Being and Time

Summary

Being and Time, published in 1927 by Martin Heidegger, is a systematic investigation into the nature of human existence. Heidegger argues that Western philosophy, and the scientific tradition it founded, had taken the wrong starting point by treating knowledge as the primary relation between mind and world. He proposes instead that human beings are first and foremost practical inhabitants of a meaningful world, not detached observers of neutral objects. The book introduced key concepts — Dasein, being-in-the-world, readiness-to-hand, being-toward-death, and care — that gave philosophers working in medicine and psychiatry a vocabulary for what was missing from purely biomedical accounts of illness. Its influence on clinical phenomenology, philosophy of medicine, and medical ethics has been sustained across the second half of the twentieth century and into the twenty-first.

Background and Context

Martin Heidegger published nothing between his 1916 habilitation dissertation and Being and Time in 1927.(Polt, 1999) The book appeared under pressure: the University of Marburg had recommended him for a tenured professorship, authorities in Berlin rejected the proposal on the grounds of his slim publication record, and Heidegger completed the core of what would become the finished text in a burst of work in early 1926. It appeared in April 1927 in Edmund Husserl’s Yearbook for Philosophy and Phenomenological Research.

The intellectual lineage of the book runs through two main sources. In the years before Being and Time, Heidegger’s early Freiburg lectures had treated logic and categories as timeless theoretical structures; the book represents a wholesale rejection of that standpoint, concluding instead that any purportedly presuppositionless “theory of theory” is itself rooted in living, historical engagement with the world.(Polt, 1999) Heidegger’s method for the book is phenomenological in a specific sense: it proceeds by articulating how Dasein and the world already show themselves, rather than by demonstrating truths or offering causal explanations — an approach that Polt characterizes as fundamentally descriptive.(Polt, 1999)

From Husserl, Heidegger took the goal of describing phenomena as they actually show themselves to consciousness rather than as they are theorized by natural science. Husserl had argued that intentionality — the directedness of consciousness toward objects — was the fundamental structure of experience, and had developed the phenomenological reduction as a method for bracketing scientific assumptions to return to lived experience. But Husserl’s project remained committed to a transcendental standpoint: consciousness surveying the world from a position of potential perfect clarity.(Polt, 1999) Heidegger accepted the goal of unconcealment — letting things show themselves as they are — while rejecting the possibility of any presuppositionless standpoint. The truth of experience, he argued, is necessarily accompanied by untruth, because we are historical creatures immersed in tradition, never able to step entirely outside it.(Polt, 1999)

From Wilhelm Dilthey, Heidegger inherited a different critical edge. Dilthey had argued across works like Introduction to the Human Sciences (1883) that the objects studied by history, psychology, and the humanities are essentially historical — that is, essentially us — and therefore could not be approached with the ahistorical methods appropriate to physics or chemistry.(Polt, 1999) Heidegger synthesized both streams, combining Husserl’s systematic rigor with Dilthey’s insistence on concrete, situated existence, to produce what he called a hermeneutics of facticity — a phenomenology that begins not with transcendental consciousness but with the historically embedded, practically engaged human being.(Polt, 1999)

The book was composed across three drafts, according to the scholar Theodore Kisiel: the first focused on historical existence under Dilthey’s influence, the second gave it a Husserlian emphasis on Being in general, and the third brought in Kantian themes of time and temporality.(Polt, 1999) The text that was published comprises only Part One, Divisions I and II. Division III — the step from the analysis of human existence (Dasein) to the meaning of Being in general — was never finished. Heidegger later claimed to have burned the manuscript after finding his account entirely inadequate.(Polt, 1999)

Core Arguments

The Question of Being

Being and Time opens with a citation from Plato’s Sophist on the perplexity of the word “being.” Heidegger’s opening move is to observe that while we use the word constantly, we cannot articulate what it means; what is most familiar proves most resistant to examination.(Polt, 1999) His goal is to ask the question of Being again, from the ground up. He begins with the entity that already has an understanding of Being — namely, us.

