the discussion must anticipate subsequent analyses which only later will become truly demonstrative.
Dasein is a being that does not simply occur among other beings. Rather it is ontically distinguished by the fact that in its being this being is concerned about its very being. Thus it is constitutive of the being of Dasein to have, in its very being, a relation of being to this being. And this in tum means that Dasein understands itself in its being [Sein] in some way and with some explicitness. It is proper to this being that it be disclosed to itself with and through its being. Understanding of being is itself a determination of being of Dasein [Seinsverständnis ist selbst eine Seinsbestimmtheit des Daseins].* The ontic distinction of Dasein lies in the fact that it is ontological.
To be ontological does not yet mean to develop an ontology. Thus if we reserve the term ontology for the explicit, theoretical question of the being of beings, the ontological character of Dasein referred to here is to be designated as pre-ontological. That does not signify simply being [seiend] ontical, but rather being [seiend] in the manner of an understanding of being.
We shall call the† very being [Sein] to which‡ Dasein can relate in one way or another, and somehow always does relate, existence [Existenz]. And because the essential definition of this being cannot be accomplished by ascribing to it a what that specifies its material content, because its essence lies rather in the fact that in each instance it has to be its being [Sein] as its own, the term Dasein, as a pure expression of being, has been chosen to designate this being [Seienden].
Dasein always understands itself in terms of its existence, in terms of its possibility to be itself or not to be itself. Dasein has either chosen these possibilities itself, stumbled upon them, or in each instance already grown up in them. Existence is decided only by each Dasein itself in the manner of seizing upon or neglecting such possibilities. We come to terms with the question of existence always only through existence itself. We call this [hierbei führende] kind of understanding of oneself existentiell understanding. The question of existence is an ontic "affair" of Dasein. For this question the theoretical transparency of the ontological structure of existence is not necessary. The question of structure aims at the analysis of what constitutes existence.§ We shall call the coherence of these structures existentiality. Its analysis does not have the character of an existentiell understanding but rather an existential one. The task of an existential analysis of Dasein is prescribed [13]
* But in this case being not only as the being of human being (existence). That becomes clear from the following. Being-in-the-world includes in itself the relation of existence to being in the whole: the understanding of being.
† that
‡ as its own
§ Thus not a philosophy of existence [Existenzphilosophie].