The book of V.P. Zubov was first published in 1961 in large circulation and received international recognition. Over time, it became a bibliographic rarity. This publication is supplemented by a biographical sketch about the author, written by his daughter, candidate of art history M.V. Zubova, and one of the last articles by V.P. Zubov "The Sun in the Scientific Work of Leonardo da Vinci," not published in Russian during the life of the author. The book traces the main events of Leonardo's scientific life, the path of Leonardo's thought movement from a certain general to examples and again to general judgments. For all interested in Leonardo da Vinci and the development of scientific ideas in the Renaissance.