Dasein

Heidegger’s technical term for what we are is Dasein — literally “being-there.” The choice of this word is deliberate. Unlike nouns such as “subject,” “consciousness,” or “person,” Dasein resists the suggestion that human existence is a thing with fixed properties. The word “there” (Da) points to the distinctive feature of human existence: we inhabit a world, and that world makes a difference to us, whereas a rock exists somewhere without being oriented toward or caring about its situation.(Polt, 1999)

A corollary follows immediately. Dasein is not a “what” with categories but a “who” with existentialia — structural features of existence that cannot be understood by the same ontological grammar used to describe objects.(Polt, 1999) To say that Dasein has properties the way a desk has properties is to misunderstand what kind of being we are. Heidegger’s formula is blunt: “The ‘essence’ of Dasein lies in its existence.”

Being-in-the-World

The most important single concept in Division I is being-in-the-world, which Heidegger writes with hyphens to mark that it is a unitary structure, not three separate things joined together. Dasein is not a subject enclosed in a sphere who subsequently reaches out to contact external objects. We are always already at home amid a web of meaningful concerns, practical skills, and social relations. Knowledge of objects, when it occurs, is a derivative and founded mode of our more basic practical engagement with the world, not its foundation.(Polt, 1999)

Since ancient Greece, the ideal of knowledge has been what Heidegger calls the metaphysics of presence: context-free intuition, a disengaged gaze fixed on objects lying stably before it. Being and Time fights against this inheritance at every level, showing that such present-at-hand inspection of objects is only a limited, derivative mode of the more primordial understanding through which Dasein inhabits a world of practices, relationships, and purposes.(Polt, 1999)

This claim is worked out most concretely through the analysis of equipment. Things in our everyday environment are first encountered as ready-to-hand (zuhanden) — as tools defined by their place in a network of purposes. When you use a hammer, the hammer itself recedes; you are directed through it toward the nail, the shelf, the book. The hammer’s “hammerness” shows up not when you inspect it theoretically but when you use it.(Polt, 1999) It is only when a tool breaks down, goes missing, or gets in the way that it becomes obtrusive and presents itself as an object for theoretical attention — a mode Heidegger calls present-at-hand (vorhanden).(Polt, 1999) In Richard Polt’s commentary, the neurologist Oliver Sacks’s patient Dr. P., who could describe a glove as a “continuous surface with five outpouchings” but could not recognize it as a glove until he accidentally put it on, illustrates precisely what happens when ready-to-hand access is severed and only present-at-hand, theoretical inspection remains.(Polt, 1999)

The parallel to the body in illness is not incidental. When the body functions smoothly, it withdraws from awareness; we are directed through it toward the world. When it breaks down, it becomes an obtrusive object — a source of unwanted thematic attention.(James Aho, Kevin Aho, 2009) Gadamer captured the positive side of this withdrawal precisely: health shows itself above all in the feeling of well-being that enables openness to new things and forgetfulness of oneself, a transparent readiness that only becomes visible when it is gone.(James Aho, Kevin Aho, 2009) Heidegger’s tool analysis provides a structural account of this shift.

Space and Time

Heidegger replaces quantitative Cartesian space — a grid of coordinate points — with what Polt calls “the space of appropriateness”: places where meaningful things belong or do not belong, where I feel at home or out of place.(Polt, 1999) Near and far are first of all experiential categories tied to practical concern, not objective measures of distance. This lived spatiality has direct implications for illness, which characteristically shrinks the patient’s spatial world from an expansive field of possibilities (“I can”) to a horizon of obstacles (“I can’t”).(James Aho, Kevin Aho, 2009) The parallel shrinkage of lived time is equally characteristic: when the body is maimed or ill, the open temporal vista of future hopes and projects collapses into a single present-focused dimension, stripping the ecstatic temporal structure that Heidegger treats as constitutive of authentic human existence.(James Aho, Kevin Aho, 2009)

Concerning time, Heidegger argues that the ordinary understanding of time as an infinite sequence of “nows” is a derived, inauthentic abstraction from the richer temporal structure of human existence.(Polt, 1999) Primordial temporality is ecstatic: Dasein always already finds itself in a past it did not choose (thrownness), projects forward into possibilities (understanding), and makes present in its current engagements. The three dimensions of time are not points on a line but structural moments of care — modes of what Heidegger calls “standing out” of oneself.

