Fountain

The object is a readymade: a manufactured thing chosen rather than made by the artist. Duchamp's point was that the choice was the art, and that a museum could turn anything into a sculpture by putting it on a plinth. Look at how the urinal, lying down, becomes a smooth abstract form, a shape that critics of the time compared to a seated Buddha or a Madonna. The signature is a joke on the manufacturer's name, Mott, and on a comic strip character, and the title turns a receptacle into a fountain, source rather than drain.

The original vanished almost immediately, and only Alfred Stieglitz's photograph of it survives, which is the image shown here. In nineteen sixty four Duchamp authorised the Milan dealer Arturo Schwarz to make an edition of replicas from that photograph, and Tate's is one of them, acquired in nineteen ninety nine. In two thousand and four, five hundred art professionals voted it the most influential artwork of the modern era, ahead of Picasso. Conceptual art, Pop art and much of what you will see upstairs begins with this object.

Did You Know? Only a photograph by Alfred Stieglitz records the original of nineteen seventeen; every Fountain you can see today is a replica made almost fifty years later.