Duchamp was born in France, but lived for much of his adult life in America. In 1911 he was painting in a cubist style, but he virtually stopped painting after 1912. Duchamp was intrigued by the idea that ordinary, mass-produced things could be considered as art objects in their own right. He preferred simply to sign, and sometimes alter, household objects, terming them 'readymades'. On moving to America in 1915, Duchamp became a leading figure in the New York Dada group, along with Picabia and Man Ray. His questioning attitude towards definitions of authenticity, originality, artistry and authorship has been immensely influential.