Twenty club players and artists have been invited to the Gallery “CALIBRE 33 is it art?” to play matches of chess as part of the concept “Chess therapy.” The twenty players would make their respective moves, and each time I came to one, I would respond immediately and move on to my next opponent. This continued until the end of the matches, whether they ended by abandonment, by dullness, or by repeating the same move three times resulting in naught. The twenty matches have been won. The relaxed atmosphere of the Gallery drove me to develop certain aspects of my work which will then be built upon until today. Refining the playing conditions, playing always with the black pieces, bending the constraints of the game (time, competence of my opponents, number of participants...). The largest number of players met at once was 100 in Besançon in 1981.