The belief that youth is the happiest time of life is founded upon a fallacy. The happiest person is the person who thinks the most interesting thoughts, and we grow happier as we grow older.

Unbeing dead isn't being alive.

I thought I was growing wings—but I was only growing old.

My great concern is not whether you have failed, but whether you are content with your failure.

Do one thing at a time and while doing it, put your whole soul into it to the exclusion of all else.

If you have knowledge, let others light their candles in it

Just one small positive thought in the morning can change your whole day.