Review by Alex Scott

Martin Heidegger’s Being and Time (1927) is an exploration of the meaning of being as defined by temporality, and is an analysis of time as a horizon for the understanding of being. Heidegger presents his view of philosophy as phenomenological ontology, beginning with the hermeneutics of Da-sein (there-being). Da-sein is a term used by Heidegger to refer to being which understands its own being. Da-sein is conscious being, and is the kind of consciousness which belongs to human beings.

Heidegger argues that Da-sein has both an ontic (existential) and ontological priority over other kinds of being. Da-sein is a kind of being which can understand the existence of beings other than itself. Thus, the ontic and ontological structure of Da-sein is the foundation for every other kind of being.

The being of Da-sein is different from the being of objective presence, in that Da-sein can project its own possibility. The factuality of Da-sein, which includes projected possibility, is different from the factuality of what is objectively present.

Da-sein may be authentic or inauthentic, depending on whether its projected possibility belongs, or does not belong, to itself. Authenticity and inauthenticity are thus modes or conditions of possibility. Da-sein reveals itself by authenticity, and conceals itself by inauthenticity. Authenticity and inauthentity are fundamental existential possibilities or determinations of Da-sein.

The possible determinations of Da-sein or of other kinds of being vary in their ontological character. Heidegger refers to determinations of Da-sein as “existentials,” while he refers to determinations of being unlike Da-sein as “categories.” Existential determinations are neither “things at hand” nor “things objectively present,” but are instead constituents of the being of Da-sein. Categorial determinations, on the other hand, refer to “things at hand” or to “things objectively present.”

Heidegger distinguishes between “things at hand” and “things objectively present” as different modes of categorial determination. “Things at hand” are encountered by Da-sein in its concern with, or in its taking care of, the world. Things at hand may be useful or “handy.” Things objectively present may also become objects of concern for Da-sein. Things objectively present are important constituents of the actuality or reality of the world. While “handiness” is the being of beings initially encountered by Da-sein, “objective presence” is the being of beings found to be of concern after Da-sein has encountered what is at hand.

According to Heidegger, categorial determinations include: handiness, objective presence, conspicuousness, obtrusiveness, obstinacy, thingliness, and remoteness. Existential determinations include: temporality, spatiality, being-in-the-world, worldliness, nearness, disclosedness, thrownness, attunement, understanding, interpretation, significance, discourse, language, idle talk, curiosity, ambiguity, and falling prey.

Da-sein (there-being) is always being-in-the-world. The world includes the totality of “things at hand” and “things objectively present,” but is also the realm in which Da-sein has its being. The world is a constitutive factor of Da-sein. The world is a structural component of being-in-the-world.

Da-sein as being-in-the-world has both temporality and spatiality. The spatiality of Da-sein includes de-distancing and directionality. De-distancing is a mode of bringing beings nearer to each other. Da-sein is a mode of being that de-distances being in space. Heidegger argues that Da-sein is a nearness rather than a remoteness. The nearness which is determined by Da-sein has a character of directionality.

Da-sein is disclosed to itself by attunement, by understanding, and by discourse. Attunement is a mode by which the mood and thrown possibility of Da-sein are disclosed to itself. Understanding is a mode by which the meaning and significance of being-in-the-world are disclosed to Da-sein. Discourse is the mode by which the intelligibility of Da-sein can be communicated.

The “there” of there-being may be disclosed by attunement or by understanding. The “there” of there-being is also the thrownness of its being, in that Da-sein always discovers that it is already in-the-world. Da-sein is attuned to itself when it discovers its own mood, and when it discovers the thrownness of its being.

Da-sein is factical, in that it is thrown being-in-the-world. Da-sein understands its own thrownness by projecting itself as factical potentiality. Facticity or thrownness is the “there” of Da-sein.

Disclosedness may be authentic or inauthentic. Da-sein may be disclosed to itself authentically or inauthentically in relation to its existence and thrown potentiality.

Heidegger declares that truth is the disclosedness of Da-sein. There can be no truth without Da-sein. The full disclosedness of Da-sein is based on its concern with being-in-the-world.

Heidegger describes fear as a mode of attunement, and says that it may be caused by something which is at hand or by something which is objectively present. Fear may become alarm, horror, or terror. Fear concerning the well-being of others may be a mode of attunement to others.

