On a plenitudinous ontology, in every filled region of spacetime, there is at least one object that’s ‘exactly then and there’; one per each modal profile that the matter in the region satisfies. One of the strongest arguments for plenitude, the “argument from anthropocentrism”, puts pressure on us to accept that members of different communities correctly self-identify under different subject concepts. I explore this consequence and offer an account of selves on which self-determination is both socially and individually variant; we (...) determine our spatiotemporal boundaries, our de re modal properties, and the kind of being that we are. We do this by determining which of many candidate beings has the property of being a self. (shrink)