Why the Turner prize must live on

The Turner prize needs saving. An article in yesterday's Independent on Sunday summed up savage criticism that has been levelled at this year's shortlist. The winner tonight - will it be Cathy Wilkes, Goshka Macuga, Mark Leckey or Runa Islam? - will have triumphed in one of the least appealing competitions the Tate gallery has ever staged.

There is something truly dull and depressing about this year's exhibition. The article in the Independent leaps to the not entirely unprovoked conclusion that the Turner has had its day; all the good artists have had the award and it's running on empty. Critics quoted in the article include veteran Tate-baiter Brian Sewell, who says they should put him on the jury to make it a real debate. Well, the Tate did invite me on the 2009 jury in spite of my love for old farts like Picasso, and I accepted - so it falls to me to fight for this institution's future.

The prize has big problems. But its decline is not the fault of Tate Britain's director Stephen Deuchar, who has now taken over the job of chairing the jury from Sir Nicholas Serota. No, the crisis has been a long time brewing. The Turner prize started festering nearly a decade ago, when Tracey Emin stole the show with her bed in 1999 but failed to win. Emin's fame and that of many other artists has since then mushroomed far beyond anything the Turner judges imagined back in those days. This has happened with no regard for whether they are any good. Is Marc Quinn's gold statue of Kate Moss, currently in the Greek galleries at the British Museum, a good work of art? No, it is rubbish, but who cares? He's famous ... far more famous than Pheidias whose works can be seen nearby, if you're interested.

The Turner has been outflanked as standard-bearer of the new by far less worthwhile institutions. The rise and rise of art as entertainment, the particularly silly department of Selfridges that is the Frieze Art fair, the vacant GSK Contemporaries - such marvels of our age drown the very idea of artistic merit. Bigness dwarfs virtue. Media exposure and money define what's big in art, and a very bad artist is as likely to have a South Bank show profile as a decent one. Badness can make you as famous as goodness, so why be good?

The Turner, by contrast, has a curious innocence about it: its unfashionable premise is that quality does matter. Some art is good and some is not. You can judge between good and bad video and conceptual art, just as you can between good and bad painting - and society is the better for insisting on that choice.

We are desperately in need of rediscovering the idea of quality; our visual culture must become more discerning. The Turner is the natural home of that spirit, and I hope next year it will come back with its critical guns blazing.