Martin Heidegger (1889—1976), by W. J. Korab-Karpowicz, The Internet Encyclopedia of Philosophy (IEP) (ISSN 2161-0002),https://iep.utm.edu/heidegge/#H3, 2024/03/28

3. Dasein and Temporality

In everyday German language the word “Dasein” means life or existence. The noun is used by other German philosophers to denote the existence of any entity. However, Heidegger breaks the word down to its components “Da” and “Sein,” and gives to it a special meaning which is related to his answer to the question of who the human being is. He relates this question to the question of being. Dasein, that being which we ourselves are, is distinguished from all other beings by the fact that it makes issue of its own being. It stands out to being. As Da-sein, it is the site, “Da”, for the disclosure of being, “Sein.”

Heidegger’s fundamental analysis of Dasein from Being and Time points to temporality as the primordial meaning of Dasein’s being. Dasein is essentially temporal. Its temporal character is derived from the tripartite ontological structure: existence, thrownness, and fallenness by which Dasein’s being is described. Existence means that Dasein is potentiality-for-being (Seinkönnen); it projects its being upon various possibilities. Existence represents thus the phenomenon of the future. Then, as thrownness, Dasein always finds itself already in a certain spiritual and material, historically conditioned environment; in short, in the world, in which the space of possibilities is always somehow limited. This represents the phenomenon of the past as having-been. Finally, as fallenness, Dasein exists in the midst of beings which are both Dasein and not Dasein. The encounter with those beings, “being-alongside” or “being-with” them, is made possible for Dasein by the presence of those beings within-the-world. This represents the primordial phenomenon of the present. Accordingly, Dasein is not temporal for the mere reason that it exists “in time,” but because its very being is rooted in temporality: the original unity of the future, the past and the present. Temporality cannot be identified with ordinary clock time – with simply being at one point in time, at one “Now” after another—which for Heidegger is a derivative phenomenon. Neither does Dasein’s temporality have the merely quantitative, homogeneous character of the concept of time found in natural science. It is the phenomenon of original time, of the time which “temporalizes” itself in the course of Dasein’s existence. It is a movement through a world as a space of possibilities. The “going back” to the possibilities that have been (the past) in the moment of thrownness, and their projection in the resolute movement “coming towards” (the future) in the moment of existence, which both take place in “being with” others (the present) in the moment of fallenness, provide for the original unity of the future, the past, and the present which constitutes authentic temporality.

As authentically temporal, Dasein as potentiality-for-being comes towards itself in its possibilities of being by going back to what has been; it always comes towards itself from out of a possibility of itself. Hence, it comports itself towards the future by always coming back to its past; the past which is not merely past but still around as having-been. But in this “going back” to what it has been which is constitutive together with “coming towards” and “being with” for the unity of Dasein’s temporality, Dasein hands down to itself its own historical “heritage,” namely, the possibilities of being that have come down to it. As authentically temporal, Dasein is thus authentically historical. The repetition of the possibilities of existence, of that which has been, is for Heidegger constitutive for the phenomenon of original history which is rooted in temporality.