McNeill: being-possible [Möglichsein]

The ontological determination of Dasein  —that is, of the being that we ourselves in each case are—is primarily possibility. “Dasein,” Heidegger writes, “is not   something present at hand   that in addition has [or possesses] the ability to do something; rather, it is primarily being-possible [Möglichsein  ], Dasein is in each case what it can be and how it is its possibility” (SZ   143). We are not primarily something actual that has the additional feature of being able to do something, or of having possibilities. Rather, insofar as we are actual, this being actual, this actuality of ourselves as actual, is already held   or suspended, as it were, within the dimension of possibility. Moreover, we do not simply have possibilities, we are possibility: our being is primarily being-possible. Possibility in this sense, Heidegger emphasizes, is not to be understood as that which is not yet actual; it is not a modal category that is ontologically lesser than actuality or necessity:

The being-possible that Dasein in each case is existentially [i.e., ontologically, in terms of its very being] is to be distinguished just as much from empty, logical possibility as from the contingency that attends something present at hand insofar as something can “happen” to the latter. As a modal category of presence at hand, possibility signifies that which is not yet actual and that which is not always necessary. It characterizes the merely possible. Possibility as an existential, by contrast, is the most primordial [or originary] and ultimate positive   ontological determinacy of Dasein; initially, […] it can only be prepared as a problem. (143-44)

The centrality and primacy of possibility for Dasein’s being could scarcely be more emphatically stated. Several points bear emphasizing with regard to this initial sketch. First, if possibility, in the sense of being-possible, is not to be understood as that which is not yet actual, it is because it is that which already is, the dimension within which everything actual is already suspended. But this indicates only that the being of possibility, its already being, is not reducible to, and cannot be understood phenomenologically in terms of, actuality. What kind of being pertains, then, to possibility? What is strange, peculiar, even uncanny “actuality,” or perhaps better, force? In what way is Dasein as possibility? Second, in hinting that the modern, Kantian understanding of possibility as a modal category refers to the not yet actual and the not always necessary, Heidegger indicates how the traditional understanding of being as primarily the actuality of presence at hand has itself led to a reductive understanding of the possible as that which is less than either the plenitude of actual presence or of that which always is, the eternal. The task of the phenomenology of Dasein, unfolding in and through a destructuring of the history of ontology, will thus be to begin to think—or to prepare, if only as a problem—the being of possibility outside or beyond the parameters of the traditional prioritizing of presence or actuality. Third—and this is a more general point—we might do well to remind ourselves here that to exist primarily as being-possible characterizes not only the being of Dasein, but the being of the living in general. If all living is a being underway, then every living being, as living, has always already surpassed what and how it actually is, surpassed it in entering into and maintaining itself within the dimension of possibility or potentiality: its living is its being capable, its possibility of being otherwise than it already is. Where such a being is no longer able to breathe, to sense, to nourish itself, or to die: there we say the being is dead. And correlatively death is a possibility only for the living. Of course, there is much more to be said here, and we cannot simply conclude from this that being means the same thing for Dasein as it does for other living beings, or that being-possible is the same, or that death and death are the same. For it is not possibility as such, Heidegger will argue, that is the sole or critical issue here, but the relation to possibility, the opening up of possibility as possibility. (v. McNeill: Möglichsein - Possibility)