Art and science may both be ways of understanding the world, but that does not mean they are interchangeable enterprises. In fact, it's likely that a Richard Dawkins of the arts is an impossibility

Brian Eno asked an impertinent question earlier this week. Before handing the Turner Prize over to Damien Hirst he put this to the assembled gathering: "Why have the sciences yielded great explainers like Richard Dawkins and Stephen Jay Gould, while the arts routinely produce some of the loosest thinking and worst writing known to history?" An impertinent question, whatever its larger pertinence, because the gathering in front of him contained quite a few of the people responsible for that writing. He was rewarded for his frankness with a slightly uneasy murmur, the almost imperceptible sound of fur being rubbed the wrong way.

It is easy to sympathise with the second half of his statement. Anyone who has ever tried to advance through the no man's land of the average catalogue essay will know what he is talking about - prose like barbed wire, leaving comprehension exhausted and dangling. But the more you think about his proposed solution, the clearer it becomes that it simply wouldn't work. Art and science may both be ways of understanding the world in which we find ourselves, but that does not mean they are interchangeable enterprises. In fact, it's likely that a Richard Dawkins of the arts is an impossibility.

One obvious thought offers itself at once: that is, that art and science have a very different attitude to complexity. The sales of popular science books, Eno argued, "indicate a surprising public appetite for complex issues". But while science certainly has uses for complexity, the enterprise is essentially dedicated to its diminution. The Grand Unified Theory, the holy grail of modern physics, is an attempt to merge many explanations into a single one. And, as the popularisers of science repeatedly point out, "beauty" is a term roughly equivalent to simplicity or clarity.

In the arts, though, complexity isn't a veil we wish to strip away from the world. It isn't a register of our failure to grasp some higher order of truth. This may not apply to all times, but it certainly applies to this century, in which art has been dedicated to ambiguity, the absence of categorical statement, the desire to excite a fruitful confusion in those who look at it. There can, then, be no simple equivalent of the scientific go-between, translating the arcane knowledge of professionals into something comprehensible to the ordinary joe. There simply isn't a right answer to the mystery of a Titian.

The blurb on the cover of a paperback edition of Richard Dawkins's The Selfish Gene helps to illuminate the difference. It reads, "The sort of popular science writing that makes the reader feel like a genius". Not bad for a blurb and spot on, as it happens, about one large appeal of popular science - its implicit promise to expand your sense of control in the world, to make you rich in facts.

But facts, even theories about facts, work in a different way in art because they are ultimately answerable to our own emotional proof. Barely anyone reading a popular work about particle physics would be able to put the book down and set off, full of enthusiasm, for their local particle accelerator. But virtually everyone has some access to the raw data of art.

In other words, if works of art are experiments in human perception, they are experiments which finally have to be conducted by each one of us individually. The results cannot be taken on trust because they will, by definition, vary from occasion to occasion. What's more, there is no obvious test of the validity of our findings except for a kind of democracy of the plausible. Someone might conceivably take the view that Damien Hirst's Mother and Child Divided, his controversial sandwich of bisected cow and random art-lover, is a profoundly moving meditation on the partition of India. It would be difficult, even for the artist, to argue that this was categorically wrong but such a person would be likely to persuade far fewer people than a more illuminating interpretation.

There is room for good writing about art here - for an infectious intelligence to go to work on the experience of looking at good and bad art - but it is unlikely to offer the same pleasures as the excellent writers Eno mentioned. Science, rightly or wrongly, offers us authority and a sort of certainty. (Stephen Jay Gould's essays are actually classic sermons in their form, beginning with a text - some natural curiosity - and moving outwards to a larger principle.) To put it simply, the best writing on science points towards the right answers; the best writing on art points us towards the right questions.