Will Self: are the hyper-rich ruining the new Tate Modern? I blame it all on Marcel Duchamp - for reasons I'll make clear in the appropriate place; in the meantime, let me say I have irrationally fond memories of Bankside Power Station. I worked in Southwark in the late 1980s, and when the weather was fine my colleagues and I would eat our lunch on the embankment in front of the old hulk. It had ceased generating electricity almost a decade before, and while its soft-modernist brick shell was still perfectly intact, great shocks of buddleia thrust out from the walls, while a fringe of shrubbery flopped over the roofline, mimicking the hairstyles of the period. If my buddleia-tinged memories seem irrational, it's because the inner London of that era was pretty run-down, with derelict buildings, overgrown plots and a pervasive griminess - the sooty sediment lain down by coal fires, domestic and industrial. Yet something was afoot: there was rumbling under the arches around Clink Street, and Borough Market was beginning its mutation from a wholesale fruit-and-veg outlet into a retail chorizo and frothy coffee one. Walking on an unseasonably hot late-October morning from Borough tube station to my former picnic spot, I was struck by the way the radical transformation of the area has been achieved incrementally over the last quarter-century: the years pass, brickwork is repointed, new builds go up, plate glass shines, bridges wobble across the Thames, and suddenly, hey presto! We have the Tate Modern complex that we know and, arguably, love: a dense huddle of constructivist and bar-code-facade office and apartment blocks now surround the former power station, each one equipped with its own stylish eatery or specialist coffee shop; and then there's the art gallery itself, recognisably the Bankside of yore - because what the architects Herzog & de Meuron did was effectively the country's biggest loft conversion - but what was this grouted to its blocky flank? It looks like one of those interstellar spaceships made popular by George Lucas in Star Wars: curvilinear and broadly speaking conical, yet asymmetrical, with an irregular patterning of windows let into its hard hide referencing either arrow-slits in medieval fortifications, micro-circuitry writ very large indeed, or both. Tate Modern complex ... "Like one of those interstellar spaceships made popular by Star Wars" It was, of course, the new Tate Modern extension, slated for completion in 2016, and I was en route for a preview visit. Who would begrudge Nicholas Serota and his arty empire this latest territorial expansion? After all, as Kerstin Mogull, the Tate's managing director pointed out when I arrived at Level 4: the gallery currently has 5 million visitors annually, twice as many as originally anticipated, and twice as many as visit the Museum of Modern Art in New York. We all know it's true - we've all been to popular shows at Tate Modern where visitors have had to wheel about, like aesthetically crazed musk oxen, in the crowded space. Yet space is what Tate Modern has really always been about: the dramatic walk down the long smooth ramp into the old turbine hall is an essential prelude to the rest of the experience, for here the wannabe art-appreciator is made to feel small and insignificant - as an ancient Babylonian might be on approaching the throne of Nebuchadnezzar in similarly monumental surroundings. The new Tate Modern extension will boast six new levels: two for education and community outreach, two for new galleries and two for a restaurant, a cafe, the merch" and general arty grooving. A new entrance is being contrived on the south side of the building. The aim, Mogull told me, is to open out the Tate's collection to more global influences; there's a recognition that in the past things have been too northern hemisphere, so now acquisitions committees are at work in Africa and Asia sourcing the finest of contemporary art with which to stock the finest of new galleries. It's a beguiling prospect, not least - as I told her - because the galleries in what we must, perforce, call the old Tate Modern, aren't really that much cop. An ode to space ... Turbine Hall, Tate Modern. Photograph: Robert Harding World Imagery /Alamy No, really: I mean it. The main public galleries in Tate Modern are at once vast and claustrophobic, the worst offenders being the ones at the west end of the building and at the front. Counter-intuitively, the best spaces are at the east end and lack natural light. Overall, the huge success of the enterprise rests less, I would argue, on traditional curatorial values such as the creation, maintenance and display of the canonical, than on reliably offering the sort of wow factor that other large-scale tourist attractions provide. The special commissions for the Turbine Hall, and the location itself, which offers a frothy coffee stopover for those shuffling around the stations of London's cultural cross, are what ensure a roaring cataract of punters. A charitable view would be that the Tate Modern was housed