Doing easily what others find is difficult is talent; doing what is impossible for talent is genius.
Analysis kills spontaneity. The grain once ground into flour springs and germinates no more.
A belief is not true because it is useful.
For purposes of action nothing is more useful than narrowness of thought combined with energy of will.
"To know how to grow old is the master-work of wisdom, and one of the most difficult chapters in the great art of living."