273 II.II
Being and Time

the there. But thrownness does not lie behind it as an event which actually occurred; something that happened to it and was again separated from Dasein. Rather, as long as it is, Dasein is constantly its "that'' as care. As this being, delivered over to which it can exist uniquely as the being which it is, it is, existing, the ground of its potentiality-of-being. Even though it has not laid the ground itself, it rests in the weight of it, which mood reveals to it as a burden.

And how is Dasein this thrown ground? Only by projecting itself upon the possibilities into which it is thrown. The self, which as such has to lay the ground of itself, can never gain power over that, ground, and yet it has to take over being the ground in existing. To be its own thrown ground is the potentiality-of-being about which care is concerned.

Being the ground [Grund-seiend], that is, existing as thrown, Dasein constantly lags behind its possibilities. It is never existent before its ground, but only from it and as it. Thus being the ground means never to gain power over one's ownmost being from the ground up. This not [Nicht] belongs to the existential meaning of thrownness. Being the ground [Grund-seiend], it itself is a nullity of itself. Nullity by no means signifies not being present or not subsisting, but means a not that constitutes this being of Dasein, its thrownness. The quality of this not as a not is determined existentially. Being [seiend] a self, Dasein, as self, is the thrown being. Not through itself, but released to itself from the [285] ground in order to be as the ground. Dasein is not itself the ground of its being, because the ground first arises from its own project, but as a self, it is the being [Sein] of its ground. The ground is always ground only for a being whose being has to take over being-the-ground.

Dasein is its ground by existing, that is, in such a. way that it understands itself in terms of possibilities and, thus understanding itself, is thrown being. But this means that, as a potentiality-of-being, it always stands in one possibility or another; it is constantly not other possibilities and has relinquished them in its existentiell project. As thrown, the project is not only determined by the nullity [Nichtigkeit] of being-the-ground, but is itself as project essentially null [nichtig]. Again, this definition by no means signifies the ontic property of being "unsuccessful" or "of no value" but an existential constituent of the structure of being of projecting. This nullity belongs to the beingfree of Dasein for its existentiell possibilities. But freedom is only in the choice of the one, that is, in bearing the fact of not having chosen and not being able also to choose the others.

In the structure of thrownness, as well as in that of the project, essentially lies a nullity. And it is the ground for the possibility of the nullity of inauthentic Dasein in its falling prey which it always already in each instance factically is. Care itself is in its essence thoroughly permeated with nullity. Care, the being of Dasein, thus means, as thrown

Martin Heidegger (GA 2) Being & Time (S&S)