Care

Thrownness is disclosed not through intellectual reflection but through attunement (Befindlichkeit) — the moods in which Dasein finds itself already situated. Moods are not merely subjective feelings; they reveal the world in ways that theoretical propositions cannot reach, making the character of our “facticity” manifest in a pre-cognitive way.(Polt, 1999) Alongside attunement stands understanding (Verstehen), which Heidegger treats not as the grasping of propositions but as the practical ability to deal with the world — a kind of know-how that is more fundamental than any knowing-that.(Polt, 1999) All interpretation, furthermore, is governed by a hermeneutical circle: any attempt to read a text, a situation, or an experience already presupposes fore-having (a prior acquaintance with the whole), fore-sight (a guiding point of view), and fore-conception (an anticipatory grasp of possible meanings). This is not a vicious circle but the basic structure of understanding; the task is to work it out from the things themselves rather than from fancies and conventional prejudices.(Polt, 1999)

Division I concludes by identifying care (Sorge) as the unitary structure of Dasein’s Being. Anxiety — not fear of any particular thing, but the free-floating unease in which the familiar world goes uncanny and beings “slip away” — discloses this structure.(Polt, 1999) In anxiety I discover that I am always already in a situation I did not choose (thrownness), always projecting forward into possibilities (projection), and always tending to be absorbed in current activities and conventional interpretations (falling). These three aspects — thrownness, projection, falling — are the moments of care, defined in one of the book’s most compressed formulas: “ahead-of-itself-Being-already-in-(the-world) as Being-at-home-amid (entities encountered within-the-world).”(Polt, 1999)

Care is “an implicit criticism,” as Polt notes, “of all philosophies of detachment.” There is no way to avoid being rooted in a past and faced with a future. The Stoic sage who masters his passions and achieves apatheia, the Cartesian subject who suspends all judgment and achieves methodological certainty — both are possible human projects, but both are modifications of the more primordial condition they try to escape.

Being-toward-Death

Division II opens with an argument that Division I’s account of Dasein was incomplete because it analyzed Dasein at any given moment but not across the whole of a life. Heidegger proposes that Dasein’s wholeness is constituted by its orientation toward death — not “demise” (the biological event) but mortality as an ongoing existential condition. My mortality is my “ownmost” possibility because no one can face it on my behalf.(Polt, 1999)

Authentic existence involves facing up to mortality — not morbidly, but soberly. By accepting that one’s possibilities are finite, one is liberated from triviality and enabled to choose genuinely rather than drifting with the anonymous “they-self” (das Man) — the pervasive mode in which Dasein normally exists as “one does” and “one says,” following public norms without self-determination.(Polt, 1999) The “they” is not a sociological entity; it is an ontological constant, Dasein’s tendency to level down possibilities to what anyone would think or do.(Polt, 1999)

Authenticity and Temporality

Authentic existence does not mean abandoning one’s community or tradition. Heidegger is clear that authenticity is an “existentiell modification of the ‘they,’ ” never an escape from shared life.(Polt, 1999) This has implications for how one relates to others: authentic care for another does not consist in managing their affairs or taking over their burdens (“leaping in”), but in leaping ahead — directed not toward the tasks with which the other is occupied but toward the other’s own capacity to exist, restoring rather than removing their responsibility.(Polt, 1999) It means owning up to one’s thrownness — the unchosen past that forms the ground for any choice — and projecting forward into possibilities drawn from that heritage, with the resolution that comes from accepting mortality.

The meaning of this authentic orientation is temporality (Zeitlichkeit): future, past, and present as “ecstases” in which Dasein stands out of itself toward its own coming-toward-itself, its having-been, and its making-present.(Polt, 1999) In inauthenticity, the present dominates and the past and future are subordinated to it. In authentic temporality, the priority is reversed: the future — especially the anticipation of mortality — gives fresh significance to both present and past, enabling what Heidegger calls “repetition” or retrieval: free and creative appropriation of inherited possibilities rather than passive repetition of their particular content.(Polt, 1999)

Historicity — the way Dasein “stretches along” between birth and death — follows from temporality.(Polt, 1999) Human life forms a story, a drama requiring biography rather than merely biology. This is one of the reasons the book has proved generative for narrative medicine and for phenomenological accounts of chronic illness, which disrupt precisely this capacity for self-authorship.

