Existentialism
in a Hurry

The Whole Thing in One Page

Existentialism is what philosophy looks like once you stop pretending the universe came with instructions. Its opening move is a demolition. There is no built-in human nature, no cosmic purpose you were made to serve, no meaning stitched into reality waiting to be found. You were thrown into existence without being consulted, and nothing, no god, no tradition, no law of nature, can tell you what you are for.

The famous formulation is Sartre’s: existence precedes essence. A knife has an essence first, the purpose it was designed for, and then it exists. A human being exists first, as a bare fact, and only afterwards makes itself into something through its choices. You are not a fixed thing with a given function. You are what you do, and nothing else.

That should sound liberating, and mostly it is terrifying, which the existentialists took to be the honest reaction. If nothing determines you, you are radically free, and radical freedom means total responsibility. Every choice is yours, with no external rulebook to carry the blame. This produces a specific dread they called anxiety: the vertigo of noticing that the entire weight is on you, and always was.

Most people flee it. They pretend the choice was never theirs, hide inside roles and rules and what one is supposed to do, and tell themselves their life was handed to them. Sartre called this bad faith: lying to yourself about your own freedom to escape the burden of it.

Camus gave the predicament its sharpest image, the absurd, the collision between our hunger for meaning and a silent universe that supplies none. His response was not despair but revolt: living fully anyway.

The alternative to fleeing is authenticity. You do not find meaning. You make it, own it, and act, knowing it rests on nothing underneath.

That is the book.

Why You Should Care

You are already living out an answer to this, whether or not you have noticed. You have made choices about work, relationships, and how you spend your one finite run of time, and you have almost certainly told yourself a story in which many of those choices were not really choices. They were expected. Necessary. Just how things are. Existentialism’s claim is that this story is usually a lie, and an expensive one.

Why it matters practically: most people organise their lives around an inherited script they never examined: this is what you do after school, this is what success looks like, this is the sequence a life is supposed to follow. The script feels like reality because everyone around you is running it too. Existentialism forces the uncomfortable question of whether you chose your life or merely absorbed it. If you have been coasting on defaults, that question is either the most useful one you will ever face or the one you will spend enormous energy avoiding.

The stakes are specific: it is the difference between a life that is yours and one that happened to you. You can reach fifty having done everything correctly by external measure and discover the standard was never one you endorsed, only one you failed to question. The existentialists would say that is the real catastrophe, not failure, but a life spent executing someone else’s plan and calling it your own. Nobody sends a warning. You can sleepwalk the entire distance.

This bites harder the more freedom you have. A person with few options is constrained. A person with education, money, and choices has fewer excuses, and the modern condition hands more people more freedom than any prior era, which is precisely why the anxiety is so widespread. When the external constraints fall away, the weight of authorship lands, and most people find it unbearable. They rush to fill the vacuum with anything that will make the choices feel made for them: an ideology, a brand, a strong personality to follow, a busy schedule that leaves no room to ask why.

There is a second reason to care, harder to sell but more honest. Existentialism does not comfort you. It is close to the only major philosophy that refuses to. It does not promise the universe is secretly benevolent, that suffering is deserved, that things happen for a reason, or that meaning is out there to be discovered by the deserving. It says the reason-shaped hole in the world is real, and no one is going to fill it for you. If that is true, you want to know, because building your life on a reassurance that turns out to be false is worse than building it on an uncomfortable fact.

And the payoff is not despair, which is the standard misreading handled later. The payoff is ownership. If meaning is not found but made, then you are not a spectator waiting for your life to be validated from outside. You are the author, on the hook, but in charge. That is a heavier and freer position than the one most people occupy, and the entire philosophy is an argument for taking it up on purpose rather than backing into it by default.

The next fifty minutes are about what freedom, anxiety, absurdity, and authenticity mean, where the idea came from, and what it demands of you once you stop being able to unsee it.

The Core Ideas

1. Existence Precedes Essence

Start with the sentence the whole movement hangs on, Sartre’s: existence precedes essence. It sounds abstract and is not. Take a paper knife. Before it exists, there is a concept of it in the maker’s mind, a purpose, a set of properties it must have. The essence, what it is for, comes first, and the object is manufactured to match. Almost everything made works this way, essence then existence.

The traditional view of human beings runs on the same model. There is a human nature, fixed by God or biology or reason, that defines what a person is for and how they should live. You arrive as a specimen of a type with a built-in function, and living well means fulfilling it. Existentialism denies this outright. For a human being, the order reverses. You exist first, as a bare fact, thrown into the world without specification, and only then, through living, do you make yourself into something. There is no blueprint. The essence, if there ever is one, comes at the end, assembled from what you did, not issued at the start.

The historical event behind this is what Nietzsche meant by the death of God, and the phrase is routinely misread. It is not gleeful atheism. It is a diagnosis. Nietzsche’s point was that European civilisation had stopped believing in the God that underwrote its entire system of meaning and value, and had not yet grasped the consequences. If there is no divine author, there is no cosmic purpose, no objective moral order, no meaning built into the structure of things. The foundations are gone, and the building has not yet noticed it is standing on nothing. Nietzsche thought this was the defining crisis of the modern age, and that most people would spend enormous effort not looking at it.

That is the vacuum existentialism operates in. Strip away the given essence, the divine plan, the natural purpose, and you are left with a strange kind of being: one that has no predetermined what before it starts living. A rock is fully a rock. A dog is fully a dog. A human being is the one thing that has to decide what it is, and cannot avoid deciding, because even refusing to choose is a choice about what to be.

This is why existentialists insist you are not a fixed object. You have no essence in the way a knife does. You are a process, a project, a series of choices extended over time, and you are never finished until you are dead, at which point you become a fixed thing precisely because you can no longer choose. While alive, you are radically unfinished. Whatever you were yesterday does not bind you today. The coward can, in the next moment, act bravely; nothing in a fixed nature prevents it, because there is no fixed nature. This is either exhilarating or unbearable depending on how much you wanted the excuse.

Two clarifications, because this idea is easy to inflate into nonsense. First, it does not deny biology or circumstance. You did not choose your body, your era, your native language, or the family you were thrown into. Existentialists call these your facticity, the raw given you must work with. The claim is not that you are unconstrained. It is that within the constraints, nothing dictates what you make of them, and no situation carries its own meaning until you assign one. Second, existence preceding essence is not a licence to invent private facts. It is a claim about meaning and value, not physics. Gravity still holds. What is up for grabs is what any of it means and what you will do about it.

Everything else in the philosophy follows from this single reversal. If you have no given essence, you are free, which is idea two. And that freedom is not the gift it sounds like.

2. Condemned to Be Free

If nothing determines what you are, then you are free, and the existentialists mean this far more radically than ordinary usage. Sartre’s phrase is deliberately harsh: man is condemned to be free. Condemned, because you did not choose to exist, cannot opt out of choosing, and carry the full weight of every choice with no authority above you to appeal to. Freedom here is not a pleasant liberty. It is a sentence.

