This paper addresses the issue of human spatiality as existential givenness, taking as its fundamental orientation relationality, namely the natural tendency towards the other as my co-man (Mitmensch) for the purposes of instituting, together with him, the first place for such a spatiality: the being-with-one-another (Miteinandersein). If the being-with-one-another embodies the first place of this spatiality, then the ">encounter between an I and a you—that is to say, otherness declined in the second person, as Duheit—represents the culmination of such a place. On this basis the τόπος of the Miteinandersein emerges as an οἶκος and the achievement of such an "oikological' rank makes the space of the relation a real Lebensraum, a living space. Given these assumptions, a comparison will be offered between two paradigmatic modes of interpreting Duheit, the outcomes of a short season in which continental philosophy questioned itself on this issue with unusual urgency and depth. On the one hand, the Zwischenontologie ("Between-ontology") of Martin Buber, on the other, the Mitanthropologie ("With-anthropology") of Karl Löwith. The comparison here proposed will reveal that the philosophical question of otherness is essentially a matter of measure, namely that the promotion of the space of the relation established by I and you to the rank of οἶκος and Lebensraum depends on its ability to stay within the limit of an anthropic perimeter.