To be a human being means to possess a feeling of inferiority which constantly presses towards its own conquest. … The greater the feeling of inferiority that has been experienced, the more powerful is the urge for conquest and the more violent the emotional agitation.

Alfred Adler (1870-1937) Austrian psychologist

The Individual Psychology of Alfred Adler, ch. 3, sec 3 (1956) [ed. Ansbacher]