Reception in Philosophy of Medicine

Being and Time did not immediately enter the medical literature, but by the mid-twentieth century its conceptual vocabulary had become available to clinicians through several channels. Ludwig Binswanger and Medard Boss brought Heideggerian concepts into existential psychiatry. In the 1960s, Heidegger himself met with Swiss psychiatrists in the Zollikon Seminars, where he argued that the lived body (Leib) is not a biological object but a “bodying forth” in the meaning-structures of the world — that phenomena such as a blush, pain, or sorrow carry meaning inaccessible to physiology alone.(Svenaeus, 2018)

The broader uptake in philosophy of medicine came later and through several distinct lines.

Drew Leder and the critique of Cartesian medicine. In the 1990 volume The Body in Medical Thought (which Leder edited), and in his own work, Leder identified the Cartesian paradigm — the body as machine — as the source of medicine’s systematic dehumanization, and proposed the phenomenological concept of the lived body as the framework for an alternative.(Leder (ed.), 1992) (Leder (ed.), 1992) The tools Leder deploys are heavily Heideggerian: the body in health as “absent” (corresponding to ready-to-hand equipment), the body in illness as conspicuous and intrusive (broken tool presenting as present-at-hand). Leder termed this shift “dys-appearance” — the body thrusting itself forward into painful attention rather than withdrawing silently into the background.(Svenaeus, 2018)

Havi Carel at the University of Bristol has built a sustained phenomenology of illness using Being and Time as a primary text. Her Phenomenology of Illness (2016) begins by distinguishing disease (physiological dysfunction apprehended from the third-person perspective) from illness (the lived, first-person experience of disease), a distinction that requires the Heideggerian apparatus of being-in-the-world to articulate.(Carel, 2016) She shows that illness as a lived transformation cannot be explained as merely physical or mental dysfunction; it requires viewing personhood as embodied, situated, and world-engaged.(Carel, 2016) Carel’s most direct engagement with Heidegger extends his analysis of “ability to be” (Seinkönnen) into “inability to be” — the mode in which serious illness closes down possibilities so pervasively that the ordinary language of “near” and “far,” “easy” and “difficult,” no longer applies in the same way.(Carel, 2016) The ill body, like Heidegger’s broken tool, becomes conspicuous and constricts freedom of action.(Carel, 2016) (Carel, 2016)

Fredrik Svenaeus at Södertörn University has extended the Heideggerian framework most explicitly into biomedical ethics. His Phenomenological Bioethics (2018) argues that phenomenology has been strangely absent from bioethics, which has been dominated by analytic principles (autonomy, beneficence, non-maleficence, justice) without a deeper account of personhood.(Svenaeus, 2018) Against this background, Svenaeus draws on Heidegger’s being-in-the-world to develop his central thesis: illness is a form of suffering experienced as an unhomelike (unheimlich) mood — the German word carrying the double meaning of something hidden and fearful and of being no longer at home in one’s world.(Svenaeus, 2018) The lived world is normally one’s home territory, but in illness that homelikeness gives way: the body, one’s engagement with others, and the narrative of one’s core values all take on an estranged character.(Svenaeus, 2018) Svenaeus defines this as “an alienating mood overcoming a person and engaging her in an embodied struggle to remain at home”: a disturbance of homelikeness at three interconnected levels — the body, engagement with others in the world, and the life-narrative of core values.(Svenaeus, 2018) Pain is not merely a sensation but a mood in the Heideggerian sense: it transforms the entire world of the sufferer, changing the meaning and appearance of everything encountered.(Svenaeus, 2018)

Svenaeus also applies Heidegger’s later concept of Gestell (enframing) — a revelation of beings as manipulable standing-reserve — to the medical-technological complex. When patients are managed as “a supply for the clinic” or “human resources,” medicine exemplifies the Heideggerian Gestell: a world-revealing framework that comprehends persons purely as objects in a scientific-economic calculus.(Svenaeus, 2018) (Svenaeus, 2018) Heidegger’s being-toward-death becomes clinically relevant in this analysis: death, understood phenomenologically, is not merely a physiological event at the end of life but a relationship to one’s own ending that shapes how one’s life-narrative makes sense, making palliative medicine’s engagement with dying persons a question requiring more than symptom management.(Svenaeus, 2018)

