No one is so old as those who have outlived enthusiasm. You can fool too many of the people too much of the time. It's better to know some of the questions than all of the answers. The trouble with the rat race is that even if you win you're still a rat. You can't depend on your eyes if your imagination is out of focus.
Age is an issue of mind over matter.
If you don't mind, it doesn't matter. There is no sadder sight than a young pessimist. A poem is never finished, only abandoned. Some people are so afraid to die that they never begin to live. Greatness is the dream of youth realized in old age.