In addition to his activities as a composer, Leos Janácek was a prolific literary personality whose works include not only letters, feuilletons, criticisms, autobiography, ethnographic and pedagogical studies but also numerous articles dealing with music theory. They are unique documents, stimulating, diverse, exciting, and sometimes bewildering, they reflect Janácek's intense involvement with contemporary trends in philosophy, ethnography, physiology, and music theory, and his struggles in these worlds; yet they can hardly be found on a single bookshelf outside the Czech Republic (From the Introduction).