Why do we act the way we do?

Have you ever noticed that when someone wants something, they will do almost anything to try to get it. I ran into this tonight. Someone knew that another person did not like what they were going to watch, but they wanted to watch a certain special, so they orchestrated it so that the other person would be forced into dealing with it, regardless of the other person's feelings. The other person was put into a very miserable situation.

It is amazing how selfish we can get. We stop caring about other people's feelings because all we want to do is stroke our own. A sad state of affairs our selfish hearts fall into. I hope that I do not treat other people's feelings so casually. I know that I can be selfish, I just hope that there is a limit to my selfishness and that it stops at hurt or ticking off other people.