To laugh often and much; to win the respect of intelligent people and the affection of children...to leave the world a better place...to know even one life has breathed easier because you have lived. This is to have succeeded.
The purpose of life is not to be happy. It is to be useful, to be honorable, to be compassionate, to have it make some difference that you have lived and lived well.
Neither is a dictionary a bad book to read. There is no cant in it, no excess of explanation, and it is full of suggestions, the raw material of possible poems and histories.