A great deal of chaos in the world occurs because people don't appreciate themselves. Having never developed sympathy or gentleness towards themselves, they cannot experience harmony or peace within themselves, and therefore what they project on to others is also inharmonious and confused. Nature is not a temple, but a workshop, and man's the workman in it. Youth means the temperamental predominance of courage over timidity, of the appetite for adventure over the love of ease. This often exists in a man of sixty more than a boy of twenty.
Nobody grows old merely by a number of years.
We grow old by deserting our ideals. Years may wrinkle the skin, but to give up enthusiasm wrinkles the soul. Whether sixty or sixteen, there is in every human being's heart the lure of wonder, the unfailing childlike appetite of what's next, and the joy of the game of living. The point of living, and of being an optimist is to be foolish enough to believe the best is yet to come. If you can't stand the heat, get out of the kitchen.