The claim is that you are choosing constantly, including in all the places you tell yourself you are not. You think your job, your relationship, your daily conduct are fixed by circumstance or obligation. Sartre’s response is that you are choosing to continue them in every moment you do not stop. The employee who says he has no choice but to go to work has choices, quitting, walking out, refusing, accepting the consequences of each. He has decided those consequences are worse than going, which is a choice. That the alternatives are unpleasant does not make them nonexistent. Even the person with a gun to their head chooses whether to comply. The range of options can be brutally narrow and the choosing never stops.

From this, total responsibility follows, and this is the part people find intolerable. If there is no given morality handed down from outside, no objective rulebook, then when you choose you cannot offload the responsibility onto God, nature, society, or your upbringing. You are the author, and there is no co-signer. Sartre pushes it further still: in choosing for yourself, you implicitly assert that this is a worthy way for a human to act, so you choose, in a sense, for everyone. Whether or not that last step convinces you, the core is hard to dodge. Strip away the external authorities and the responsibility has nowhere to go but you.

This is why existentialist freedom is not liberating in the way a self-help slogan is. Being told you can do anything sounds wonderful until you register that it means everything you do and fail to do is on you, with no excuse available. The person who wasted a decade cannot say the decade was taken from them. They spent it. The comfort of determinism, the sense that your life was shaped by forces beyond your control, is exactly what existentialism removes. It hands back the authorship and, with it, the bill.

Note what this does to the standard excuses. I am just not that kind of person becomes a description of choices you keep making, not a fixed fact about you. I had no choice becomes I chose the least bad option, which is different. My childhood made me this way becomes my past is real, but what I do with it now is still mine. Existentialism does not deny that the past shapes you. It denies that the past decides you, because a shaped thing that can still choose is not a determined thing.

There is a genuine philosophical objection here, and honesty requires flagging it. Modern science, neuroscience and behavioural genetics in particular, makes a strong case that our choices are far more constrained by biology and conditioning than Sartre allowed. His near-absolute freedom is probably overstated, and later existentialists, de Beauvoir especially, softened it into freedom within a situation rather than freedom full stop. You do not need the extreme version for the idea to bite. Even a substantially constrained freedom is enough to make the difference between authoring your life and merely explaining it away. The useful core survives the objection: wherever choice is open, it is yours, and the reflex to pretend it is not is the thing to watch.

Sartre drew a hard consequence from this and gave it a bleak name: abandonment. With no God and no given values, there is no external authority to consult and no ready-made answer to look up. You are abandoned, left to invent the values by which you will act and then to act on them without cover. His example is a student who came to him during the war, torn between leaving to join the Free French, and so fighting for a cause and avenging his brother, and staying to care for his mother, for whom he was the only support. Every ethical system Sartre could name gave conflicting or useless advice; Christian love, Kantian duty, and utilitarian calculation each pointed a different way or fell silent. In the end, he told the young man, you are free, so choose, meaning invent. There was no sign to read and no rule that fit. The student had to pick the principle by picking the act, which is the situation, stripped of its wartime drama, that everyone is in all the time.

3. Anxiety

The correct emotional response to all this, the existentialists thought, is not calm. It is a specific dread they called anxiety, or angst, and they treated it not as a disorder to be medicated away but as a moment of clarity, the mind registering its own freedom accurately for once.

Kierkegaard, writing in the 1840s and the true origin of the tradition, gave it the sharpest image: anxiety is the dizziness of freedom. Stand at the edge of a cliff and you feel two things. One is the fear of falling. The other, stranger and more disturbing, is the awareness that nothing stops you from throwing yourself off. Not that you want to. Simply that you could, that the possibility is yours, and that only your own choice stands between you and the drop. That vertigo, the sensation of your own untethered freedom, is anxiety. It is not fear of any particular thing. Fear has an object, a snake, a deadline, a diagnosis. Anxiety has no object, or rather its object is nothing, the empty space of possibility where a determined nature should be and is not.

Heidegger developed this in Being and Time. For him, everyday fear is always fear of something specific inside the world. Anxiety is different in kind: it is what surfaces when the whole familiar world briefly loses its meaning and you confront the bare fact of your own existence with no comforting structure to hide it. In anxiety, the props fall away, the roles and routines that normally tell you who you are stop working, and you are left facing the naked question of your own being. This is unpleasant, which is why people avoid it, but Heidegger thought it was disclosive: it shows you something true that everyday busyness keeps hidden, that your existence is your own and unfounded. A warning before going further: Heidegger’s full account is dense and technical, embedded in an entire ontology this book does not attempt. I am giving you the usable core and deliberately not the machinery.

The crucial move, shared across the tradition, is the refusal to treat this dread as merely pathological. Modern culture tends to classify anxiety as a malfunction, something wrong with you to be fixed. The existentialists allowed that much anxiety is indeed clinical and treatable, and did not romanticise suffering. But they identified a residue that is not a disorder at all: the accurate perception that your life is unfounded, unscripted, and entirely on you. That form of anxiety is not a sign something has gone wrong. It is a sign you have seen your situation clearly. Medicating it away entirely, if that were even possible, would mean sedating yourself against a truth.

What you do with the dread is the fork in the road. You can flee it, which is the next idea, bad faith, the vast machinery of self-deception people build to avoid ever feeling the vertigo. Or you can go through it and out the other side, using the clarity it offers to take up your freedom rather than hide from it, which is authenticity, later. Anxiety is the hinge. It is the moment the truth of your condition becomes available, and almost everything a person does next is either an honest response to it or an elaborate evasion. The existentialists’ wager is that the honest response, though harder, is the only one that leads anywhere worth going.

4. Bad Faith

Given how uncomfortable freedom and its anxiety are, the obvious human move is to escape them, and Sartre gave the escape a name: bad faith. It is the central concept of his practical philosophy and the one most immediately useful for looking at your own life. Bad faith is lying to yourself, specifically lying to yourself about your own freedom in order to avoid the burden of it. It is not ordinary lying, where you know the truth and conceal it from someone else. It is the stranger act of being both the deceiver and the deceived, hiding a truth from yourself that at some level you know.

Sartre’s famous illustration is a cafe waiter who is a little too much the waiter. His movements are slightly exaggerated, precise, performed. He is playing at being a waiter the way a child plays a role, so completely that he tries to become identical with the function, to be a waiter the way an inkwell is an inkwell, fully and without remainder. Why? Because if he is only a waiter, essentially and completely, then he is relieved of the anxiety of being a free person who is currently choosing to wait tables and could choose otherwise. He hides in the role. The role becomes a place to put down the unbearable weight of being free.

This is everywhere once you see it. The person who says I can’t, it’s just who I am, is using a claimed fixed nature to avoid admitting they are choosing. The person who says I had no choice is disowning a decision they made. The person who buries themselves in duty, in what one is supposed to do, in the expectations of their role as parent or professional or citizen, and treats those expectations as external commands rather than things they are choosing to obey, is in bad faith. So is the person who treats their past as an alibi, or their feelings as forces that happen to them rather than reactions they are in some part sustaining. In each case the structure is identical: a free being pretending to be an unfree thing, to escape the responsibility that freedom carries.

