Freud, the founder of psychoanalysis, explained the human mind as like an iceberg, with only a small amount of it being visible, that is our observable behavior, but it is the unconscious, submerged mind that has the most, underlying influence on our behavior. Freud used three main methods of accessing the unconscious mind: free association, dream analysis and slips of the tongue.
He believed that the unconscious mind consisted of three components: the 'id' the 'ego' and the 'superego.' The 'id' contains two main instincts: 'Eros', which is the life instinct, which involves self-preservation and sex which is fueled by the 'libido' energy force. 'Thanatos' is the death instinct, whose energies, because they are less powerful than those of 'Eros', are channeled away from ourselves and into aggression towards others.