
The Purpose Of Life Is Not Happiness: It’s Usefulness

Screenwriter Leo Rosten pulled everything together for us when he said, “I cannot believe that the purpose of life is to be happy. I think the purpose of life is to be useful, to be responsible, to be compassionate. It is, above all, to matter, to count, to stand for something, to have made some difference that you lived at all.”
Gary Keller • The One Thing: The Surprisingly Simple Truth Behind Extraordinary Results: Achieve your goals with one of the world's bestselling success books
Note that seeking happiness as an end might be counterproductive. Many people report that constantly checking to see if they are happy actually decreases their happiness - a report that fits with the research on "flow." It may be better to seek some of the above goals as ends, and happiness will be a side-effect.
LessWrong • How to Be Happy - LessWrong
Do you see it now? In a word, happiness is the feeling of contribution. That is the definition of happiness.
Ichiro Kishimi, Fumitake Koga • The Courage to Be Disliked: The Japanese Phenomenon That Shows You How to Change Your Life and Achieve Real Happiness
