Freud found considerable evidence for his theory in everyday life. He felt that forgetting, losing things, accidents, and slips of the tongue were often unconsciously motivated. He also thought jokes provide information about repressed experience be- cause people tend to find only anxiety-provoking material humorous. Freud believed that although we share the instinctual makeup of other animals, humans have the capacity to understand and harness instinctual impulses by exercising rational thought. To come to grips with the unconscious mind through rationality, however, is an extremely difficult process, and for that reason, Freud was not optimistic that rationalism would prevail over our
animal nature. Freud was especially critical of religion, believing that it is an illusion that keeps people functioning on an infantile level. His hope was that people would embrace the principles of science, thereby becoming more objective about themselves and the world.