Heidegger's Being and Time

The forgotten question of Being

Heidegger opens Being and Time with a quotation from Plato's Sophist: we used to know what we meant by "being," but now we are perplexed. His diagnosis is that the perplexity has hardened into avoidance. Philosophy keeps asking about beings — atoms, minds, numbers, God — and never about what we mean when we say any of them is. The most universal concept has become the emptiest.

To revive the question, Heidegger needs an entry point. He picks the entity that already has some prior understanding of Being baked into it: the human. We are the kind of being that asks the question. He renames us Dasein — literally "there-being" or "being-there" — to strip away inherited assumptions about consciousness, soul, subject, ego. Dasein is not a thinking thing dropped into a world. Dasein is the disclosure-site where Being itself shows up.

Dasein and Being-in-the-World

Modern philosophy since Descartes started with an isolated subject and tried to build a bridge to the external world. Heidegger says the bridge was built in the wrong place: there was never a gap. Dasein is constitutively Being-in-the-World, a single hyphenated phenomenon. The hyphens are the argument.

His most famous illustration is the hammer. When you swing a hammer at a nail, you don't notice the hammer; you notice the work. The tool is zuhanden — ready-to-hand — withdrawn into a context of equipment (nails, board, project, workshop). The hammer's Being is its place in this purposive web, not a list of physical properties. Only when the hammer breaks, jams, or is missing does it leap out as vorhanden — present-at-hand — an object with mass and shape, available for theoretical inspection. Theoretical knowing, Heidegger argues, is the derivative mode. Skilled coping is more fundamental.

Being-in-the-World has three structural moments Heidegger calls Befindlichkeit (attunement or mood — we always already find ourselves disposed in some way, even boredom is a mood), Verstehen (understanding as projection of possibilities), and Rede (discourse, the articulation of intelligibility). Together they make up Dasein's openness, what Heidegger calls the there in Being-there.

The They and falling

Dasein is also Being-with — we are not solitary subjects but always already among others. The trouble is that we mostly inhabit a leveled-down public mode Heidegger names das Man, "the They." The They is not a group of identifiable people; it is the anonymous voice that decides what one wears, says, finds amusing, posts about. We read what one reads. We are shocked at what one is shocked at. In das Man, every distinct possibility of existence is averaged out so that no one in particular is responsible.

This is what Heidegger calls "fallenness" (Verfallenheit) — not a moral fall but a structural drift toward absorption in the everyday. Three modes characterize it: idle talk (Gerede) that passes around without grounding, curiosity (Neugier) that flits without dwelling, and ambiguity (Zweideutigkeit) that makes it unclear what is genuinely understood and what is only repeated. Fallenness is not avoidable. Authenticity is not escape from the They but a modified relation to it.

Anxiety and Being-toward-Death

What pulls Dasein out of the They's anesthetic? Heidegger's answer is anxiety (Angst) — distinct from fear, which always has a definite object. In anxiety, the world of meaningful equipment loses its grip. Nothing in particular is threatening; the totality of involvements goes flat. What anxiety reveals is the bare fact that one is, against the possibility of not being.

This pivots the analysis toward death. Death is not an event at the end of life but a possibility constitutive of life as we live it. Heidegger gives it five characteristics: it is Dasein's ownmost (no one can die my death for me), non-relational (it isolates me from others), certain (we know it comes), indefinite (we don't know when), and not-to-be-outstripped (no possibility lies beyond it). Authentic Being-toward-Death is not depression or stoic acceptance — it is the resolute owning of finitude that lets a life become genuinely mine.

This is where Heidegger's project shifts from description to a kind of existential ethics-without-norms. Anxiety, conscience (the silent call to take up one's ownmost possibilities), and resoluteness (Entschlossenheit) form a triad that recovers Dasein from the They — not by rejecting publicness but by inhabiting it as a finite individual rather than as a faceless one.

Heidegger vs the Cartesian tradition

	Cartesian / Modern	Heidegger (Sein und Zeit)
Starting unit	Isolated thinking subject (cogito)	Being-in-the-World (single phenomenon)
Primary mode of access	Theoretical cognition	Skilled coping with equipment
Status of objects	Present-at-hand (Vorhandenheit)	Ready-to-hand (Zuhandenheit) primary
Self	Substance with properties	Care; a stretch between thrownness and projection
Time	Sequence of nows	Ecstatic temporality (past-future-present unity)
Death	Biological event	Constitutive possibility of finite existence
Others	Other minds, problem of access	Being-with, always already

The table compresses what Heidegger argues across hundreds of pages, but the throughline is consistent: every move starts from engaged Dasein, not detached observer.

