Consider someone who believes in any kind of reincarnation or perfect punishment after death, a theist. That is, all she/he does in this life is done in light of complying with her/his God(s) wishes.
Is it possible for a person like this to be genuinely selfless in the sense of leaving a better world for future generations for their own sake? If so, how?
I don't see what could prevent this hypothetical person from being selfish all his/her life, knowing that the burden will exist only for future generations and not for himself/herself.
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NOTE: this is a provocative post, meant to point that this community moderator deemed this post NOT offensive "Why should an atheist care about what happens to the world after his/her death?" but finds offensive to make counterpoints to it.