The division of the psychical into what is conscious and what is unconscious is the fundamental premise of psycho-analysis; and it alone makes it possible for psycho-analysis to understand the pathological processes in mental life, which are as common as they are important, and to find a place for them in the framework of science.
Sigmund FreudI do not in the least underestimate bisexuality... I expect it to provide all further enlightenment.
Sigmund FreudThe view is often defended that sciences should be built up on clear and sharply defined basal concepts. In actual fact no science, not even the most exact, begins with such definitions. The true beginning of scientific activity consists rather in describing phenomena and then in proceeding to group, classify and correlate them.
Sigmund FreudMen are not gentle, friendly creatures wishing for love, who simply defend themselves if they are attacked, but ... a powerful measure of desire for aggression had to be reckoned as part of their instinctual endowment.
Sigmund Freud