Why did Marcel Duchamp's L.H.O.O.Q. cause controversy?

Marcel Duchamp’s L.H.O.O.Q. (1919) caused controversy because it was an irreverent act of defacement directed at one of the world’s most iconic paintings, the Mona Lisa. By adding a mustache and goatee to a postcard reproduction of Leonardo da Vinci’s masterpiece, Duchamp challenged the traditional reverence held for historical art.1

This act was central to the philosophy of the Dadaists, who sought to reject the art and cultural values of the past. In their view, the civilization that produced such revered art was also responsible for the horrors of the First World War, which had recently concluded. Consequently, Duchamp’s work served as a provocative critique of the status and sanctity traditionally afforded to classic works of art.1