Is it ok to do something nice for someone else for your own self-interest?

[devonin]

Exactly. I mean...if you go around doing good things for people because you are insanely selfish and outright addicted to the feeling you get when you do a good thing, and actually don't even care at all about the person to whom you are being generous or kind or helpful, that's totally fine.

This is also the reason why I don't get down on legitimately religious people for their religious beliefs. If the reason they are being kind, loving, forgiving and compassionate is because a book told them to and they believe it, what do I want? For them to be an asshole instead?

If you are being a good person for bad or incomprehensible motives, you're still being a good person.