Recently I was having a water-cooler conversation with my colleague, the Arts Guru. We weren't gossiping about our new Star-Trek-like newsroom, which comes complete with red “hot” seats for news editors, but about an article AG had just written on a man called John Myatt. Myatt is a master forger – he makes Monets, Picassos and Modiglianis – whose works have become eminently collectable. I wanted to know what AG thought of this development. He pulled a face, then said: “The people who buy them can't possibly think visitors will think they have real Monets in their house ... can they?”

We looked at each other. Can they? It depends. If I had a Monet on my wall, no, but if Bill Gates had one ... Put another way: I know plenty of wealthy women who carry fake Hermès bags or wear fake diamond jewellery, but because they could buy the real stuff if they wanted to, their friends assume it's genuine. And though, if asked straight out, they wouldn't deny the provenance of their goods, they don't exactly advertise it either.

But I also know women who do advertise it, because 1) they want people to know they would never spend that much money on something as frivolous as fashion; and 2) the postmodernism of it all appeals to them.

It's not that different from people who own Andy Warhol or Marilyn Monroe prints that came not from the Factory but from a renegade group who took the silk screens to Europe and produced multiple copies stamped “Sunday B. Morning”, with another space for “Fill in Your Own Signature”. If Richard Prince, who is having a retrospective at the Guggenheim museum in New York, can “rephotograph” a photograph and present it as original work, if Gus Van Sant can do a frame-by-frame remake of Alfred Hitchcock's Psycho, why not “reproduce” a handbag and present it as an homage?

The fashion world is tying itself in ever-more elaborate knots over the issue of copying. This is not the same as counterfeiting, which is the overt creation of a fake product that purports to be the real thing, and involves patent and trademark infringement and is actionable – think fake Chanel bags and Cartier watches and police raids on warehouses in New York and China – but rather similar-but-slightly-different, usually cheaper, pieces. The kind of thing you see in Marie Claire magazine's Spree v Steal feature. The kind of thing H&M has made a virtue of by “collaborating” with designers on limited-edition lines that look very much like the designer's main lines but cost a fraction of the price.

Put another way, if Roberto Cavalli doesn't have a problem being “inspired” by the leopard-print dresses in his main line to create a similar, much less expensive leopard-print dress for H&M, why should consumers think it is wrong for other lines to do the same thing? Is Lucien Pellat-Finet's skull-studded version of a Chanel knit jacket brilliantly tongue-in-chic or a knock-off? (Personally, I think the first.) Can anyone actually claim to have invented the baby-doll dress?

There is a bill making its way through the US Congress known as – surprise! – the Design Piracy Prohibition Act, which would amend the Copyright Act of 1976 by extending copyright protection to fashion designs for a period of three years (at which point, presumably, they would either be so over everyone would have forgotten them, or so over they would have come back in, at which point they could be re-copyrighted).

The Council of Fashion Designers of America is all for it. But as Kal Raustilia of UCLA and Christopher Sprigman of the University of Virginia point out, in an article in the Virginia Law Review: “Where IP Isn't” (IP being intellectual property), high street copying helps force designers to reinvent themselves, which speeds up the fashion cycle, which increases their sales, leading to greater creativity and productiveness. In other words, copying is good.

Didier Grumbach, the president of the Chambre Syndicale de la Haute Couture in Paris, disagrees, and blames the current spate of sartorial imitations on the internet and the speed at which fashion show pictures zip their way around the world. His solution is to ban e-photographs until the clothes are ready to go into stores, as opposed to posting them the season before, which might sound like good news for fashion houses – except no designer will countenance such a ban because of the amount of free advertising sites such as Style.com provide. As Calvin Klein pointed out a long time ago, to be widely copied simply means you are widely successful. It's when you stop being copied that you should worry. You know the cliché: imitation is the highest form of flattery.

It all comes down to what originality means. Maybe fashion people should take a page from Myatt, who labels his works JMGF, or John Myatt Genuine Fakes – which is a amusingly original way of approaching an unoriginal act. After all, haute brands are continually citing their influences, as Robert Duffy, Marc Jacobs' business partner, pointed out recently in response to charges that Jacobs' work was derivative of Comme des Gar?ons and Martin Margiela. Why shoudn't the high street directly admit its debt to high fashion? Everyone would benefit: the copied by the acknowledgement of superiority, and the copyist by adding a knowing wink to a label and thus transforming, say, the sleeveless belted silver sequinned black wool dress from Principles that is very-similar-but-not-the-same as the sleeveless belted silver sequinned velvet dress from Alberta Ferretti into a party-perfect romp through our comment-on-the-comment culture.

It's the natural conclusion of what fashion teaches: the whole point of clothing is to advertise a certain value system in a commercial and accessible way. Once you do, the object becomes covetable and – just possibly – collectable