The poetic projection differentiates, in Heidegger's view, not first in the categories of traditional logic, but in the "twofold" of the ontological difference; secondly, in the three dimensions of time–space; and thirdly, in the ontological basic structure of the world, which Heidegger calls the "fourfold". The fourfold consists of gods, mortals, heaven and earth. These four regions form the semantic poetic poles of world as world. The fourfold are four voices in which destiny—that is, Being as the appropriating event—gathers together the total infinite relatedness. The four regions appropriate each other reciprocally. One can find the structure of the fourfold implicitly already in the cura fable from Being and Time.