The German Carl Einstein (1885-1940) was one of the first and most outstanding theoreticals of the artistic avant-garde twentieth century. Critics and nothing complacent, their analyzes contributed to delimit our understanding of cubism, surrealism or, as in this text, of the painting proposed by the so-called "German expressionists": a heterogeneous group of artists that encompasses from Emil Nande to George Grosz, Going through Ernst Kirchner, Oskar Kokoschka or Max Beckmann.