A provocative exhibition runs at Dulwich Picture Gallery  until 25 September. It's the brainchild of Tate Modern curator, Nicholas Cullinan, who had of the novel idea of juxtaposing paintings, drawings and sculptures by Cy Twombly with paintings and drawings by Nicholas Poussin. The resulting show is called "Arcadian Painters". And this unusual, yet compelling, coupling is justified, says Cullinan, by the American Twombly's and Frenchman Poussin's mutual devotion to classical antiquity.
Twombly and Poussin are, in many ways, unlikely bedfellows of course. Poussin's restrained classical art is encrusted with the patina of time, seeming to belong on the walls of the discreetly lit, apparently conservative gallery in this leafy part of south London. Twombly's work, on the other hand, is a distant and unruly relation to Poussin's, with its Abstract Expressionist motifs and graffiti scrawls. But Cullinan has a canny eye and has used the rapprochement between the two painters to pull off a daring curatorial coup.
It was Twombly who claimed, "I would like to have been Poussin, if I'd had a choice, in another time". Both painters were to arrive in Rome at the age of 30, a city that would be Poussin's base until his death in 1665. After he'd become established there, his artistic production was to follow along tried and tested Italian guidelines. At Dulwich there is a sensuous and poetic Titianesque canvas by him, The Arcadian Shepherds, from 1628. Poussin's Arcadians, though, attend not to their flocks but to a tomb inscription. This picture provides a clue to the direction his art was to take, text being a constant undercurrent in his work, Poussin's "mute art" constituting a self-contained pictorial equivalent to his verbal thinking.
Three centuries later, Twombly was to arrive in Italy via that hotbed of the American avant garde, Black Mountain College, North Carolina, where he befriended the painter Robert Rauschenberg. Whilst he acknowledged his debts to both Pollock and de Kooning, Twombly's sweetly anarchic temperament drew him to to elements of surrealism and Jungian notions of "myth". The influence of the surrealists' "automatic writing" led him to let his hand run loose, resulting in the lyrical pencil arabesques that make up two sheets of drawings, from 1956, on display at Dulwich. Indeed, Twombly was to become something of a writers' painter: John Berger, for instance, enthused over the quotes in Twombly's work.
The histories and legends of Ancient Greece and Rome provided Poussin with a criterion against which he could gauge his own artistic ambitions. Conversely, for Twombly, his incessant quotations of the art and literature of the past was one of the reasons he was to find himself rehabilitated by post-modernist critics in the 1980s. He has remained centre-stage ever since.
The success of this exhibition can be seen by comparing two of the pictures on show: Poussin's The Triumph of Pan (1635) and Twombly's collage Pan (1975). Twombly is seen here feeling his way around classical subjects and his adopted terrain of Italy, whilst Poussin reveals himself to be one of the genuine greats of western art. Yet they're not offered to us as direct visual analogues for comparison, ancient and modern treatments of the same theme. Rather, Twombly's pictorial frisson and vitality riff playfully off Poussin's impeccable colour and robust composition, bringing out unexpected and fresh meanings in both. That's why this exhibition is such fun, allowing the viewer to join the dots for themselves.