V. The Grounding [377-378]

terms of a presencing (a determinate mode of temporality). But this says nothing at all about what space itself is. The fact that the represen ~ tation of space occurs in a temporal way does not mean that space should be reduced to "time." Instead, space and time are not only different in the number of "dimensions" they are ordinarily thought to possess but are also radically different different in their most proper essence, and only in virtue of this extreme difference do they point back to their origin, time-space. The more purely the proper essence of each is preserved and the deeper their origin is placed, so much more readily is their essence grasped as time-space in its belonging to the essence of truth as clearing ground for concealment.

1. As little as the ordinary notion of a "space of time" ["Zeitraum"J touches on what is meant by time-space [Zeit-Raum] or could even be a point of departure for a path to the essence of time-space

2. just so little is time-space merely a coupling of space and time in the sense that time, taken as the "t" of calculative formulas, would be made into the fourth parameter, whereby the four-dimensional "space" of physics is postulated. Here space and time are merely tied together, after they both have already been leveled down to the sameness of what is calculable and what makes calculation possible

3. Yet time-space is a mere coupling also in another, possibly conceivable sense: e.g., in the sense that every historical occurrence would have its "when" and "where" and thus would be determined temporally-spatially

Instead, their unity is that of the origin, and this origin can be traced only if

1. the essence of each is clarified as properly its own, and

2. each essence in itself is exhibited in its extreme separateness to the other, and

3. each essence in itself is grasped as arising from something originary; and

4. this that is originary, the common root of both, is grasped as other than they and yet such that, as a root, it needs both of them as "shoots" in order to be a root-grounding ground (= the essence of truth).

The interpretation of space and time on the basis of time-space does not seek to prove that the previous notions of space and time are "false." On the contrary, these notions will then for the first time be fitted into the (to be sure, limited) domain of their correctness, and it will be made clear that space and time are as inexhaustible in their essence as is beyng itself.