in a structure designed to generate power not epiphanies. Besides, as a gallery displaying modern and contemporary work, the traditional requirements for showing easel painting and the plastic arts do not apply - this is a post-industrial space for post-industrial, multimedia art: performance and video installation do not, of necessity, require cloistral and uniformly lit environments. But another way of seeing this is that, while the old values enshrined in the art gallery no longer apply, there is a more atavistic sense in which Tate Modern is true to its origins. The art gallery evolved from the enclosed promenades of aristocratic country houses, the paintings were hung as an artificial prospect for ladies and gentlemen too refined to venture outdoors. As they wander about Tate Modern's angular volumes, and in due course trip across the aerial bridge connecting to the new Tate Modern, latter-day strollers will be diverted by flickering VDUs and quizzical objets d'art. They are the inheritors of a tradition that's no longer financed by rentier incomes - at least, not directly. There's no doubt that Tate Modern is a going concern: 70% of its operating costs are self-funded, and only 30% comes from the public purse; huge donations from private individuals have been sucked in through the arrow-loops of the new carceral extension. Exactly how these rich folk made their money can only be a matter of speculation. Most of the new mega-structures powering skywards in central London are the product of what's termed "flight capital": money extracted from less-developed economies, that's come looking for a high-return home. Some of this flight capital is invested in British cultural capital - a prime example would be Alexander Lebedev's newspaper interests, and the return expected from it comes in different forms: favourable tax regimes, state honours, citizenship etc. It would be wise to view the Tate Modern in this rather less rose-tinted uplight: as simply another spatialisation of the savage inequality that's coming to typify 21st-century London. Working people on modest to low incomes and the unwaged may no longer be able to afford to live in the city, but their children can at least get to experience for a few hours the aristocratic lifestyle of strolling about and looking at expensive stuff. The Physical Impossibility of Death in the Mind of Someone Living, by Damien Hirst. Photograph: Graeme Robertson/Graeme Robertson And it is expensive, this stuff: the contemporary art market is grotesquely overvalued; the relationship between the aesthetic value of works by big-name international artists and the sums they fetch at auction is tenuous at best. No, as in every other area of our benighted lives, the demented piper of the market calls the tune. Last year I attended Grayson Perry's first Reith Lecture, which was delivered at old Tate Modern to an audience of the financially great and the culturally good. Perry, wearing one of his signature dresses, gaily pronounced that 90% of the contemporary stuff on display in galleries was "crap," but remained Panglossian, for, in the best of possible worlds - this one! - time would sort out the wheat from the chaff. Unfortunately I cannot agree with him, for reasons that were also made clear during the Q&A session following the lecture, when from the floor Serota admitted, quite cheerfully, that he had accepted on behalf of the Tate the gift of Damien Hirst's The Impossibility of Death in the Mind of Someone Living (aka, the stuffed shark). Public galleries have often accepted artworks as donations, but in the 1990s they began accepting such donations from the artists themselves, and then putting them on display. This represented a flagrant disregard for curatorial standards, and registered the exact point at which the hyper-rich artists and their still more moneyed dealers began to call the tune - henceforth the "crap" silting up public galleries would be deposited there by the ebb and flow of finance rather taste. But really, as I said at the outset, I blame Marcel Duchamp. His four signature works of the 20th century: Nude Descending a Staircase No 2 (1912), Fountain (1917), The Bride Stripped Bare by Her Bachelors, Even (The Large Glass) (1915-23), and La boîte-en-valise (1941), represent the response of an artistic genius to the problem of the artwork in an age of mechanical reproduction. What Duchamp - unlike Perry - understood, is that the gallery is fundamentally otiose once easel paintings and sculptures cease to be meaningfully unique objects: because if they're capable of reproduction, what need is there for a unique place, time and space in which to display them? Fountain (1917) by Marcel Duchamp. The new Tate Modern will thus be not an art gallery per se, but a sort of life-size model of what an art gallery might be should our culture have need of one. Since it doesn't, but rather has a requirement for visitor attractions that reify the ever‑widening gulf between haves and have-nots, I'm absolutely certain it will prove an outrageous success.