It is all, says the curator, about dialogue. Works of art in Tate Britain's fourth triennial are placed so that they can speak to one another. (Not vocally speaking, obviously, although there is one terrifying use of larynxed animatronics.)
It is also all, says the curator, about Altermodernism (read its manifesto here). Two steps beyond miserable modernism, one step beyond miserable post-modernism, joyful altermodernism sits, embracing global cultures and new media.
From the improbably-named Spartacus Chetwynd's video installation across a dozen screens to the grave photogravures of Tacita Dean, via Navin Rawanchaikul's epic Bollywood-style painting and Shezad Dawood's ecumenical DVD, all continents and forms are examined in a show which embraces the vibrant and difficult.
Nicolas Bourriaud, the aforementioned curator, has wrenched what he hopes will be the next movement in art out of the pasty hands of westerners and into those of the rest of the world. This is better in theory than practice, of course: at least half the 28 artists work in London, and several more in New York. Talent from elsewhere, while not lacking on the arts scene, has largely not made it into Tate Britain.
The best room in the show is in fact the work of one Englishwoman and one Scotsman. Tacita Dean has made photogravures of funerals and scenes of devastation, then written over them (as is her way) as if to suggest they are stills from a movie. The darkness (metaphorical and visual) of the images, their sombre tones, their stillness all touch the heart.
At the other side of the room is Charles Avery, whose art all stems from a fully-realised fictional world - not just geography but culture and society. There is a black and silver swirling map of this world, complete with imagined place names and a delicate topography. There is a sculpture of an imagined creature too, which resembles a duck whose bill is another duck; this 'Aleph Nul' (to the right) is just one of the animals which populates the world (and Avery's mind). Along with some deft drawings, you become instantly immersed in this world and begin to ask why it is any less real than the real world. After all, much of this world is as we would like to imagine it, rather than as it is.
The photos of Darren Almond are peaceful landscapes, taken with 15-minute exposures; they are just as restful on the brain as they are on the eyes. Inversely stimulating is Navin Rawanchaikul's triptych, which looks like a Bollywood billboard and is painted in joyful colours, with beautiful Hindi script snaking along in pastels and vibrant blues. The simple appearance belies its complex exploration of alienation from one's culture (Rawanchaikul works in Japan and Thailand) - this movie is one of dreams lost, rather than realised, on celluloid.
It is stretching it somewhat to claim that these are the up-and-coming heroes of modern art - Tacita Dean is a long-established figure. Nevertheless, it provides an interesting survey of the landscape, eliciting hints about the future of modern art. Post-altermodernism, anyone?