Jeff Malpas on the topology of the event.
The Event plays a similar role, in Heidegger’s later thinking, to that played by originary temporality in Being and Time. But whereas the structure of originary temporality was that which underlay the other structures of Dasein, including iìe structure of spatiality and perhaps also of world, and from which those structures were somehow “derived,” the Event does not underlie nor is it that from which any sort of “derivation” is possible. instead, the Event encompasses earth and world, as well as mortals and gods, even as they come to appearance in the Event. At the same time, the dynamic interrelatedness of earth and world (what Heidegger refers to in "The Origin of the Work of Art" in terms of strife) is itself constitutive of the Event as such.
The structure that appears in "The Origin of the Work of Art" and that also seems present in the Contributions might be thought to be an early version of what appears later, in essays such as "Building Dwelling Thinking," as the Fourfold (Das Geviert). There is undoubtedly a lineage here but the former structure is built around what is properly a "Twofold" rather than a Fourfold, since it is constituted around one key axis, that between earth and world. There can he no doubt, however, that the structure at issue is very different from that which is set out in Being and Time. Whereas the earlier structure is indeed one that moves through a succession of ever more fundamental layers, the later structure is one of mutually related elements that are together constitutive of the overall structure at issue — that being the "there/here" that is surely best understood as topos — in which no one element takes absolute precedence over any other.
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The rethinking of world that Heidegger undertakes in the period following Being and Time is thus directly connected with his attempt to clarify the problem of world in a way that does not take world as somehow a projection of human activity, and yet nevertheless also recognizes the essential entanglement of the world with the human—the essential entanglement of being with human being. By the late 1940s, the twofold structure that appears in "The Origin of the Work of Art" and in Contributions has given way to (lie fully developed notion of the Fourfold that is familiar from a number of Heidegger’s postwar essays, including "The Thing" and "Building Dwelling Thinking." The structure of the Fourfold is analogous to that found in Contributions and in “The Origin of the Work of Art,” but whereas the earlier structure had a central earth—workl axis, tite later structure is built around two axes, earth—sky and gods—mortals, while "world" now designates not one element within the structure, but rather the dynamic unity of the structure as a whole—a unity that is also designated in terms of the Event, and that is, as I read it, essentially topological in character.