To live for something definite

"For the secret of man's being is not only to live . . . but to live for something definite. Without a firm notion of what he is living for, man will not accept life and will rather destroy himself than remain on earth." Fyodor Dostoyevsky (Entrepreneurs of Life p14)

Man without purpose

"The man without a purpose is like a ship without a rudder - a waif, a nothing, a no-man."

Thomas Carlyle (Entrepreneurs of Life p14)