Freud's psychoanalytic theories 'The Unconscious Mind'
Sexual instincts or drives have deeply invested roots in the unconscious mind. Instincts act by giving vitality and enthusiasm to the mind through meaning and purpose. The ranges of instincts are in great numbers therefore Freud expressed them in two categories. Eros is the self-preserving life instinct containing all erotic pleasures. In contrast, thanatos is the death instinct full of self-destruction of sexual energy. The main part of human behavior and actions is tied back to sexual drives. Since birth the existent of sexual drives can be recognized as one of the most important incentives of life.