The new issue of the journal "Philosophical Letters. Russian and European Dialogue" is dedicated to the Russian philosopher P. Ya. Chaadaev. The issue contains articles reflecting the relevance of the thinker's heritage, revealing new approaches to understanding his work. In the section"Archival materials. From unpublished", we continue to publish letters of the philologist O. M. Freidenberg, as well as publish the letters of the philosopher S. L. Frank to the psychologist and psychiatrist L. Binswanger. A new section of the journal "Memory of Culture" opens to the reader articles on collective memory and historical analysis of the work.