The ancient Greeks considered history to be an art, and even today the debate over how fair it is to call history a science does not abate. Of the three "co-authors" of history - Patterns, Personality and Chance - the historian is seriously able to study the "creativity" of only one - Patterns. To understand a Person, he will have to become a psychologist, or even a psychiatrist, and when faced with a Case, he is completely powerless. A case in history is akin to the well-known butterfly effect: it seems like a mere trifle - I stumbled, crushed a butterfly, and as a result the world changed its trajectory. The book by historian and publicist Peter Romanov is devoted to numerous accidents of Russian history.