Sigmund Freud, who died 40 years ago, spent nearly half a century living and working at 19 Berggasse in Vienna's Ninth District - right up to the year before his death at 83, when he fled to Paris and then settled in London as Nazi troops swept into Austria. He fathered six children, wrote books that would reshape man's understanding of man, analyzed patients couchside from morning to night, researched the wonders of cocaine, met with a discussion group that included Alfred Adler and Carl Jung, and made the Oedipus complex and penis envy household words. Today, the apartment/office is a museum/library - without the couch. About 10,000 Freudian pilgrims find their way to the Sigmund Freud House every year.

Opened to the public eight years ago (after Americans, in a survey sponsored by the Austrian government, had voted Freud the best-known Austrian, over Mozart. Schubert and Hitler), the Sigmund Freud House attracts devotees who in true Freudian fashion seek the inner workings beneath the external trappings.

The visitor finds, if not the secret to the man historian Michael Hart recently called the 32nd most influential person in history (ahead of Alexander the Great and behind Orville and Wilbur Wright), a foyer, waiting room, consultant room and study. The 800-odd books once in Frued's study were sold in 1939 to Dr. Jacob Schatzky, then the librarian of the New York Psychiatric Institute, for $500. He bought them from a Viennese bookseller, and today they remain secure and accessible to scholars at Columbia University's Health Services Library in New York. Freud's couch is in the London home of his 83-year-old daughter, Dr. Anna Freud, along with other furnishings from the consultation room.

The waiting room at the Sigmund Freud House, however, has the furnishings used by the world's first - and for a long time only - psychoanalytic society, Freud's Psychological Wednesday Society. The society, founded in 1902, later (1908) developed into the Vienna Psychoanalytic Society, which in turn became the International Psychoanalytic Association (1910).

The more recent Vienna-based Sigmund Freud Society not only runs the Sigmund Freud House but, as a spokesman puts it, "contributes to the presentation, research and information on Freud's life and work, and on the history of psychoanalysis." Working with the still-active Vienna Psychoanalytic Society, the Sigmund Freud Society, founded in 1968, also "informs on the new scientific findings in applied psychoanalysis through lectures, seminars and publications."

The society's task of promoting Freud will not be made easier by some current attitudes toward psychoanalysis in the United States, where the method long has found willing practitioners. In a recent cover story titled "Psychiatry on the Couch," Time magazine said that "Psychiatry, especially analysis, is now suffering a bad case of midlife blues."

Acknowledging that the effectiveness of Freudian therapy remains a topic of lively debate among professionals, it cited a 1976 American Psychoanalytic Association survey that found the average psychoanalyst - and only 10 percent of U.S. psychiatrists consider themselves Freudian psychoanalysts - has 4.7 patients on the couch, down from an average of 6.2 under treatment in 1966.

Freud's theory of the mind is "dazzling and complex . . . one of the great intellectual triumphs of our time," Time said. But it said that some critics predict nothing less than the extinction of classical psychoanalysis in the near future.

Society members and Austrian government officials often have criticized Austria's failure to pay homage to Freud until 32 years after his death with the opening to the public of the Sigmund Freud House.