Kevin Aho and Charles Aho, in Body Matters: A Phenomenology of Sickness, Disease, and Illness (2009), use Heidegger throughout to criticize the biomedical model and show how the lived body — the Leib rather than the Körper — must be recovered for medicine to do what it claims to do.(James Aho, Kevin Aho, 2009) Heidegger’s concept of ecstatic Dasein — the human being as standing outside itself, living “beyond its skin” in a region of care and concern — undergirds their argument that health and illness are inherently relational phenomena, never confined to the individual organism.(James Aho, Kevin Aho, 2009) The Heideggerian analysis of depression as “forgetfulness of Being” — the loss of poignancy caused by our preoccupation with managing beings rather than attending to the difference it makes that there is something rather than nothing — contributes their most distinctive clinical claim: that depression can be a disclosure of one’s actual sociohistorical situation, not merely a deficit of neurotransmitters.(James Aho, Kevin Aho, 2009) This is reinforced by Aho and Aho’s phenomenological reframing of depression as a condition that is not located “inside” the individual at all, but is already “out there” as part of the public atmosphere — the shared, low-key tone of a social world that has lost its vitality.(James Aho, Kevin Aho, 2009) More directly, Heidegger’s being-toward-death appears in their account of chronic illness as a catalyst for authentic existence: the enforced awareness of mortality that serious illness produces can paradoxically open the patient to what matters, reorder priorities, and enable genuine care for others.(James Aho, Kevin Aho, 2009)

Hans-Georg Gadamer occupies a distinctive position in this genealogy. As Heidegger’s student, and the architect of philosophical hermeneutics in his own right, Gadamer extended Heidegger’s critique of presence-at-hand objectivity into the theory of understanding in the human sciences.(Gadamer, 1998) (Gadamer, 1998) In The Enigma of Health (1996), Gadamer brought hermeneutical thinking directly to medicine. His argument that therapeutic dialogue is not preparation for treatment but is itself part of treatment — and must be sustained throughout recovery — is a direct application of the hermeneutical principle that understanding is dialogical, requiring two horizons to meet.(Gadamer, 1996) Gadamer’s phenomenological Körper/Leib distinction, which he calls on the German language itself to illuminate, identifies the limits of any science that measures only the objective body.(Gadamer, 1996) Svenaeus frames the clinical encounter as a “merging of horizons” in Gadamer’s sense: the doctor brings a biomedical horizon, the patient brings an illness-experience horizon, and effective care requires their genuine fusion rather than unilateral imposition of the medical framework.(Svenaeus, 2018)

Wider Significance

Being and Time belongs to the generation of European texts — alongside Husserl’s Crisis of the European Sciences (1936), Merleau-Ponty’s Phenomenology of Perception (1945), and Sartre’s Being and Nothingness (1943) — that registered the bankruptcy of nineteenth-century optimism about scientific method as the key to all human problems. The book’s reception history was shaped by the disillusionment produced by the First World War’s industrial-scale carnage and by the crisis of European liberal rationalism more broadly. Its propagation into French philosophy followed partly from Alexandre Kojève’s 1933–1939 Paris seminars, where he introduced Heidegger’s ideas to a generation of French thinkers including Maurice Merleau-Ponty, Jacques Lacan, and Georges Bataille.(James Aho, Kevin Aho, 2009)

For Western medical history specifically, Being and Time matters because it provides the most philosophically rigorous articulation of the case against Cartesian dualism in medicine. Aho and Aho trace the lineage from Descartes’s identification of the body as res extensa through La Mettrie’s L’Homme Machine to the mechanistic body-ontology that underlies cardiology, neurology, and endocrinology as they were founded.(James Aho, Kevin Aho, 2009) Heidegger’s analysis shows not merely that this model is incomplete but that it is derived: the present-at-hand body of biomedicine is a theoretical abstraction from a more primordial, practical, and meaningful way of being embodied.(Polt, 1999) Heidegger’s later concept of Machination (Machenschaft) deepens this critique: not merely an individual act of manipulation, Machination names a historical revelation of beings as a whole in which everything — including human bodies, emotions, and relationships — is comprehended as exploitable, manipulable resource, with quality reduced to quantity.(Polt, 1999) The critique does not dismiss scientific medicine; it situates it as one legitimate mode of disclosure, appropriate to certain tasks, but incapable on its own of attending to what illness does to a person’s world.

