Another objection to psychological-continuity views is that they rule out our being biological organisms (Carter 1989, Ayers 1990: 278–292, Snowdon 1990, Olson 1997: 80f., 100–109, 2003a). This is because no sort of psychological continuity appears to be either necessary or sufficient for a human organism to persist. Human organisms have brute-physical persistence conditions. If your brain were transplanted, the one who ended up with that organ would be uniquely psychologically continuous with y