Bad faith works by exploiting a real duality in human existence. You are, at once, a facticity, a set of given facts, a body, a history, a situation, and a freedom, a capacity to transcend and reinterpret those facts. Bad faith collapses one into the other. Sometimes it denies the freedom and hides entirely in the facticity: I am just this, fixed, determined, not responsible. Sometimes it denies the facticity and pretends to a freedom untethered from any reality: the person who refuses to acknowledge real constraints and consequences. Honesty, good faith, means holding both at once: I am situated, shaped, constrained, and within that I am still choosing and responsible. Most self-deception is the refusal to hold both.

The uncomfortable implication is that a great deal of ordinary, respectable, well-adjusted life is bad faith. The person who followed the script perfectly, who did what was expected at each stage and never asked whether they endorsed it, has arguably spent their life fleeing their own freedom into a set of roles. Sartre is not saying roles are bad or that you should abandon your obligations. He is saying that pretending your obligations were imposed rather than chosen, that your life merely happened to you, is a lie, and a corrosive one, because it forfeits the one thing that could make the life yours. Bad faith is comfortable. That is the entire problem with it.

5. The Absurd

Camus approached the same vacuum from a different angle and gave it its most vivid name: the absurd. Note at the outset that Camus rejected the existentialist label and considered himself separate from Sartre’s camp, a dispute the myths section returns to. But the problem he worked on is the same one, and no account of this territory can leave him out.

The absurd, for Camus, is not a property of the universe alone or of human beings alone. It is a relationship, a collision between two things. On one side is the human demand for meaning, our deep, apparently ineradicable need for the world to make sense, to have purpose, order, and reasons. On the other is the universe, which is silent, indifferent, and supplies none of that. The absurd is the confrontation between the two: a meaning-hungry creature in a meaningless world, unable to stop wanting an answer the world will never give. Neither side is absurd by itself. The absurd is born in the meeting.

Camus opens The Myth of Sisyphus with a deliberately shocking claim: the only truly serious philosophical question is suicide. He means it as the sharpest possible statement of the problem. If life has no given meaning, if the universe is indifferent and our craving for significance is doomed, then the honest question is whether life is worth living at all. His entire book is an attempt to answer it without cheating, and cheating, for Camus, includes both literal suicide and what he calls philosophical suicide: the leap to a comforting belief, religious or ideological, that pretends to dissolve the absurd by supplying the meaning the universe withholds. He regarded that leap, including Kierkegaard’s leap of faith, as an evasion, a refusal to hold the tension honestly.

His answer is neither suicide nor the leap. It is revolt. You keep the absurd fully in view, refuse every false consolation, and live anyway, in defiance. The image is Sisyphus, condemned by the gods to roll a boulder up a hill forever, watch it roll back down, and descend to begin again, for eternity, with nothing achieved. This is a portrait of a meaningless existence at its starkest, labour that accomplishes nothing, repeated without end. And Camus makes the startling move of declaring that we must imagine Sisyphus happy. In the moment of walking back down the hill, conscious of his fate and scorning it, Sisyphus is superior to his punishment. The rock is his. The struggle itself, undertaken with full awareness and without appeal to any promise of reward, is enough to fill a life. Meaning is not received. It is generated in the defiant living.

The practical content of Camus’s revolt is a kind of lucid, passionate engagement with life for its own sake, freed from the demand that it add up to something cosmically. You stop waiting for life to justify itself and you live it intensely anyway, drinking in experience, acting, loving, creating, precisely because it is finite and unbacked by any guarantee. There is a clarity in this that the more systematic existentialists sometimes lack. Camus is not building a philosophy of freedom and responsibility so much as answering a single question, is life worth living without inherent meaning, with a hard-won yes. The absurd is not a reason to despair. It is a fact to be lived with open eyes, and the living, done in full view of the silence, is the whole point.

Camus drew three things out of living the absurd rather than fleeing it. The first is revolt, the constant refusal to be reconciled, keeping the tension alive instead of dissolving it with a comforting story. The second is freedom, of a particular kind: once you stop demanding that your life conform to an external purpose, you are released from the tyranny of that purpose and free to live for its own sake. The third is passion, a greater intensity of living, since the absurd person, having given up on quality of cosmic meaning, goes instead for quantity and depth of experience, more life, more fully felt, precisely because there is no next world to save it up for. Revolt, freedom, passion. Not resignation, but a heightened, defiant appetite for a life you have stopped asking to justify itself.

6. Death and Authenticity

Existentialism takes death more seriously than almost any other philosophy, and not as a morbid preoccupation. Death is the fact that makes the whole problem urgent, and confronting it honestly is, for several of these thinkers, the doorway to living authentically.

Heidegger’s term is being-toward-death, and the idea, stripped of his difficult apparatus, is this. Death is not merely an event at the end of life, out there in the future, that happens to other people. It is a permanent structural feature of your existence right now: you are the kind of being that is always going to die, whose time is finite and running, and this shapes everything whether you attend to it or not. Most of the time you flee this. Heidegger describes how we hide inside what he calls das Man, the they, the anonymous everyone: one dies eventually, people die, death is a general fact about the population, kept safely impersonal. This is an evasion. It converts your death, the one certainty that is absolutely and non-transferably yours, into a vague statistical event that happens to others. Authentic being-toward-death means dropping the evasion and owning your own mortality as yours, finite, certain, and yours alone, which paradoxically is what frees you to live. Once you grasp that your time is limited and unrepeatable, the borrowed priorities of the anonymous everyone lose their grip, and the question of what you will do with your finite existence becomes real. The reminder again: this is the usable distillate of Heidegger, not his full account, which is far more intricate and which I am deliberately not reproducing.

Authenticity is the positive ideal the whole tradition points at, though the thinkers describe it differently. The shared core is this: to live authentically is to own your existence, to face your freedom, your finitude, and the absence of any given meaning honestly, and to choose and act from that clear-eyed position rather than fleeing into the roles, scripts, and consolations that let you avoid it. The inauthentic life is the life of the anonymous everyone: doing what one does, wanting what one is supposed to want, running the inherited program without ever asking whether it is yours. The authentic life is not necessarily different in its outward content, you might end up a parent with a job much like anyone else’s, but it is inhabited differently, chosen rather than absorbed, owned rather than defaulted into.

Two things authenticity is not, because both misreadings are common. It is not the modern notion of being true to yourself, finding your authentic feelings and expressing them, because that assumes a fixed inner self waiting to be discovered, which is exactly what existentialism denies. There is no pre-existing true self to be true to. You create the self through choosing; authenticity is owning the creation, not uncovering a hidden essence. And it is not a demand to be dramatic, rebellious, or unconventional. You can be authentically conventional, if you have examined the conventional life and chosen it as yours. Authenticity is about the ownership of the choice, not its content. Kierkegaard, at the origin of all this, framed it as becoming a self, a task you undertake, not a thing you are given, and one most people never seriously attempt.

