The universe does not mete out justice. It does not believe eyes for eyes and teeth for teech.It really doesn’t give a shit about human beings. Only humans care about human beings. Only human beings can create justice or fairness in the world. And we don’t do a very good job of it. Most people’s idea of justice is to punish the bad guy. People may say that two wrongs don’t make a right, but they sure act as if they do.
To me, karma is a tipping point kind of thing. Malcolm Gladwell, the author of The Tipping Point: How Little Things Can Make a Big Difference summarizes the concept like this: “Ideas and products and messages and behaviors spread like viruses do.”
I think that behavior is catching. Courtesy is catching and discourtesy is catching. Generosity is catching, as is selfishness. Karma means that we are all viruses (examples of a behavior). The more we exhibit that behavior, the more likely it will be that people around us will “catch” it. At a certain point, enough people will have caught it that it becomes the standard for behavior and people who don’t do it get nasty looks. All the time.
It really helps if some people are a kind of doctor, running around trying to infect people with courtesy. Here at fluther, our moderators are those doctors. Of course, courtesy can be catching even when doctors don’t try to spread it.
Karma doesn’t mean you get back exactly what you put into the world. There is no one to one relationships as you describe. That’s just coincidence. Karma, I think, is not about punishment, either. Karma is that you put something good in the world, and you start the ball rolling. Or you are giving a push to a ball that is already rolling. Eventually it spreads so that wherever you go, people treat you as you have treated others in a place long ago and far away.