and naïvely throughout the history of ontology: specifically, time has functioned as the criterion for discriminating various realms of beings (e.g., temporal/eternal)—thus for determining modes of Being. This means, then, that Being itself—and not only beings “in time”—has a temporal character. To mark this distinction terminologically, Heidegger introduces the word Temporalität, in distinction from Zeitlichkeit (temporale/zeitlich).
Heidegger then sums up the task of division 3: “We shall call the originary [ürsprunglich] determination of the meaning of Being and its characters and modes on the basis [aus, from out of] of time [Zeit] its temporal [temporale] determination. The fundamental ontological task of the interpretation of Being [Sein] as such thus includes in itself the working out [Herausarbeitung] of the temporality of Being [Temporalität des Seins]. In the exposition of the problematic of temporality, the concrete answer to the question of the meaning of Being is first given” (BT 19/18).
We can thus distinguish among three forms of time/temporality.
1. The time of beings (“worldly time”). This has been the traditional concept since Aristotle.
2. Zeitlichkeit: temporality as the meaning of the Being of Dasein.
3. Temporalität: temporality as the meaning of Being as such.
However, division 3 was never published. It is uncertain how much of it was actually written (there are rumors that Heidegger destroyed it). For understanding what division 3 might have involved, the most important source is Basic Problems of Phenomenology (summer semester 1927). At the very beginning, there is a note that reads: “A new elaboration of Division III of Part I of Being and Time.” Indeed, in part 2 of Basic Problems of Phenomenology, Heidegger takes up and develops the question of die Temporalität des Seins, though he does not carry it through to completion. Basic Problems of Phenomenology is designated as a new elaboration. It is new (in contrast to what Being and Time proposed) in that it proceeds not from the outcome of Division Two but by way of an extensive discussion of four traditional theses about Being. It is then from (through the critique or destruction of) these theses that Heidegger moves to the proper task of division 3, which is to say, through a more originary appropriation of the history of Western philosophy. Here again, one sees how any simple separation between “historical” and “systematic” or analytic is precluded. In the shape that it was to have assumed in Basic Problems of Phenomenology, division 3 would have dealt with four basic problems, developing each by reference to die Temporalität des Seins:
1. The problem of the ontological difference, the difference between Being and beings. Here it would be shown how temporality makes it possible to distinguish between Being and beings.