The title of this chapter is perverse.1 We know that for Niklas Luhmann, ontology is not a perennial puzzle to be solved anew, but a historically-determined category to be dismissed.2 Synonymous with the Western metaphysical tradition that is anchored by Aristotelian logic, ontology is correlated with the pattern of social organization characterized by the epoch of regional high cultures, namely the hierarchically ordered form of differentiation for which Luhmann uses the sociological and anthropological label ‘stratification.’ That the word ‘ontology’ first appears in the sixteenth century, now marking a subset of metaphysics, is taken by Luhmann as a sign of crisis, or, less dramatically, a sign of transition; and that the semantics of ontology, along with a host of other traditional concepts (such as ontology’s necessary cohort, reason), continues to play an acknowledged or unacknowledged role to this day is, for Luhmann, simply an indicator that some people have not been paying attention. What they have not been paying attention to is the emergence of a new form of social structure, functional differentiation, which, Luhmann claims, is planetary and no longer associated with regional differences. Accordingly, the stable ontology of old Europe must necessarily be replaced by a way of thinking more in tune with our complex, contemporary form of social organization.