Treasures on Earth by Keith S Thomson

Museums are a thing of the past, Mrs Thatcher told Stephen Bayley - but he can imagine their future

Life is lived forwards, but understood backwards. Hence, museums. Like the department stores they so much resemble, museums are among the most characteristic institutions of Western culture. Although the Vatican's Renaissance galleria (which gave its name to museums of art) and the cabinets of curios assembled by scholarly 17th-century exotics preceded them, museums as we know them are a product of 19th-century urban civilisation.

The similarities between, say, the Bon Marché store in Paris and London's Natural History Museum are revealing. In each, the the whole world is organised, categorised and put on display. Notions of hierarchy, judgement and value are shared by each. Stores have buyers, museums have keepers. The distinction that in one the merchandise was for edification and, in the other, for consumption only further emphasises the museum's roots in the equivocal value system of the Victorians. As C P Snow once remarked, the majority of what we call "traditions" were actually inventions of the second half of the 19th century.

I cannot (without the aid of hypnotic regression) ever forget the dreadful day at a fund-raising dinner for the Design Museum when the hostess, Mrs Thatcher in her full pomp, wagged her finger and imperiously said (in front of our amazed potential benefactors) that "Museums are things of the past". Yet, as a practical reality, the museum has never been so vigorous.

Since charges were dropped at the end of last year, the Victoria & Albert's admissions have increased 300 per cent. A vox pop conducted outside the Natural History Museum showed that a visit to the scriptural home of palaeontology was an attractive rival to EastEnders on a wet Sunday. There are about 15,000 museums in the US, 2,500 in this country: among the former, a museum of Spam in Minnesota; among the latter, one devoted to the curation of teddy bears. A successful new museum of art in Bilbao has recently transformed the economy of the entire Basque region.

So it is an odd, but interesting, time to publish Treasures on Earth: museums, collections and paradoxes, a revisionist tract by Keith Thomson, director of Oxford University Museum. Thomson, a life-time museum professional of exceptional distinction, has written a humane, elegant but sceptical account of the modern museum phenomenon, which he treats with a nicely regulated enthusiasm.

Like all museum administrators, Thomson inevitably tends towards a preoccupation with funding. His concern is that as new museums open, others shut. As a scientist, he is more inclined to cite Malthusian and Darwinian rather than Ruskinian arguments.

He says that we cannot continue to create museums willy-nilly when management resources are finite. That his remedial suggestion of selling off collections ("de-accessioning", in the cringe-making curatorial demotic) is presented as shockingly radical is mere evidence that museums are – rather as you might expect – intensely conservative organisations.

The heavy responsibility of conserving all our yesterdays produces an inevitable caution. Museums are the supertankers of culture: they take a very long time to change direction. The very use of the term "keeper" to denominate museum middle-managers suggests a costive, protective, inward-looking attitude. Worse, any belief that intimate daily access to great art is inevitably civilising would be seriously undermined by even casual appraisal of many museum staff.

Should museums be left alone to become, as it were, museums of themselves, or should they evolve and become real players in the information business? In the best line of the book, Thomson says "In the future museums will no longer be defined by their collections, but collections defined by their museums". To survive, the great museums must adopt an entrepreneurial attitude to their collections, to be continuously alert about the shifting location of the frontier between scholarship and entertainment.

In the parallel universe of big stores, a similarly dynamic policy has made Selfridge's into a huge success. It is no longer a clumsy and dull monolithic business with a single brand, but a fast-evolving souk of independent concessions under the precise editorship of its boss, Vittorio Radice.

What the chances of this happening with museums are, I cannot say, although I am not fully confident. When I was (somewhat desultorily) interviewed by a weary headhunter looking for a new director for the V&A, I said this great institution could, in a delirium of re-invention, turn itself into a brand, exploit all its intellectual property and do a spot of critical stock-taking. I also pointed to the truism that the responsibility of handling the baggage of the past tends, on occasions, to turn otherwise sensible people into sclerotic old farts when they become museums trustees. And, as you can see, I did not get the job.

I think Keith Thomson would have done. If, as Lampedusa knew, you want things to stay the same, they are going to have to change. What Thomson says is that museums must. Fifty years ago André Malraux spoke wistfully about a future "museum without walls", not knowing how completely computers would bring about that revolution.

And yet, and yet. In a world of double-click to access all the treasures on earth, a special magic resides in real access to real things. That is one explanation of the success of Tate Modern.

There's a delicious and sacred mystery in being close to powerful originals, whether a V-1 Vergeltungswaffe, one of Elton John's coruscating bootees, or a diptych by Simone Martini. The more we get on-line, the more we will want to get in-line for museums.

Keith Thomson has started a fascinating debate that will enlarge when Julian Spalding's more ambitious The Poetic Museum is published in April. In the meantime, we have to wait for museums to be understood forwards.