This Volume II of the Proceedings of the Worldwide Music Conference 2021 continues the line of publications of the first volume in a highly interdisciplinary mode. This time, we offer eight chapters that provide the in-depth study of music in four large sub-fields: mathematics, language and theory of narrative, evolution and perception, and, finally, sociology. The first chapter, by Roman Ruditsa, is devoted to the study of structural pitch organization. This is based upon a formal logical interpretation of the idea of pitch. The chapter contains formal definitions of such objects as tones, intervals, and interval systems and a demonstration of the logical relationships that exist between them. The second chapter, in the same mathematical venue, by Celina Richter and Stefan E. Schmidt, revisits the millennial question of the essence of an interval, using highly advanced mathematical language, the categories of monoid and the algebraic theory of measurement. The next block is dedicatedto language and narrative; the first chapter is by Vincent Meelberg. Here, the reader will find fascinating developments in the ongoing deliberations on this elusive category. The name of Trevor Rawbone, perhaps, does not need an introduction to those involved with cognitive studies of music. This time, his chapter deals with the idea of the language of musical thought, which shifts the traditional discussion of language into a very new dimension. Carlos Almada begins a new section in the book, the one dedicated to evolution and perception. He begins with Darwin and takes us through the exciting path of development of the science of evolution, which he masterfully connects to his model of derivative analysis of music. The question of psycho-physiological foundation of the ethnic hearing, raised in the chapter by ?lla V. Toropova and Irina N. Simakova, is a difficult one. The idea of ethnic character of music had been a part of traditional musicology and usually was expressed in specific language of humanities. The chapter by Daniil Shutko on the theoretical ideas of the legendary professor of St. Petersburg conservatory, Dr. Tatiana Bershadskaya, was difficult to put into any category. Her concept of music was truly universal and interdisciplinary. At the same time, the concept and Shutko’s description are as closely focused on music theory in a narrow and precise sense as possible. The art and culture of consumption of wine in correlation with the choice of music for listening is a theme for a true connoisseur. It becomes even more intriguing when the authors, Diego Pérez-Fuertes, Emma Juaneda-Ayensa and Cristina Olarte-Pascual, add to the discussion the special circumstance of the pandemic and the way human spirit meets this challenge in the most graceful way.