MARCEL DUCHAMP : “Nu descendant un escalier nº2”, 1912-14 - oil on canvas, 146- 89 cm. - Philadelphia Museum of Art (www.philamuseum.org)

One of the most audacious and intelligent paintings of the 20 th century. Duchamp's nus are half-cubist, half-futurist, even half-dada icons, in which the multiplication of points of view suggests a fantastic sensation of movement. The interpretation of the human body as a moving machine is a purely futurist idea in which the development of the chronophotography and the beginnings of the cinematography played an important role. Shortly after these compositions, Duchamp would begin his dada period, with his famous ready-made and his iconic urinals .