The event, which could be seen as a kind of Rubens revival, has been organised by the Fat Women's Group. Their celebration of fatness includes pictures, prints, videos and artefacts which demonstrate "the beauty and reality of larger sizes".
"You only have to look at how many lovely representations of fat women we have managed to gather together to see that beauty and thinness do not necessarily go together," said Janet Mearns, a member of the Fat Women's Group, which was founded eight years ago.
Today, the group will also be handing out awards to fat women who have "taken a risk to promote size acceptance". Among the winners is Helen Jackson, a barrister who campaigns to end size discrimination, Sue Surry, who promotes Big Aerobics, and Laurie Toby Edison and Debbie Notkin for their book, Women En Large, which "tells the stories of real life fatsos in words and photos".
Ms Jackson, who practises in Birmingham, says she has come across cases of 101/2-stone women being turned down for jobs on account of their size. It is a situation she is desperate to change. "I want to make discrimination against fat people as unacceptable as discrimination against gay people."
Susie Orbach, 47, a psychotherapist who founded the Women's Therapy Centre in London and wrote Fat is a Feminist Issue, last night expressed concern that the "fat aesthetic" would be substituted for the "slim aesthetic". She advocated "multiple images of women and men represented in a whole range of sizes instead of one size".
Successful fat women do exist. Most recently, Jennifer Paterson, a freelance cook and Spectator columnist, and Clarissa Dickson Wright, a former barrister turned Edinburgh cookery bookshop owner, burst on to our screens with their weekly BBC2 cooking show, Two Fat Ladies.
Larger than life characters such as Vanessa Feltz, the chat-show host, and the comediennes Jo Brand and Dawn French are outspoken on the subject of size and make no bones about their bulk. Ms French has been involved in a north London shop which sells clothes for larger women.
More often than not, however, women succeed in spite of their size. According to Ms Jackson, society is becoming increasingly biased against overweight women. "It's far more widespread than we realise," she said. "People who 10 years ago wouldn't have been told they were fat are now being discriminated against." She has problems persuading anyone to take up their case in the courts. "One of the problems is that many people think it's a matter of shame to be excluded on account of one's weight."
Ali Farrelly, 30, a fat women's fashion stylist and member of the Fat Women's Group, is also exhibiting her work today. As part of her crusade against "body fascism", Ms Farrelly plans to reshoot classic advertisements such as the Calvin Klein photograph of a naked Kate Moss using women double her size, but she is worried about copyright.
"If I use the name, Vogue, with a size 20 model, they are going to sue the pants off me. I'll have to say it's an 'art project'. I'm sure Andy Warhol didn't get sued by Campbells."
As large as life...
They say that inside every fat person there's a thin person waiting to get out; that's because we've just eaten him.
The critics say I'm so fat that I fill the screen and there's no room for guests.
There's something more alluring ... about our full and splendid bodies that shouldn't be ignored.
She fitted into my largest armchair as if it had been built round her by someone who knew they were wearing armchairs tight round the hips this season. PG Wodehouse, Jeeves and the Unbidden Guest