Design: Go on, I know you want to

`I think of women's shoes as a matter of aesthetics.' The novelist Geoff Nicholson explains his obsession

`See a shoe and pick it up, and all day long you'll have good luck." This is a caption that accompanies one of Andy Warhol's shoe drawings, in his book A la Recherche du Shoe Perdue.

You want to say, "No, Andy. All day long you won't have good luck, you'll just have a shoe." But what's the point trying to argue with genius?

Warhol's shoe drawings are fey yet voluptuous, a wobbly blend of the ingenuous and the disingenuous, the naive and the faux naif. They were mostly done as commercial illustrations for magazines and shoe companies, but Warhol's interest in shoes was not simply or narrowly commercial.

Pad along to the Barbican, to the exhibition "The Warhol Look: Glamour Style Fashion" and you'll be able to gaze in awe at Andy's very own "Beatle boots", enclosed in a perspex case that seems to be trying to make them look significant and "museum-quality", but only succeeds in making them look morbidly fetishistic.

You'll also see a bulging box of extremely elegant, and scarcely worn, women's shoes, collected by Warhol with the same acquisitive passion he applied to Hollywood star portraits and cookie jars. But a desire to possess shoes comes from quite a different psychic area than the desire to possess cookie jars in the shape of Donald Duck.

In his biography of Warhol, Victor Bockris says Andy was a "classic foot fetishist" but this begs a great many questions. Warhol may have drawn and collected women's shoes, but his personal sexual preferences lay elsewhere. However, his drawings of men's feet, which were his real passion, show much the same delicacy as his drawings of women's shoes. It's unusual to find someone who's equally at home with the feet and shoes of both sexes.

Men and women just don't feel the same about these things. Very few men in the world have ever had a girlfriend who has asked them to keep their shoes on during sex. There are very few women who haven't been asked to keep theirs on by a man. Admittedly there's some unisex footwear; the Wellington, the trainer, the flip flop; but these are only unisex by virtue of having become sexless. Perhaps there are one or two people who are whipped to arousal by the sight of a green welly, but if so it's just too weird to contemplate.

There are certain shared fetishistic forms, the tight, highly polished knee boot for instance, which can be worn by both men and women, but the woman looks like a hot babe in hers, the man looks like a Nazi in his. That too may be hot for some, but it's not an equivalent kind of heat.

You will certainly find some women who say, "I've got a bit of a shoe fetish". But what they mean is that they own hundreds of pairs of shoes. This is not what a man means when he says, "I've got a bit of a shoe fetish".

Some women buy shoes because they want to appear sexually attractive, but all too often it's a form of commodity (not to say shopping) fetishism rather than sexual fetishism. And it's a rule of thumb, if not quite a law of nature, that at least half the shoes in these women's collections will be clumpy or camp or simply frivolous. Frivolity is not one of the things the male fetishist seeks in the object of his desire.

But why the desire? Freud will tell you it's a matter of phallic substitution; a view I shan't argue with except to point out that a shoe seems a less than perfect substitute for a phallus. I prefer to think it's more a matter of design and aesthetics.

The sort of line and curve, the spatial and sculptural qualities that make a shoe look sexy, also make buildings or cars or electric guitars look sexy. Shoes are involved in the process of reshaping and customising the foot, a kind of streamlining. Whereas feet are splayed, shoes are pointed. Where feet are flat, the shoe provides an arch. Where feet are simply flesh-coloured, shoes provide the excitement of diverse, exotic fabrics.

Then there are individual design features that have specific meanings: the high heel which hobbles the woman while making her look high and mighty, the ankle strap with its hint of bondage, the penetrative possibilities of the peep toe.

If some people claim to find all this mysterious and incomprehensible, others have understood the issues since we first raised our feet out of the mud, and fortunately some of these have been shoemakers and shoe designers.

We have to make a distinction here between being turned on by the aesthetics of shoes as opposed to by the name of the manufacturer. But this is meaningless, just a different form of commodity fetishism, fetishising the name rather than the object. No designer or company gets it right every time. Those wonderful strappy, high-heeled sandals with which Ferragamo made his name in the Thirties and Forties find very little echo in the current Ferragamo range. These days Jimmy Choo is far more likely to come up with something wonderful combining classic shape, sensual fabric, and understated eroticism. Emma Hope seems to toy with the erotic possibilities of chaste formality. Aydin Kurdash is performing small miracles at Gina, making backless boots and using elasticated leather.

And then there is Manolo Blahnik. There is always Manolo Blahnik. If you needed someone to make a pair of shoes to save your life he'd be the man. He creates that perfect balance between convention and invention, between the classic and the newfangled. He uses silk shantung, red suede, pink feathers. His shoes are delicate yet fierce.

You wouldn't be naive enough to call these shoes practical, but they're balanced, harmonious, wearable. They're not just limousine or boudoir shoes. And if you don't understand shoe fetishism after you've seen a Blahnik collection you never will. But Blahnik is on record as saying, "I really cannot deal with sex. You see some people just make sex paramount, but I don't think it's important at all. Sex is utter nonsense, it's in your mind, yes. I have an incredible sex life in my mind. But I don't apply it to people. I put everything I think is sexy into my shoes."

I'm never sure if this is the saddest or the most sophisticated thing I've ever heard. But what I think he's saying is that life may not always be all about sex, but that shoes are. This doesn't mean that all shoes are sexy, but it means that they always make a statement about sex. A woman in a pair of penny loafers is making as powerful a statement about sexuality as is a woman in a pair of sequined stripper's shoes from Frederick's of Hollywood. It's just that men feel rather more encouraged by one statement than the other.

A woman friend of mine was going home from work on the bus one day, and had absentmindedly kicked off her high heels and tucked them under her seat. When she came to her stop she felt for the shoes and they'd gone. The man in the seat behind her had reached under, taken them and disappeared. She thought this was outrageous, infuriating, sick, and certainly had the sense that the pervert shouldn't be allowed to get away with it. Barefoot she walked to the police station, not at all sure she'd be treated with respect, but she went anyway, since a matter of principle was at stake here.

To her surprise the police treated her with a great deal of sympathy. They saw how disturbing this sort of thing might be to a sensitive woman, and the plod on the desk assured her that the thief wouldn't have gone far. "They like to use them while they're still warm," he informed her, conjuring up a whole series of mental images that until then she'd been able to suppress.

They didn't catch the guy and actually I think it's just as well. I mean, if he was sharing a cell down at the local nick and one of the other inmates asked him what he was in for, well I suppose he could have said he'd been driven to steal the shoes out of aesthetic motives, or I suppose he could have said he'd heard that picking up a shoe guaranteed a day of good luck, but I think it wouldn't have gone down too well.

He might even have said he was paying homage to Andy Warhol. I'm sure that would have gone down worst of all.

Geoff Nicholson is the author of `Footsucker', a novel about foot and shoe fetishism. His latest novel is `Flesh Guitar' (Gollancz).