Marcel Duchamp was a highly influential French artist born in 1887 who worked in Dadaism and conceptual art. He helped define revolutionary developments in painting and sculpture in the early 20th century. Duchamp rejected "retinal art" meant solely for visual pleasure and sought to put art back in service of the mind. His works like Fountain and L.H.O.O.Q. challenged definitions of art by taking everyday objects and placing them in galleries. Duchamp created miniatures of his works in the Box in a Valise and influenced generations of artists through his experimentation and questioning of art.