Mathematics, anatomy, mechanics, hydraulic engineering, military art, aircraft engineering and architecture - this is not a complete list of Leonardo da Vinci's scientific interests. On the pages of the book, Leonardo's research and discoveries in these areas are compared with the achievements of subsequent eras. And the conclusions are often not in favor of contemporaries. The theoretical justification of the genius of discoveries is supported by quotes from the master, numerous original drawings, reproductions of paintings and three-dimensional models created in our time.