Herbert Bastian (Germany) devotes a large part of his spare time to studying the Chapais manuscript, a revolutionary manuscript for the game of chess in its day.
Let us leave the floor to Herbert Bastian:
I was then given the honour of reporting on the state of research on the Chapais manuscript, Mennerat's most important contribution to chess history. The chess-historical significance of the work is now well understood and will be described in my forthcoming book on it. Chapais coined the concept of opposition, which is extremely important for endgame theory, and was the first to use the multifunctional king movement (as I call it) in a whole series of examples, which only became generally known through the famous Réti study of 1921. Chapais was the first to study the endgame king and two knights against king and pawn, which Alexei Troitsky (*1866-†1942) later used as a model, and probably communicated with André Danican Philidor (*1726-†1795) about the endgame king, rook and bishop against king and rook. My investigations of various kinds have used a variety of clues that Chapais could be a pseudonym and in fact the famous French mathematician Gaspard Monge (*1746-†1818) is hiding behind it. Even if there is no 100% proof, the weight of circumstantial evidence is, in my opinion, overwhelming.
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