It's not about what _I_ feel sensible about caring about. We're talking about a hypothetical individual who cares only about versions of himself that share a co

It's not about what _I_ feel sensible about caring about. We're talking about a hypothetical individual who cares only about versions of himself that share a common ancestor or descendant state. If such an individual were given advanced knowledge of an irreversable amnesia, then logically he would commit acts that benefit him and cost the individual inhabiting his body in a day's time. So yes, it makes perfect sense. But given the same circumstances, I'd behave differently, as I'm not a sociopath.