7. Freedom and Other People

The final piece corrects a caricature: that existentialism is a philosophy of the isolated individual, alone with their choices. Other people are, in fact, central to it, and this is where the tradition splits in an important way, and where Simone de Beauvoir does the work the others left undone.

Sartre’s account of other people is famously bleak. In Being and Nothingness he analyses the look, the experience of being seen by another person. When you are alone, you are the free centre of your own world, a pure subject viewing everything. Then someone looks at you, and something inverts. You become an object in their world, fixed by their gaze, judged, categorised. Caught doing something shameful, you feel it directly: under the other’s eyes you are turned into a thing, the person who did that, defined from outside. For Sartre, this generates a permanent tension. Each consciousness is trying to be the free subject, and every encounter with another involves a struggle over who is subject and who is object. This is the background to his most quoted line, from the play No Exit: hell is other people. The line is routinely misread as simple misanthropy. What Sartre meant is more precise: other people can trap you in an identity, can make you an object in ways you cannot fully control, and living perpetually under the judging gaze of others, letting their view of you define you, is a kind of hell you can fall into.

De Beauvoir took existentialist freedom and did what Sartre never adequately did with it: built an ethics from it, and applied it to real, unequal life. Her move in The Ethics of Ambiguity is to argue that because my freedom is entangled with the freedom of others, I cannot will my own freedom coherently without willing theirs too. Genuine freedom is not the lone individual against the world; it is intersubjective, realised with and through other free beings, which gives existentialism the moral dimension it is often accused of lacking. Her larger achievement is The Second Sex, which is applied existentialism of the first rank. Her thesis, one is not born, but rather becomes, a woman, is existence precedes essence turned into a social analysis: there is no fixed female essence, femininity is not a given nature but a situation constructed and imposed, and women have been cast as the Other, the object to man’s subject, denied the full free subjecthood existentialism grants everyone. It is the single most consequential application of the philosophy, and it demonstrates the point better than any abstract argument: if there is no given human essence, then the natures used to justify how people are treated are not natural at all. They are constructions, and constructions can be contested.

This also supplies the reply to the charge that existentialism is mere self-absorption. The freedom it hands you is not a permit to do as you please in isolation. It arrives entangled with everyone else’s, and de Beauvoir’s insistence on that is what turns a philosophy of individual authenticity into one that can carry an ethics and a politics. Your freedom and the other person’s are not in a zero-sum war, whatever Sartre’s darker moods suggested. They stand or fall together.

How It Actually Works

Section 3 gave you the ideas as a set. This section explains where they came from, why they arrived when they did, and the deeper structure underneath them. Existentialism is not a system with founding axioms, so understanding it means understanding the historical pressure that produced it and the method its thinkers shared.

The problem it was a response to

Existentialism is best understood as a reaction to a specific crisis, one that built over the nineteenth century and detonated in the twentieth. For most of Western history, meaning had a guarantor. A person’s purpose, values, and place were underwritten by a cosmic order, usually God, sometimes a rational structure of the universe standing in for God. You did not have to invent the meaning of your life because the framework supplied it. The question was how to live rightly within a given order, not whether there was one.

Two developments demolished this. The first was the long erosion of religious belief as the organising centre of Western life, driven by science, the Enlightenment, and industrial upheaval. This is what Nietzsche’s death of God names: not a metaphysical event but a cultural one, the point at which the God-shaped framework stopped functioning as the foundation of meaning, even for many who still nominally believed. The second was the discovery, deepening through the same period, of just how contingent and indifferent the universe is, an immense, ancient, purposeless physical process that did not have humans in mind and answers to no moral order.

The result was a vacuum where the guarantor had been. If there is no God and no built-in cosmic purpose, the traditional source of meaning and value is gone, and the question is no longer how to live within a given order but whether any order exists and what to do if it does not. Existentialism is the philosophy that takes this vacuum as its starting point and refuses to paper over it. That is the thread connecting figures who otherwise disagree profoundly: they all begin after the collapse of the guarantor, and treat the individual’s confrontation with a meaningless universe as the primary philosophical fact.

This also explains the split that runs through the whole tradition, between religious and atheistic existentialism. Both start from the same vacuum. They diverge on the response. The atheists, Sartre, Camus, Nietzsche before them, accept the absence of God and build entirely within it: meaning is human-made or it does not exist. The religious existentialists, Kierkegaard first and foremost, later Jaspers and Marcel, accept the same collapse of rational, given meaning but respond with a leap of faith, a passionate, non-rational commitment to God made precisely because it cannot be justified by reason. What unites them as existentialists is not the conclusion but the starting point and the method: the individual, alone, facing a situation reason cannot resolve, forced to commit without guarantees. Kierkegaard leaps toward God; Sartre refuses; both agree that the leap cannot be grounded in objective certainty, and that the individual must choose in the dark.

The line of development

The tradition has a reasonably clear genealogy, and knowing the order clarifies the ideas.

Kierkegaard, a Danish writer of the 1840s, is the origin, though the label did not exist in his lifetime. Writing against the vast rational system of Hegel, which claimed to explain all of reality as the unfolding of reason, Kierkegaard insisted that no abstract system could capture the reality of an existing individual, the actual, single, choosing person facing their own life. His targets, the crowd as a source of untruth, the anxiety of freedom, the leap of faith, the demand to become a genuine self rather than a cog in a system, set the entire agenda. He was a devout Christian, which is often forgotten, and his existentialism was in the service of a radical, individual faith, not against it.

Nietzsche, writing in the 1880s and independently, supplied the other precursor and the atheistic pole. Where Kierkegaard confronted the individual with God, Nietzsche confronted them with God’s absence. He diagnosed the death of God, warned that its consequence would be nihilism, the collapse into meaninglessness once the old values lost their foundation, and proposed a response: the revaluation of values, the creation of new, life-affirming values by strong individuals who could face the void without flinching. His work is the bridge between the collapse of religious meaning and the twentieth-century project of making meaning without a god. Both precursors, crucially, were doing something other philosophers were not: writing about existence as lived from the inside, in anxiety, despair, and commitment, rather than constructing impersonal theories.

The twentieth century turned this into a movement, and the hinge was phenomenology. Edmund Husserl developed a method for describing the structures of lived experience, of how the world presents itself to consciousness, rather than theorising about reality abstractly. This gave the existential themes a rigorous method. Heidegger, Husserl’s student, fused the two in Being and Time, published in 1927, applying phenomenological description to human existence itself, which he called Dasein, being-there. His analysis of thrownness, anxiety, everydayness, das Man, and being-toward-death is the technical backbone much of later existentialism draws on, even where it does not follow his ontology. A necessary flag: Heidegger did not accept the existentialist label, his project was the meaning of being in general, not a philosophy of human freedom, and his later political record, active support for Nazism, is a serious matter that the myths section addresses rather than skips.

