There is a popular view in metaphysics: a mental state exists at a time and depends on a brain state at that time. This is difficult to reconcile with a central claim from special relativity: what exists at a time depends on an arbitrary foliation of spacetime. Together, these seem to suggest that brain states and their accompanying mental states depend on arbitrary foliations of spacetime. I argue that a further implication is that there could be rogue mental states and, worse, rogue persons that overlap with an ordinary person, but that are nonetheless introspectively inaccessible to that person. I go on to argue that functional and intelligibility requirements allow us to privilege a person's rest foliation. I conclude that most rogue mental states are unintelligible and that rogue persons are exceedingly rare.
Heather Demarest (Tue,) studied this question.