Aho and Aho extend this into a broader cultural diagnosis: the scientism they inherit from Heidegger and Weber’s “iron cage” has severed the event of life from its connection to the earth and to other living beings, so that the more medicine treats the body as an object to be fixed by technical procedures, the more it generates the very anxiety of not-being-at-home (Unheimlichkeit) that illness already brings.(James Aho, Kevin Aho, 2009) This analysis carries implications for contemporary debates about enhancement and transhumanism: Aho and Aho argue that the idea of downloading consciousness into a digital substrate is phenomenologically incoherent, because human existence is not a transferable informational content but an irreducibly embodied, temporal, and situated way of being-in-the-world.(James Aho, Kevin Aho, 2009)

The book’s “formal indication” method — using concepts to point toward familiar phenomena in experience rather than to capture them theoretically(Polt, 1999) — also bears on medical education. Heidegger’s claim that human life must be understood from the inside, that “I learn what it is to be human not by measuring and scrutinizing examples of Homo sapiens, but by being human,“(Polt, 1999) anticipates the case for narrative medicine, for Stein’s phenomenology of empathy as clinical epistemology, and for what Svenaeus calls the irreducibly first-person dimension of illness experience that no third-person measurement can substitute for.(Svenaeus, 2018)

Scholarly Assessment

The secondary literature on Being and Time is vast and contested. Richard Polt’s Heidegger: An Introduction (1999) summarizes the main interpretive positions while being frank about the book’s difficulties and limitations. Polt identifies several fault lines in the text that are directly relevant to its medical reception.

One is the formal emptiness of authentic choice. Heidegger’s account of resoluteness tells us to choose, but offers no guidelines about what to choose; it is possible to be resolutely anything.(Polt, 1999) This formal emptiness has been read as a structural condition of possibility for Heidegger’s engagement with National Socialism — his appointment as rector of the University of Freiburg in 1933, his support for Hitler, his implementation of racial dismissal policies.(Polt, 1999) The Black Notebooks, published from 2014, added antisemitic passages in which “world Judaism” is characterized as an uprooting, machination-serving force.(Polt, 1999) Polt concludes that these political failures are not peripheral but lead “straight to the heart of” Heidegger’s philosophy — its communitarianism, its anti-Enlightenment stance on universal values, its identification of authenticity with resoluteness within a particular heritage.(Polt, 1999) Any use of Being and Time in medical ethics must reckon with these facts and decide whether the conceptual framework can be extracted from its author’s practice, or whether something in the structure of the concepts themselves enabled or invited the catastrophic choices.

A second limitation is the incompleteness of the book. Division III was never published, and without it the work’s announced goal — to show that time is the meaning of Being in general, not just of Dasein — remains a promissory note.(Polt, 1999) The Kehre (turn) in Heidegger’s later work, which shifted emphasis from Dasein’s understanding of Being to Being’s claim on Dasein, represents Heidegger’s own recognition that the Being and Time framework was inadequate.(Polt, 1999)

A third question concerns whether Heidegger’s existential analytic is genuinely universal or implicitly particular. The concept of being-in-the-world includes the co-structural feature of being-with (Mitsein), and even solitude is analyzed as a mode of being-with;(Polt, 1999) but critics have argued that the analysis privileges an atomized individual striving for authentic resoluteness at the expense of genuinely relational or communal modes of existence. For clinical phenomenology, where the patient’s illness always unfolds within relationships — to carers, family, clinicians, and community — this tension matters. Svenaeus, Carel, and the Ahos all supplement Heidegger with Merleau-Ponty’s more radically embodied and intercorporeal account to address this gap.

Within the medical reception, the central critical question is how far Heidegger’s analysis of Dasein’s structure — drawn from what he calls existentiell experience, necessarily his own way of existing(Polt, 1999) — can be applied to patients whose experience of illness differs profoundly from the healthy, able-bodied philosopher engaged in existential self-examination. Carel addresses this directly through her own experience of lymphangioleiomyomatosis (LAM), a rare lung disease, using it as first-person evidence that Heidegger’s structures of being-unable-to-be, loss of certainty, and shrinkage of temporal horizon are not merely theoretical elaborations but verifiable phenomenological findings — while also insisting that serious illness permanently modifies the structures in ways Heidegger did not examine.(Carel, 2016) (Carel, 2016)