Sartre is where it became existentialism, a public movement with a name. Encountering phenomenology in the 1930s and Heidegger’s work soon after, he built the systematic atheistic version in Being and Nothingness in 1943 and then, crucially, popularised it. His 1945 lecture Existentialism is a Humanism made it a cultural phenomenon in postwar France and beyond. Sartre is the reason the word means what it means, and also, by his own later admission, the source of some oversimplifications: the lecture he made famous he subsequently regarded as too crude. Around and with him, Simone de Beauvoir built the ethics and the most important applications, and Albert Camus, adjacent and eventually estranged, worked the absurd. The postwar moment, a Europe that had just watched civilisation produce industrial slaughter, was fertile ground: the old assurances about progress, reason, and meaning looked naive, and a philosophy that started from the void and the individual’s responsibility within it spoke directly to the condition.

What the two precursors built

Both precursors left more than a diagnosis, and their constructive ideas are worth knowing, because they are the first serious attempts to build meaning after the collapse. Kierkegaard mapped how a person might move toward becoming a self, in three stages of existence. The aesthetic life is lived for pleasure, novelty, and interest, flitting between experiences to keep boredom at bay; its flaw is that it has no centre and eventually sinks into despair. The ethical life commits, takes on duty, work, marriage, responsibility, and lives by shared moral principles; it is sturdier, but Kierkegaard thought it still could not resolve the individual’s relationship to their own existence. The religious life is the leap beyond both, a passionate, individual commitment made without rational guarantee, his image for which is Abraham, willing to sacrifice his son on nothing but faith, the knight of faith who acts on a certainty reason cannot supply. You need not share the Christianity to see the shape: a movement from living for sensation, to living by rules, to staking everything on a commitment you cannot justify from outside.

Nietzsche built the other pole. If values are made rather than found, the task is to make life-affirming ones, and his name for the person who can is the Ubermensch, the overman, not a master race, whatever his sister and the Nazis later did with the term, but an individual who creates their own values and stands behind them without a god to underwrite them. His test for whether you have truly affirmed life is the eternal recurrence, posed in The Gay Science as a thought experiment: a demon tells you that you will live this exact life, every joy and every agony, in the same order, over and over for eternity. Do you collapse in horror, or could you say yes, and mean it? To will the eternal return, to want your life so completely you would take it again without end, is his picture of the highest health. Beneath all of it he placed the will to power, his contested claim that the deepest drive in living things is not survival or pleasure but the expansion of their own strength. You can reject the metaphysics and still feel the force of the test.

The deeper machinery: phenomenology and lived experience

Underneath the dramatic themes sits a methodological commitment that distinguishes existentialism from most philosophy, and it is worth grasping because it explains why the philosophy feels different in kind.

Traditional philosophy tends to approach human beings from the outside, as objects to be explained, and to seek general, abstract truths: what is the human essence, what are the universal laws of mind, what is the good in general. Existentialism, following the phenomenological method, reverses this. It starts from the inside, from existence as lived and experienced by a particular person, and treats that first-person reality as primary rather than as a messy surface to be explained away. The technical slogan is that it prioritises the subjective, not in the sense of mere opinion, but in the sense that the lived, first-person standpoint is where the real philosophical action is, because that is where choice, meaning, and existence happen.

This is why existentialists write the way they do, in novels, plays, aphorisms, and dense description rather than only in formal argument. It is not decoration. If the target is existence as lived, then a novel that puts you inside a character’s confrontation with meaninglessness can do genuine philosophical work that an abstract syllogism cannot, because it conveys the texture of the experience rather than a proposition about it. Sartre and Camus wrote major novels and plays alongside their treatises deliberately. Kierkegaard wrote under a battery of pseudonyms, each embodying a different existential stance, so that you encounter the positions as lived possibilities rather than doctrines. The form follows from the method: to describe existence from the inside, you often have to show it, not just assert it.

The concept that anchors the method is being-in-the-world, Heidegger’s corrective to a long philosophical error. Since Descartes, philosophy had tended to picture the human being as a mind, a detached thinking subject, sitting inside a body and looking out at an external world of objects, with the great problem being how the inner mind can know the outer world. Heidegger rejected the whole picture. You are not a detached mind observing a world you are separate from. You are always already thrown into a world, entangled with it, acting in it, caring about things in it, before any detached observation begins. Existence is not first thinking and then acting; it is first being-in-the-world, practically engaged, and reflection comes later and secondarily. This dissolves the old mind-world gap by denying the separation it assumed. It matters for the ethics because it means you are never a neutral spectator choosing from outside your life. You are always already in it, situated, committed, having to act.

Thrownness and facticity: the limits on freedom

The machinery includes a crucial counterweight to the freedom that dominates the popular image, and getting this right corrects the most common distortion of the philosophy.

Heidegger’s term is thrownness. You did not choose to exist, and you did not choose the basic conditions into which you were flung: the era, the country, the language, the body, the family, the historical situation, the genetic hand. You woke up already underway, already someone, in a world already structured, with a past you did not author. This is the given, and Sartre’s term for it is facticity, the totality of the concrete facts about your situation that you did not choose and cannot wish away.

The reason this matters is that it blocks the lazy reading of existentialism as you are totally free and can be anything. You cannot. You are free only ever within a situation you did not choose. The person born into poverty, or illness, or a particular century, faces real, non-negotiable constraints. What existentialism claims is not that these constraints vanish, but that they never fully determine the meaning you make of them or what you do next. Facticity is the raw material; freedom is what you do with it. The two are always in play together, and any account that drops one falsifies the philosophy. Drop facticity and you get a naive fantasy of limitless self-creation. Drop freedom and you get determinism. The whole view lives in the tension between them: a situated freedom, thrown into conditions it did not pick, responsible for what it makes of them anyway.

De Beauvoir sharpened this into the concept of situation, and it is her refinement, more than Sartre’s early formulations, that represents the mature position. Your freedom is always concretely situated, conditioned by your body, your social position, your relationships, the material facts of your life. This is not a retreat from freedom but a realistic account of it, and it is what makes the philosophy applicable to actual unequal lives rather than to an abstract, unencumbered chooser. The freedom of a woman in 1949, or a colonised subject, or a poor person, is real but heavily conditioned by a situation others built, and any honest existentialism has to reckon with that rather than pretend everyone chooses from the same starting line.

What happened to it

Existentialism as a named movement had a steep rise and a real decline, and the shape of that rounds out the picture. Its peak was the two decades after the Second World War, when it was the most fashionable philosophy in the West, Sartre a global celebrity, the Left Bank cafes a tourist idea. Then it faded, for several reasons. Structuralism and later post-structuralism displaced it in French intellectual life, attacking its central assumption of a free, self-authoring subject and insisting that language, power, and unconscious structure shape us far more than existentialist freedom allowed. Sartre’s own attempt to fuse existentialism with Marxism satisfied few. And the label came to feel dated, welded to a specific postwar mood.

