Comment by ahartmetz
There are other people in the world.
Similar to not caring at all about the rest of society when you're alive, not caring at all about the rest of society when you're dead makes for a shitty society. You are not the world, there is an external reality (with people in it!), and you have obligations to it. I'm not a religious person, but it seems to me that religion helps or used to help with such things.