Authenticity is the mode of being by which Da-sein reveals itself, but inauthenticity is the mode of being by which Da-sein conceals itself. Authenticity ( Eigentlichkeit) and inauthenticity ( Uneigentlichkeit) are modes of possibility for Da-sein. The factuality of Da-sein includes projected possibility, and thus it is different from the factuality of whatever is objectively present.ĭa-sein may be authentic or inauthentic, depending on whether or not its projected possibility belongs to itself. The being of Da-sein is different from the being of objective presence, because Da-sein may project its own possibility.

Thus, the ontic and ontological structure of Da-sein may be the foundation for every other kind of being. It is a kind of being that may understand not only its own being, but also other kinds of being. Da-sein is conscious being, and it is the kind of being that belongs to human beings.Īccording to Heidegger, Da-sein has both an ontic (existential) and ontological priority over other kinds of being. He uses the term 'Da-sein' to describe a mode of being that understands its own being.

Heidegger develops a phenomenological ontology that is based on the hermeneutics of Da-sein (being-there). His major works included Sein und Zeit ( Being and Time, 1927), Was ist Metaphysik? ( What is Metaphysics?, 1929), Identität und Differenz ( Identity and Difference, 1957), and Was heisst Denken? ( What is called Thinking?, 1968).īeing and Time (1927) investigates the meaning of being as defined by temporality, and it analyzes time as a horizon for the understanding of being. Martin Heidegger (1889-1976) was a German philosopher whose writings on phenomenological ontology had an important influence on the development of existentialism, philosophical hermeneutics, and twentieth century Protestant theology.

Heideggers being and time