The ideas did not die, though; they dispersed, which is a different fate. Existentialist themes were absorbed so thoroughly that they stopped needing the name. Existential and humanistic psychotherapy, the work of Rollo May, Viktor Frankl, and Irvin Yalom, took the confrontation with freedom, death, isolation, and meaning and turned it into clinical practice still in use. De Beauvoir’s The Second Sex seeded second-wave feminism. And the broad modern assumption that you are responsible for authoring your own life, choosing your own values and finding your own meaning rather than receiving them from church, class, or tradition, is now so ordinary in the West that most people hold it without knowing where it came from. Existentialism partly won by dissolving into common sense.

Why the pieces hold together

Assemble the machinery and the logic of the whole is visible. Start with the collapse of the guarantor: no God, no cosmic purpose, no given essence. From that, existence precedes essence follows directly, there is no blueprint, so the human being must make itself. From the absence of a blueprint, radical freedom follows, nothing dictates what you become. From freedom, total responsibility follows, with no external authority, the choice and its weight are yours. The honest emotional registration of that responsibility is anxiety. The commonest response to anxiety is bad faith, fleeing the freedom by pretending to be a determined thing. The alternative, going through the anxiety rather than around it, is authenticity, owning the freedom, the finitude, and the absence of guarantees, and choosing anyway. Thrownness and facticity keep the whole thing honest by insisting this all happens within unchosen limits. And because your freedom is entangled with others’, the individual account opens onto an ethics.

It is not a system in the way Hegel’s is, with everything deduced from a first principle. But it is not a random collection of moods either. It is a connected response to a single historical situation, the situation of having to live meaningfully in a universe that provides no meaning, and each concept is a different facet of that one predicament. That is the coherence to hold onto: not a doctrine, but a sustained, many-angled answer to the question of how to exist once you can no longer pretend the universe will answer it for you.

What People Get Wrong

“Existentialism is depressing”

The dominant misread, and it confuses the diagnosis with the mood. Yes, the philosophy starts from meaninglessness, death, and anxiety, which sounds bleak. But its conclusion is the opposite of despair: because meaning is not given, you get to make it, and your life is yours to author. That is an empowering claim, not a defeated one. Sartre insisted existentialism was an optimism, a philosophy of action and possibility. Camus’s whole point was that you can be happy in an absurd universe. The bleakness is in the honest starting premises; the payoff is ownership. Mistaking the unflinching diagnosis for the overall verdict is like calling medicine morbid because it studies disease.

The mood confusion has a specific source: existentialist writing is honest about states other philosophies tidy away, dread, nausea, despair, and readers assume a philosophy that names those must be recommending them as the destination. It is the reverse. Naming the dread accurately is the precondition for getting past it. A philosophy that pretended the anxiety was not there could offer only a brittle comfort; one that looks straight at it can offer a durable one. The bleak reputation is the price of that honesty, not evidence of a bleak conclusion.

“It means life is meaningless, so nothing matters”

This collapses a careful distinction. Existentialism denies cosmic or given meaning, meaning built into the universe from outside. It does not deny meaning as such. The claim is that meaning is created, not found: by your commitments, projects, relationships, and choices. Nothing matters inherently, and things matter enormously once you commit to them. In fact the position raises the stakes rather than lowering them, because if the universe does not supply significance, then what you do is the only source of it, so your choices carry more weight, not less. “Nothing matters” is nihilism, and existentialism is largely an argument against nihilism, an attempt to answer it, not an example of it.

The practical difference shows in how a nihilist and an existentialist spend a Tuesday. The nihilist reasons that since nothing matters inherently, nothing is worth doing, and drifts toward paralysis. The existentialist reasons that since nothing matters inherently, what you commit to is the whole source of what matters, and so commits, hard, and lives as though the commitment were load-bearing, because it now is. Same premise, opposite life. Existentialism takes the nihilist’s starting point and refuses the nihilist’s conclusion, which is most of what it is for.

“It’s just do whatever you want”

The reverse error: mistaking radical freedom for a licence for hedonism or caprice. It is nearly the opposite. Existentialism couples freedom with total responsibility and heavy moral seriousness. You are answerable for every choice with no excuses available, which is a far more demanding position than following external rules you can blame when they fail. Sartre’s freedom is a burden, not a party. And de Beauvoir built an explicit ethics from it: because your freedom is bound up with others’, authentic freedom entails respecting theirs, which rules out treating people as mere means. “Do whatever you want” is what the philosophy calls out as bad faith when the wanting is unexamined, not what it recommends.

The confusion trades on the word freedom, which in ordinary use means being unconstrained, permitted, free to indulge. Existentialist freedom is nearly the opposite in feel: the inescapable fact that you must choose and answer for it, a condition you are stuck with rather than a permission you enjoy. Nobody experiences Sartre’s freedom as a licence to party. They experience it, if they let themselves feel it at all, as a weight. Reading it as hedonism is possible only by quietly dropping the responsibility that Sartre welds to it.

“Camus was an existentialist”

He said he was not, repeatedly, and the distinction is real, not pedantic. Camus rejected the label and distanced himself from Sartre’s systematic philosophy of freedom and essence. He was interested in one question, how to live given the absurd, and considered himself a moralist in the French tradition rather than an existentialist. The two men also split publicly and bitterly in 1952, over politics as much as philosophy: Camus’s The Rebel rejected revolutionary violence and the Soviet project, Sartre’s circle savaged the book in his journal, and the friendship ended. Camus is covered in any treatment of this territory because he works the same problem, but calling him an existentialist flatly, without the caveat, misrepresents him. He is adjacent, not inside.

“Nietzsche was an existentialist,” and the Nazi smear

Two errors bundled together. First, Nietzsche predates the movement and never used the term; he is a precursor whose diagnosis of the death of God and nihilism set up the problem, not a member of a school that formed after his collapse. Calling him an existentialist is a backward projection, useful but loose. Second, the persistent association of Nietzsche with Nazism is a distortion, largely manufactured after his death by his sister Elisabeth, an antisemite and later Nazi sympathiser who edited and weaponised his unpublished notes. Nietzsche himself despised antisemitism, German nationalism, and mass politics, and broke with Wagner partly over it. His concepts were later appropriated by people he would have held in contempt. The ideas can be criticised on their own terms; the Nazi label is a slander of provenance.

“Heidegger’s philosophy is Nazi philosophy”

The harder case, because unlike Nietzsche, Heidegger was in fact a Nazi: he joined the party in 1933, served as a university rector implementing its policies, and his later published notebooks contain antisemitism. This is not a smear; it is his record, and it should not be minimised. The contested question is how far the philosophy is contaminated by the politics. Positions range from the work is fatally compromised throughout to Being and Time predates his Nazism and stands somewhat independently. There is no consensus, and anyone offering you a clean answer is selling one. The honest handling, and the one this book takes: use his usable concepts with attribution, do not pretend the man was other than he was, and treat the relationship between the thought and the politics as an open, serious problem rather than a settled verdict either way.

