I believe in Karma because I have found that in the past when I did many things I am not proud of they always came back to haunt me later on. Since then I've come to understand that perhaps there is an underlying force that does in fact keep things balanced when you do good and vice versa. For myself, it seems the only possible explanation. Alot of times things happen to us and in that instant it may seem like nothing is working out and that it could be some kind of "punishment" we had coming to us...until we look at it again in hindsight and realize that it was just what needed to happen in order for today to be so great.
I treat everyone as I'd like to be treated...most of the time