French artist, he wanted his works to be in harmony with nature and would rather the term concrete art than abstrait art to qualify his work. Very avant-gardist, from 1916 to 1920, he participates in the Dada movement in Zurich and presents abstrait works on (polychromed) wood, paper, marble and stones. He also gives poetic titles to his works. From 1931, his round-bump sculptures became the symbol of the XXth century's abstrait art. He is considered as a master of this artistic movement.