John W. Gardner, founding chairman of Common Cause, said it's a rare and high privilege to help people understand the difference they can make not only in their own lives, but also in the lives of others, simply by giving of themselves.

Gardner tells of a cheerful old man who asked the same question of just about every new acquaintance he fell into conversation with: "What have you done that you believe in and you are proud of?"

He never asked conventional questions such as "What do you do for a living?" It was always, "What have you done th…