauvoir, and Kierkegaard all argued for ways of building meaningful lives. The "everything is meaningless" reading drops the second half of the argument.

"Existentialism Is Just Depression in Philosophical Clothing"

Existentialist writers do address anxiety, dread, and despair — Kierkegaard literally wrote a book called The Concept of Anxiety (1844). But they treat these as features of the human condition to be reckoned with, not as endorsements. The recommended response in most existentialist writing is engagement, action, and the construction of meaning — not withdrawal.

"Existentialism Is the Same as Nihilism"

Nihilism holds that nothing has meaning and no values are valid. Existentialism agrees that nothing has pre-given meaning and then makes the opposite move — claiming that we are responsible for creating meaning and value through our choices. Sartre explicitly framed existentialism as an answer to nihilism, not a version of it.

"Existentialism Means You Can Do Whatever You Want"

The freedom existentialists describe is uncomfortable, not liberating in the casual sense. Sartre called us "condemned to be free." Beauvoir argued that our freedom implies responsibility to others' freedom. Camus's revolt requires sustained engagement, not hedonism. The popular version that strips out the responsibility loses the philosophy.

"Heidegger and Sartre Agreed With Each Other"

They did not. Heidegger denied being an existentialist and rejected the humanist framing Sartre attached to the movement. Sartre, Camus, and Beauvoir all disagreed with each other on specific points (Sartre and Camus famously fell out over communist violence in the 1950s). The movement is best understood as a family of related positions rather than a single doctrine.

Why Existentialism Still Matters in 2026

The pressures that produced existentialism are different in detail but similar in shape today. Three current applications make the philosophy more relevant rather than less.

The fragmentation of inherited meaning. Religion, nationalism, and grand political ideologies are weaker meaning-providers in 2026 than they were when Sartre was writing. The job of constructing meaning has been pushed further onto individuals. Existentialism is the philosophical tradition with the most detailed map of how to do that work.

The automation question. Generative AI in 2026 is reshaping what work means for many people. The existentialist project — defining yourself through your choices and actions rather than through your function — gives a framework for thinking about identity when economic role becomes less stable.

Algorithmic conformism. The pressures Heidegger called das Man are amplified by social media algorithms that reward conformity to viral patterns. The existentialist insistence on authenticity — choosing in accordance with what you actually value, against the pressure to imitate — is more relevant in 2026 than it was when Sartre was complaining about Parisian café conformism.

For broader practical philosophy, see our what is stoicism guide. For applying existentialist ideas to learning and meaning-construction in daily life, our why microlearning works post touches on adjacent ground.

How to Actually Read Existentialism

Existentialist texts vary widely in difficulty. Three approaches work for a first reader.

Start With the Novels

Sartre's Nausea, Camus's The Stranger and The Plague, and Beauvoir's She Came to Stay deliver the central ideas through narrative rather than argument. They are dramatically more accessible than the philosophical texts and convey what the philosophy feels like — which matters because existentialism is partly about the experience of being a self.

Then the Accessible Essays

After the novels, move to The Myth of Sisyphus (Camus, 80 pages) and Existentialism Is a Humanism (Sartre, ~70 pages in modern editions). Both are deliberately written for non-specialists. Beauvoir's The Ethics of Ambiguity (140 pages) is the next step.

Save the Heavy Texts for Later

Being and Nothingness (Sartre), Being and Time (Heidegger), and The Second Sex (Beauvoir) are all worth reading but reward prior familiarity with the simpler texts. They are long, technical, and use philosophical vocabulary that is easier to follow with the popular essays as background. Most readers benefit from at least three months between the introductory novels and the major treatises.

Frequently Asked Questions

What is existentialism?

Existentialism is a 19th and 20th century philosophical movement that emphasises individual existence, freedom, and the construction of meaning in a universe that does not supply pre-given meaning. Its core slogan — Sartre's "existence precedes essence" — argues that human beings have no fixed nature; we become what we are through our choices. Major thinkers include Kierkegaard, Nietzsche, Heidegger, Sartre, Beauvoir, and Camus.

Who founded existentialism?

The Danish philosopher Søren Kierkegaard (1813-1855) is generally regarded as the first existentialist, though the term did not exist in his lifetime. The movement was named and popularised in 20th-century France by Jean-Paul Sartre, Simone de Beauvoir, and (informally) Albert Camus, with significant prior contributions from Friedrich Nietzsche and Martin Heidegger.

What does "existence precedes essence" mean?

"Existence precedes essence" is Sartre's slogan for the existentialist position that human beings have no pre-given nature. Unlike a chair (designed for a function before it exists) or a knife (designed to cut before any particular knife is made), human beings exist first and then acquire their essence through their choices and actions. There is no human "nature" baked in at birth that we are realising — we are what we do.

Is existentialism the same as nihilism?

No. Nihilism holds that nothing has meaning and no values are valid. Existentialism agrees that nothing has pre-given meaning but then makes the opposite move — claiming that we are responsible for creating meaning and value through our choices. Sartre framed existentialism explicitly as an answer to nihilism rather than a version of it.

What is the meaning of life according to existentialism?

Existentialism denies that life has a single built-in meaning supplied by the universe, but does not conclude that life is meaningless. Instead, meaning has to be constructed by each person through authentic engagement with their freedom — choosing what to value, taking responsibility for those choices, and acting in accordance with them. Camus called this "revolt against the absurd"; Sartre called it living without bad faith; Beauvoir called it taking up the freedom one already has.

What is bad faith in existentialism?

Bad faith (mauvaise foi in French) is Sartre's term for the act of denying your own freedom — pretending to yourself that you had no choice, that your role determined your action, that you are simply being what circumstances made you. The standard example in Being and Nothingness is a waiter who plays the role of "waiter" so thoroughly that he forgets he is choosing to play it. Bad faith is the central failure mode existentialism warns against.

Is existentialism still relevant today?

Yes — arguably more so than when Sartre was writing. The pressures that produced existentialism (the fragmentation of inherited meaning, the absorption of individuals into roles, the failure of established systems) are present in 2026 in different forms: religious and political authority is weaker, algorithmic conformism is stronger, and the automation question is reshaping what work means for many people. Existentialism remains the philosophical tradition with the most detailed map of how to construct meaning in a culture that does not supply it ready-made.

Summary

Existentialism is the philosophical movement, running from Kierkegaard in the mid-19th century through Sartre, Beauvoir, Camus, and Heidegger in the mid-20th, that emphasises individual existence, radical freedom, and the construction of meaning in a universe that does not supply pre-given meaning. Its core slogan — "existence precedes essence" — argues that human beings have no fixed nature; we become what we are through our choices. The central practical implications are that we are responsible for what we do, that the constraints we cite for our inaction are often choices we are disowning, and that an authentic life means choosing in accordance with what we actually value rather than what culture pressures us to value. The movement is widely misunderstood as nihilistic or depressive; in fact existentialists argue for engagement, action, and meaning-construction rather than withdrawal. The philosophy remains particularly relevant in 2026 because the pressures it was designed to address — fragmented inherited meaning, role absorption, conformism — are at least as strong now as they were when Sartre was writing. Start with the novels (Camus's The Stranger, Sartre's Nausea), then the accessible essays (The Myth of Sisyphus, Existentialism Is a Humanism), and save the heavy treatises for after you have the framework.