“It’s a self-indulgent philosophy of isolated individuals”

The charge is that existentialism is navel-gazing, all about my authenticity, my freedom, my meaning, with no room for society or ethics. It has some surface plausibility, Sartre’s early work is individual-focused and his hell is other people reputation does not help, but it is largely wrong. De Beauvoir built a full ethics and, in The Second Sex, one of the twentieth century’s most consequential works of social and political analysis, directly from existentialist premises. Sartre himself moved toward Marxism and political engagement. The core idea, that freedom is entangled with others’ freedom, is inherently social. Existentialism produced serious ethics, feminism, and political thought; the solipsistic caricature ignores half the tradition, and the more important half for anyone who wants to live by it.

Use It

Existentialism is not a set of techniques. You cannot practise it the way you practise Stoic exercises or Buddhist meditation. What it gives you is a way of seeing your own life that is hard to unsee once you have it, and a standard to hold your choices against. This is what it changes in practice.

The lens: catch yourself saying “I have to”

The single most useful habit the philosophy installs is noticing the phrase, in your own speech and thought. I have to go to work. I can’t leave. I have no choice. This is what I’m supposed to do. Nearly every time, it is false. You do not have to; you are choosing to, because the alternatives are worse or frightening or costly. That is a real reason, but it is a choice with reasons, not an absence of choice.

The correction is small and destabilising: replace I have to with I am choosing to, because. I am choosing to stay in this job, because I value the security more than the freedom right now. I am choosing to stay in this relationship, because I judge it worth the frustrations. Said honestly, this does two things. It returns the authorship to you, which is uncomfortable, because now the life is yours and not something inflicted on you. And it exposes the choices you have been pretending not to make, some of which you might, on inspection, decide to make differently. Most people never run this check because the I have to is load-bearing: it protects them from the responsibility. That is exactly why it is worth running.

The lens: the script is not yours until you check it

Existentialism’s most practical use is as a tool against the inherited default. Everyone absorbs a script, the sequence a life is supposed to follow, what counts as success, what you are supposed to want. Most of it was installed before you could evaluate it, by family, class, era, and the ambient assumptions of your surroundings. The philosophy asks one question of every major element: did you choose this, or did you absorb it?

This is not an instruction to reject the script. That would be its own conformity, rebellion for its own sake, which is just the script inverted. It is an instruction to audit it. Some of what you inherited, you would choose again on examination; keep it, but now as yours. Some of it you are running purely because you never questioned it, and it does not survive the question. The point is that an unexamined life is not authentically yours even if it happens to be a good life, because you never authored it. You defaulted into it. Authenticity is not about the content of the choices; it is about whether you made them.

A concrete version: take one large feature of your life you have never seriously questioned, the career track, the assumption that you will own rather than rent, the plan to have children or not, the politics or religion you inherited, and ask honestly whether you chose it or absorbed it. Not in order to overturn it, most of it may survive, but to convert it from a default into a decision. The parts that survive the question you now hold as yours, which changes how it feels to live them. The parts that do not survive were quietly costing you a life you never agreed to.

The lens: your anxiety might be accurate

This one is useful and cuts against the prevailing culture. Modern life treats anxiety as a malfunction to be eliminated, and much of it is treatable and worth treating. But existentialism identifies a specific form that is not a disorder: the dread that surfaces when you confront the fact that your life is unfounded, finite, and entirely on you. That anxiety is not a sign something is broken. It is a sign you are seeing your situation clearly.

The practical implication is to distinguish two things before reaching for the off switch. Some anxiety is noise, treat it. But some is signal: it is telling you that you are living in bad faith, executing a life you did not choose, avoiding a decision you know you need to make. That kind does not want medicating; it wants acting on. The vertigo you feel contemplating a major change is not necessarily a warning that the change is wrong. It may be the accurate sensation of your own freedom, which is supposed to feel like that. Learning to read which is which is one of the more valuable things the philosophy offers.

The lens: mortality clarifies priorities

Being-toward-death, made practical, is a filter. You are going to die, your time is finite and running, and most people keep this abstract to avoid its force. Brought into focus, it sorts the important from the borrowed priorities you are carrying because everyone else carries them. The test is direct: knowing your time is limited and unrepeatable, is this how you are choosing to spend a portion of it? Applied honestly, it dissolves a surprising amount of what fills a life, the status games, the obligations you never endorsed, the deferral of what matters to a someday that is not guaranteed. This is not morbid. It is the opposite: death taken seriously is what makes life urgent enough to inhabit.

The filter has a sharp version worth running once. Imagine you have just learned your time is far shorter than you assumed. Notice what instantly goes trivial, the grudge, the status worry, the meeting that felt urgent, and what instantly becomes non-negotiable. That redistribution is information: it shows you the priorities you hold underneath the ones you perform. Most people only see the ranking from a hospital corridor, when it is too late to act on it. The philosophy’s suggestion is to consult it now, while there is still road ahead.

What it does not give you

Be clear about the limits, because overselling this philosophy is a way of misusing it.

It gives you no content. Stoicism tells you what to value, virtue. Buddhism tells you the goal, the end of craving. Existentialism refuses to tell you what to choose, on principle, because supplying the answer would contradict the entire claim that you must author it yourself. This is honest but it means the philosophy can diagnose bad faith and demand authenticity without giving you a single instruction about what an authentic life should contain. Some people find this liberating and some find it useless, and both are responding to a real feature. If you want to be told what to do, this is the wrong philosophy. It hands you the freedom and the responsibility and then, deliberately, stops talking.

There is also a real failure mode. I’m just being authentic can become its own bad faith, an excuse for selfishness, cruelty, or caprice dressed up as existential courage. Authenticity is not a licence; de Beauvoir’s point is that your freedom is bound to others’, so owning your freedom includes owning its effect on theirs. Anyone using existentialism purely to justify doing what they wanted anyway has missed the responsibility half and kept only the freedom half, which is exactly the imbalance the philosophy warns against.

The one thing to keep

If you discard everything else: your life is yours, you are authoring it right now whether you admit it or not, and the I have to you tell yourself is nearly always an I am choosing to in disguise. You can spend your existence executing a script you never read and calling it fate, or you can take the harder position of owning the choices, including the constraints you cannot change but can still decide how to meet. Nothing outside you will supply the meaning or grant permission. The freedom is already yours. The only question existentialism asks is whether you will use it on purpose or keep pretending you do not have it.

Terms

Go Deeper

This book compressed a sprawling, contested tradition into an hour. If you want the real thing, the tradition largely lives in novels and dense treatises. Start where it is most alive.

The best way in.

Sarah Bakewell, At the Existentialist Café. A narrative history that threads the ideas, freedom, bad faith, authenticity, through the actual lives, friendships, and feuds of the people who argued them out in wartime Paris. Named one of the New York Times ten best books of its year, and the most praised popular introduction of the past decade. If you have bounced off the primary texts, start here; the ideas land once you have met the people.

The short primary text.

Jean-Paul Sartre, Existentialism is a Humanism. Under a hundred pages, distilling existence precedes essence into its clearest form. One caveat, which Sartre himself conceded: it oversimplifies his own philosophy. Read it as a doorway, not the full room.

Through fiction.