Care and the temporality of Dasein

By Division One's end, Heidegger sums up Dasein's structure as Sorge — care. Care has three formal moments: existence (Being-ahead-of-itself, projecting possibilities), facticity (already-Being-in-the-World, thrown into a situation we did not choose), and fallenness (Being-alongside the entities of the world). Division Two then argues that the unity of these three moments is temporality — not clock time but the ecstatic structure in which past, future, and present co-constitute a single happening.

The future is primary. Dasein is the entity that lives forward, throwing itself toward possibilities, with its thrown past already coloring what shows up as a possibility, and a present that is the moment of decision (Augenblick, the "moment of vision," echoing Kierkegaard). On this account, time is not something Dasein is "in"; Dasein is temporality.

The promised third division — which would have moved from Dasein's temporality to the meaning of Being itself — was never published. Heidegger said in 1962 that the project's vocabulary collapsed under its own weight; later work (the "turn" or Kehre) takes up Being from the side of language and history rather than from Dasein's existential structure.

Counterarguments and reception

Three lines of critique have shaped how Being and Time is read today.

The political question. Heidegger joined the Nazi Party on May 1, 1933, served as rector of Freiburg, and gave the infamous Rectoral Address linking the German university to the National Socialist movement. The 2014 publication of his Black Notebooks (Schwarze Hefte) revealed antisemitic passages framing "world Judaism" as a metaphysical force. Critics from Habermas to Faye argue that Sein und Zeit's rhetoric of authentic destiny, historical mission, and the people (Volk) made the political turn possible. Defenders (Sheehan, Vallega-Neu) insist the philosophical content is separable. No serious reader can avoid the question.

The analytic critique. Anglophone philosophers (Carnap most pointedly, in 1932) read Heidegger's pronouncements about "the nothing nothings" (das Nichts nichtet) as grammatical confusion masquerading as metaphysics. Hubert Dreyfus's 1991 commentary Being-in-the-World rehabilitated Heidegger for analytic readers by showing the hammer-analysis as a phenomenology of skilled coping with consequences for AI and cognitive science.

The feminist critique. Simone de Beauvoir, Luce Irigaray, and others note that Dasein is described as if neuter and universal but smuggles in a specifically male, Northern European, able-bodied perspective. Birth, dependency, and embodied difference are largely absent. Heidegger's analytic of finitude reads death as constitutive while treating natality as a mere fact.

After Sein und Zeit

Heidegger's "turn" in the 1930s shifts the framework. Instead of asking how Dasein opens onto Being, he asks how Being itself sends out epochs of revealing — the Greek physis, medieval creatio, modern Gestell (enframing) of technology. The 1953 essay The Question Concerning Technology is the most cited text from this period: technology is not neutral tool-use but a way of revealing that conscripts everything as standing-reserve.

Sartre's Being and Nothingness (1943) borrows freely from Sein und Zeit while collapsing the ontological difference back into a humanist existentialism Heidegger publicly rejected in his 1947 Letter on Humanism. Levinas turns Heideggerian phenomenology toward ethics by making the face of the other prior to ontology. Hannah Arendt — who studied with Heidegger and had a complicated personal history with him — develops a political phenomenology of natality and plurality that pushes back against the death-centered analytic.

Common confusions

• Dasein is not consciousness. It is not a stream of inner experience or a Cartesian soul. It is a way of being, characterized by openness to its own being.
• Authenticity is not better than inauthenticity in a moral sense. Heidegger insists they are equiprimordial. We can never escape das Man; authenticity is a modified mode of inhabiting it.
• Being-toward-Death is not a meditation on dying. It is about how the certainty of finitude structures every present possibility, whether or not we ever explicitly think about death.
• Heidegger is not an existentialist in Sartre's sense. He explicitly disavowed the label. His project is fundamental ontology, not a humanism of radical freedom.
• The hammer example is not the whole book. It's a five-page section that became famous because it's vivid. The full analytic spans equipment, world, others, anxiety, conscience, guilt, resoluteness, and temporality.