I LOVE this! Words For Teenagers - 1959 (As Parents, we must teach this to our children!) If only I understood this as a teenager. No matter how much my parents tried to drive this into me, I didn't truly get it.
Not just happiness. I hate when people say happiness, when they mean many other things. Happiness isn't everything; this experiment is still true for those who realize that seeking only happiness is shallow. Help others, and you gain much deeper things.