Alfred Adler
"If you don't know where you're going, you'll end up somewhere else. "
"It is easier to fight for one's principles than to live up to them. "
"The feeling of inferiority rules the mental life and can be clearly recognized as the sense of incompleteness and unfulfillment ... both of individuals and of humanity. "
"The truth is often a terrible weapon of aggression. It is possible to lie, and even murder with the truth. "
"There is a courage of happiness as well as a courage of sorrow. "