I just love this quote by George Bernard Shaw quote.  I have nothing to add.

“This is the true joy in life, the being used for a purpose recognized by yourself as a mighty one; the being a force of nature instead of a feverish little clod of ailments and grievances, complaining that the world will not devote itself to making you happy. I am of the opinion that my life belongs to the whole community, and as long as I live it is my privilege to do for it whatever I can. I want to be thoroughly used up when I die, for the harder I work, the more I live. I rejoice in life for its own sake. Life is no brief candle to me; it is a sort of splendid torch which I have got hold of for the moment, and I want to make it burn brightly as possible before handing it on to future generations.”