Albert Camus, The Stranger, the most accessible gateway to the absurd, philosophy delivered as story. Pair it with his essay The Myth of Sisyphus for the argument in full. Sartre’s novel Nausea does the same job for anxiety and contingency.

The ethics.

Simone de Beauvoir, The Ethics of Ambiguity, the clearest statement of existentialist ethics and the repair to the charge that the philosophy has none. Then The Second Sex, its single most consequential application.

If you want the hard core.

Sartre’s Being and Nothingness and Heidegger’s Being and Time are the primary treatises. Both are difficult and neither is a starting point. Approach them last, if at all.

Notes and Sources

Existentialism is a literary and philosophical movement rather than a doctrine with a fixed canon, so these notes point to the key works behind each idea and flag the historical and biographical claims, several of which are contested. Publication dates are given for the primary works.

The Core Ideas

Existence precedes essence. Sartre’s formula, given its clearest statement in his 1945 lecture Existentialism is a Humanism and developed at length in Being and Nothingness (1943). The paper-knife illustration is Sartre’s own.

The death of God. Nietzsche’s phrase, from The Gay Science (1882) and Thus Spoke Zarathustra (1883-85). The reading given here, a cultural diagnosis of lost foundations rather than triumphant atheism, is the mainstream scholarly one.

Condemned to be free. Sartre, Being and Nothingness (1943) and the 1945 lecture. The objection from neuroscience and behavioural genetics is the author’s framing of a standard modern criticism; the move to a situated freedom is de Beauvoir’s position and Sartre’s later one, not a recent invention.

Anxiety. Kierkegaard, The Concept of Anxiety (1844), the source of the dizziness of freedom. Heidegger’s distinct account of anxiety, as different in kind from fear, is in Being and Time (1927) and is deliberately simplified here.

Bad faith. Sartre, Being and Nothingness (1943), including the example of the cafe waiter.

Abandonment and the young man. Sartre’s account of abandonment, and the example of the student torn between the Free French and his mother, are from the 1945 lecture Existentialism is a Humanism, alongside the companion terms anguish and despair.

The absurd. Camus, The Myth of Sisyphus (1942), which opens with the claim about suicide and closes with Sisyphus. Camus’s rejection of the existentialist label, and his objection to Kierkegaard’s leap of faith as philosophical suicide, are stated in the same work. The three consequences he draws from the absurd, revolt, freedom, and passion, are from the same book.

Death and authenticity. Being-toward-death and das Man are from Heidegger, Being and Time (1927), simplified here as flagged. Kierkegaard’s becoming a self runs through The Sickness unto Death (1849).

Freedom and other people. Sartre’s analysis of the look is in Being and Nothingness (1943); the line hell is other people is from his play No Exit (1944). De Beauvoir’s ethics is in The Ethics of Ambiguity (1947); one is not born, but rather becomes, a woman is from The Second Sex (1949).

How It Actually Works

The historical crisis. The account of existentialism as a response to the collapse of a divine or rational guarantor of meaning is the standard framing, as is the split between religious existentialism (Kierkegaard, Jaspers, Marcel) and atheistic existentialism (Sartre, Camus).

The line of development. Kierkegaard (1813-1855), writing in the 1840s against Hegel; Nietzsche (1844-1900), writing in the 1880s; Husserl’s phenomenology; Heidegger’s Being and Time (1927); Sartre’s Being and Nothingness (1943) and his 1945 lecture, which made existentialism a public movement and which Sartre himself later judged too crude.

What the precursors built. Kierkegaard’s three stages of existence, aesthetic, ethical, and religious, are set out across Either/Or (1843), which treats the aesthetic and ethical, and Stages on Life’s Way (1845), which treats the religious; Abraham as the knight of faith is from Fear and Trembling (1843). Nietzsche’s eternal recurrence is posed as a thought experiment in The Gay Science, section 341 (1882), and is central to Thus Spoke Zarathustra; the Ubermensch and the will to power belong to the same late period. The reading of the recurrence as a test of life-affirmation is the mainstream one.

Phenomenology and being-in-the-world. The phenomenological method derives from Edmund Husserl; being-in-the-world, and the critique of the detached Cartesian subject, are Heidegger’s, in Being and Time.

Thrownness and facticity. Thrownness (Geworfenheit) is Heidegger’s term; facticity is Sartre’s; situation is de Beauvoir’s refinement, developed in The Ethics of Ambiguity and The Second Sex.

What People Get Wrong

Camus and the label. Camus rejected the existentialist label repeatedly. He and Sartre split publicly in 1952, after Camus’s The Rebel (1951) received a hostile review in Sartre’s journal Les Temps Modernes; the ensuing exchange of open letters ended their friendship. Verified against multiple sources.

Nietzsche and Nazism. The association of Nietzsche with Nazism is largely the work of his sister Elisabeth Forster-Nietzsche, an antisemite and later Nazi sympathiser who controlled and edited his literary estate after his 1889 collapse, including assembling the posthumous compilation The Will to Power. Nietzsche himself repudiated antisemitism and German nationalism. This is the mainstream scholarly view.

Heidegger and Nazism. Documented fact, not smear: Heidegger was elected rector of Freiburg in April 1933, joined the Nazi Party on 1 May 1933, resigned the rectorship in April 1934, and remained a party member until 1945; his later notebooks contain antisemitic passages. Whether and how far his philosophy is implicated is disputed among scholars, with no consensus. Verified against the Stanford Encyclopedia of Philosophy and standard sources.

The ethics objection. The charge that existentialism lacks a social or ethical dimension is answered by de Beauvoir’s The Ethics of Ambiguity (1947) and The Second Sex (1949), and by Sartre’s later turn toward Marxism. The movement’s later decline, displaced in French thought by structuralism and post-structuralism, and the absorption of its themes into existential psychotherapy (Rollo May, Viktor Frankl, Irvin Yalom) and second-wave feminism, follows the standard historical account.

Bibliography

Primary works

Kierkegaard, Soren. The Concept of Anxiety (1844) and The Sickness unto Death (1849).

Nietzsche, Friedrich. The Gay Science (1882) and Thus Spoke Zarathustra (1883-85).

Heidegger, Martin. Being and Time (1927).

Sartre, Jean-Paul. Nausea (1938), Being and Nothingness (1943), No Exit (1944), and Existentialism is a Humanism (1945).

Camus, Albert. The Stranger (1942), The Myth of Sisyphus (1942), and The Rebel (1951).

de Beauvoir, Simone. The Ethics of Ambiguity (1947) and The Second Sex (1949).

Modern works

Bakewell, Sarah. At the Existentialist Café: Freedom, Being, and Apricot Cocktails. London: Chatto and Windus, 2016.

Flynn, Thomas. Existentialism: A Very Short Introduction. Oxford: Oxford University Press, 2006.

Crowell, Steven, ed. The Cambridge Companion to Existentialism. Cambridge: Cambridge University Press, 2012.

Kaufmann, Walter. Existentialism from Dostoevsky to Sartre. New York: Meridian, 1956.