What are we? Are we, for example, souls, organisms, brains, or something else? In this book, Andrew Brenner argues that there are principled obstacles to our discovering the answer to this fundamental metaphysical question. The main competing accounts of personal ontology hold that we are either souls (or composites of soul and body), or we are composite physical objects of some sort, but, as Brenner shows, arguments for either of these options can be parodied and transformed into their opposites. Brenner also examines arguments for and against the existence of the self, offers a detailed discussion of the metaphysics of several afterlife scenarios - resurrection, reincarnation, and mind uploading -- and considers whether agnosticism with respect to personal ontology should lead us to agnosticism with respect to the possibility of life after death.