Freud's relationship with Rolland began in 1923 when Freud was sixty-seven years old; Rolland was ten years younger. Freud admired Rolland but his exchanges with him were marked by personal frictions which the author attributes to Freud's inability to separate people from their ideas. Their controversies over religious sensation, mysticism, and psychoanalysis derived from differences in personality and from divergent cultural backgrounds. Freud was central European and Jewish, influenced by nineteenth century evolutionary and rationalist traditions; Rolland was French and Catholic, a historian, musicologist, artist, novelist, and biographer of epic heroes. Five unpublished letters from Freud to Rolland, which the author discovered in the course of his research on the Frenchman, add special interest.