On this day, 169 years ago, May 6, 1856 (April 3, 1856 in the lunar calendar), Freud, an Austrian psychiatrist and founder of the psychoanalytic school, was born. Sigmund Floyd (1856-1939), an Austrian Jewish psychiatrist and founder of the psychoanalytic school, was born on May 6, 1856 in Freiburg, Moravia. He moved his family to Vienna at the age of 4. He entered the University of Vienna to study medicine in 1873 and received his doctorate in medicine in 1881. In 1882, he collaborated with psychiatrist J. Bloyle to use hypnosis to treat and study hysteria. Between 1885 and 1886, he first went to Paris to study at J.M. Shaker, and then to Nancy to visit hypnotherapy. After returning to Vienna, he realized the limitations of hypnotherapy, and after 1895 he switched to his own original psychoanalysis or free association method to explore the concepts and desires that patients had forgotten, especially childhood. In 1909, at the invitation of S. Hall, President of Clark University and famous psychologist, he went to the United States with Jung and others to attend the 20th anniversary of the school, and met with famous American psychologists W. James, E.B. Titchener, J. McK. Carter and others. delivered a speech on the theme of psychoanalysis and became famous. During and after the First World War, he continuously revised and developed his theories, proposing important theories such as narcissism, the instincts of life and death, and the three-division structure of id, ego, and superego, making psychoanalysis a way to understand the motivations and personalities of all humans. In the 1930s, his theory reached its peak. In 1930, he was awarded the Goethe Prize. On his birthday in 1936, he was honored as a member of the Royal Society. He fought oral cancer in the last 16 years and kept working. Under duress from the Nazis, they were forced to leave Vienna for London in 1938. He died of cancer in London on September 23, 1939. His main works include: "Analysis of Dreams","Psychological Pathology of Daily Life","Introduction to Psychoanalysis","New Edition of Introduction to Psychoanalysis", and "Autobiography of Freud".