Heidegger also distinguishes between fear and Angst. Fear may be caused by something definite, by something which is at hand, or by something which is objectively present. Angst may be caused by something indefinite, by something which is not at hand, or by something which is not objectively present. Fear may be an apprehension of an innerworldly being, while Angst is not an apprehension of an innerworldly being. Fear may cause flight from something at hand, or from something objectively present, while Angst may cause flight from Da-sein itself.

Da-sein may be disclosed to itself as a projection of itself toward its own potentiality. The freedom of Da-sein to understand its own potentiality may also be the freedom to project itself authentically or inauthentically. Da-sein is free to project, or not to project, itself. Da-sein is free to reveal or conceal itself.

Da-sein reveals itself as care, not only in its being-with things at hand or with things objectively present, but in its being-in-the-world. Thus, being-with things at hand or being-with things objectively present also means being concerned with, or taking care of, them.

Care includes taking care of things at hand, taking care of things objectively present, and taking care of Da-sein itself. According to Heidegger, care brings things nearer to Da-sein.Care is circumspect when it discovers things at hand. Care is heedful when it discovers not only things at hand, but things not at hand.

Da-sein takes care of things, and takes care of other beings. Da-sein takes care of being and time. Da-sein is fundamentally concerned about its mode of being, and thus becomes attuned to projecting its own potentiality.

Being-with-others, having concern for others, and taking care of the world are modes by which Da-sein becomes attuned to being-in-the-world. Thus, the being of Da-sein reveals a care and concern by which Da-sein understands and transcends itself.

Heidegger describes conscience as a call of care, which summons Da-sein to return from falling prey to the world. Falling prey to the world is a form of inauthenticity, in that Da-sein becomes absorbed by being-with-others, being-with things at hand, or being-with things objectively present, to the extent that Da-sein no longer reveals itself. Conscience enables Da-sein to recognize what is lacking in its being, and to redirect itself toward its full potentiality. The call of conscience is to take care of other beings, and of being-in-the-world.

According to Heidegger, resoluteness is the mode by which Da-sein is disclosed to itself as wanting to act according to conscience. Resoluteness is a willingness of Da-sein to project itself into situations in which it may feel guilty for not having taken care of things, and in which it thus may experience Angst. Resoluteness is a freedom from fear, and is an acceptance of Angst as an existential possibility. Resoluteness is authentic being-in-the-world, in that Da-sein takes care of things, of other beings, and of its own mode of being.

Heidegger describes anticipatory resoluteness as being ahead-of-itself. Anticipation refers to the “not yet,” while thrownness refers to the “already projected.” Authentic existence is resolute, while inauthentic existence is irresolute.

According to Heidegger, being-toward-death is attunement to no-longer-being-in-the-world. Authentic being-toward-death is attunement to death as an existential possibility. Inauthentic being-toward-death is a lack of attunement to death as an existential possibility. Being-toward-death is Angst insofar as it is an attunement to death as a negation of the individualized being of Da-sein. Angst may arise when Da-sein is faced with the possible annihilation of its existence.

Heidegger explains that Da-sein is a temporal mode of being. Authentic temporality is the being of Da-sein, while inauthentic temporality is the being of innerworldy things or beings unlike Da-sein. Time is a structural factor for Da-sein. Temporality makes possible the historicity of Da-sein, which may be undisclosed or concealed but may be discovered by historical inquiry. The historicity of Da-sein means that ontological inquiry also has its own historicity.

Da-sein understands itself by projecting itself as its thrown possibility. The thrownness of Da-sein is its “having been,” and the projected possibility of Da-sein is its “already being” and its “not yet.” Thus, Da-sein unifies the past, the present, and the future. The past, present, and future are referred to by Heidegger as the “ecstacies” of temporality. Temporality is “ecstatic,” and is the meaning of there-being. Da-sein temporalizes itself in its being-in-the-world. Da-sein reveals the “ecstatic” unity of temporality.

Heidegger concludes that the distinction between Da-sein and other kinds of being is only the beginning of ontology, and that temporality as the meaning of being still needs to be further explained. If temporality is the meaning of being, what is the meaning of temporality? Heidegger does not fully answer this question, but leaves it open to further investigation.


Martin Heidegger. Being and Time. Translated by Joan Stambaugh. Albany: State University of New York Press, 1953.

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