"Tens of thousands of books appear in this photograph of the interior of the sculpture Idiom, by Matej Krén. On page 176, Jean Baptiste Michel et al. describe an even larger collection: a 5.2-million-book corpus containing 4% of all books ever published. Statistical analysis of this corpus makes it possible to study cultural trends quantitatively. Original sculpture (Municipal Library of Prague): Matej Krén/Photograph: Zdeněk Urbánek"