Final answer:
Sigmund Freud decided to analyze his own unconscious mind in 1896, advancing the method of psychoanalysis and the study of the human psyche.
Step-by-step explanation:
In 1896, upon his father's death, Sigmund Freud decided to analyze himself, becoming the first person to systematically investigate his own unconscious mind. Freud's approach to exploring the human psyche, which included techniques like dream analysis and free association, became foundational in the creation of psychoanalysis. This was a radical innovation in understanding mental processes, positing that much of our mental activity takes place outside of conscious awareness. His theories suggested that the unconscious mind harbors deep-seated desires and memories which significantly influence our behavior and personality.
Freud's work has had a profound impact on the field of psychology, particularly through concepts like the id, ego, and superego, and his theory of psychosexual development. Even though some of Freud's ideas are controversial and debated to this day, his influence on the study of the mind and the development of various therapeutic practices cannot be overstated.