to its coming-to-be under quite different ontological conditions than with regard to its decay and possible perishing. These are relationships which belong to the ontology of history and which we are merely pointing to in order to make clear the restriction under which we are saying that being within the world does not belong to the being of things extant.
World is only, if, and as long as a Dasein exists. Nature can also be when no Dasein exists. The structure of being-in-the-world makes manifest the essential peculiarity of the Dasein, that it projects a world for itself, and it does this not subsequently and occasionally but, rather, the projecting of the world belongs to the Dasein's being. In this projection the Dasein has always already stepped out beyond itself, ex-sistere, it is in a world. Consequently, it is never anything like a subjective inner sphere. The reason why we reserve the concept "existence" for the Dasein's mode of being lies in the fact that being-in-the-world belongs to this its being.
From this determination of being-in-the-world, which we cannot yet realize for ourselves in a truly phenomenological manner, we shall briefly indicate two further moments of the existential structure of the Dasein which are important for understanding what follows. The Dasein exists in the manner of being-in-the-world and as such it is for the sake of its own self. It is not the case that this being just simply is; instead, so far as it is, it is occupied with its own capacity to be. That it is for its own sake belongs to the concept of this existent being, just like the concept of being-in-the-world. The Dasein exists; that is to say, it is for the sake of its own capacity-to-be-in-the-world. Here there comes to view the structural moment that motivated Kant to define the person ontologically as an end, without inquiring into the specific structure of purposiveness and the question of its ontological possibility.
And furthermore, this being that we ourselves are and that exists for the sake of its own self is, as this being, in each case mine. The Dasein is not only, like every being in general, identical with itself in a formal-ontological sense-every thing is identical with itself-and it is also not merely, in distinction from a natural thing, conscious of this selfsameness. Instead, the Dasein has a peculiar selfsameness with itself in the sense of selfhood. It is in such a way that it is in a certain way its own, it has itself, and only on that account can it lose itself. Because selfhood belongs to existence, as in some manner 'being-one's-own," the existent Dasein can choose itself on purpose and determine its existence primarily and chiefly starting from that choice; that is, it can exist authentically. However, it can also let itself be determined in its being by others and thus exist inauthentically by existing primarily in forgetfulness of its own self. With equal originality, the Dasein