The article by S. Belyakov, a historian, literary critic and author of several non-fiction books, mostly deals with the ‘Moscow period’ in the life of Georgy Efron, the son of M. Tsvetaeva. According to Belyakov, Georgy was a bookish boy in every sense of the word: his opinions, knowledge about life, and preferences and interests were largely defined by what he had read. Mur (his nickname) fascinates not only as the poet’s son but also as a young erudite and intellectual, immortalised by the diary he left behind, which contains precious descriptions of daily life in the 1930s — 1940s. In his examination of the books and periodicals in the scope of Georgy’s reading interests (from European classics to Mickey Mouse comic books, and from Silver Age poetry to latest Soviet novels), Belyakov discovers that Efron’s reading and his comments on it alone help to reconstruct many aspects of his personality, while the numerous quotes from Georgy’s diary allow for appreciation of his erudition, critical treatment of reality, and writing style.