  This all throws important light on the phenomenon of world, since we can now see that the crucial for-the-sake-of-which structure that stands at the base of each totality of involvements is culturally and historically conditioned. The specific ways in which I behave for the sake of being an academic are what one does if one wants to be considered a good academic, at this particular time, in this particular historically embedded culture (carrying out research, tutoring students, giving lectures, and so on). As Heidegger himself puts the point: “Dasein is for the sake of the ‘they’ in an everyday manner, and the ‘they’ itself articulates the referential context of significance” (Being and Time 27: 167). Worlds (the referential context of significance, networks of involvements) are then culturally and historically conditioned, from which several things seem to follow. First, Dasein's everyday world is, in the first instance, and of its very essence, a shared world. Second, Being-with and Being-in-the-world are, if not equivalent, deeply intertwined. And third, the sense in which worlds are Dasein-dependent involves some sort of cultural relativism, although, as we shall see later, this final issue is one that needs careful interpretative handling.