I was just thinking about what I tell my kids about manners and, now, upon asking "Why do we use good manner?" they reply, with a well-tuned robotic response "...because it makes the world a better place to live..." Which leads me to karma. I've heard for years that when you do good deeds you are creating good karma. It's like there is a "good juju" bank and you're making a deposit. But that bank doesn't belong to just one person. It belongs to all. Like paying money toward social security. You're not ensuring that YOU will get social security in your old age but others ARE benefitting from that deposit now. And so with karma. You're not guaranteeing good things will happen to you. But you are making the world a nicer place to live from which all people benefit.