The secret to true happiness

I have a tendency to observe people. I like to learn from others by observation so I don't have to go around making all the mistakes myself. Now don't get me wrong, I make mistakes, but I like to think I've learned a few things along the way from my observations that helped me out, for example; I have been noticing, mostly as I watch television and movies lately that people are very selfish and that their selfishness creates unhappiness. So if selfish people are unhappy, then unselfish people are happy. Unselfishness is the secret to true happiness. Your welcome.