Cubism Cubism", (from 1909 to 1914) during which time Juan Gris emerged as an important exponent (after 1911); and finally Cooper referred to "Late Cubism" (from 1914 to 1921) as the last phase of Cubism as a radical avant-garde movement. Douglas Cooper's restrictive use of these terms to distinguish the work of Braque, Picasso, Gris (from 1911) and Léger (to a lesser extent) implied an intentional value judgement. Cubism burgeoned between 1907 and 1911. Pablo Picasso's 1907 painting "Les Demoiselles d'Avignon" has often been considered a proto-Cubist work. Georges Braque's 1908 "Houses at L’Estaque" (and related works) prompted the critic Louis
Czech Cubism secessionist designers such as Otto Wagner and Jan Kotěra. Architects such as Josef Chochol and Pavel Janák devised spiritualist philosophies of design and a dynamic ideal of planar form derived from cubist art. As Cubism spread across the European continent in the early 20th century, its greatest impact can be seen today in the Czech Republic. Pyramid and crystal forms were one of the signature principles seen in Czech Cubism which was incorporated in architecture, furniture, and applied arts. The Museum of Decorative Arts in Prague (UPM) uses the House of the Black Madonna as a permanent exhibition space for