Visual art: Figures that don't add up

THERE'S A man who sculpts otters. I'm not sure why, but my home address is on his mailing list and every so often a postcard arrives, showing a photo of Sleeping Otter Cub or Playful Otter or Diving Otter, fashioned in highly polished bronze or soapstone. I admit, over the years, I've got kind of fond of these sleek and streamlined little figures, impossibly cute though they clearly are. But as for reviewing the work of Laurence Broderick (for that's the sculptor's name) - it would be quite unthinkable.

Why? Well, if it isn't evident, it may be hard to explain. It's not exactly a critical judgement - it's more basic than that. It would come down to saying: this otter sculpture is just not proper art; it's beneath consideration; it's tack; it's kitsch; or something like that. But how precisely one would define or justify those so handy words of dismissal I'm not sure. Still, note that we have the mirror image of a perhaps more familiar argument. People who like otter sculpture probably think that a pickled sheep isn't proper art.

I don't want to have an argument, though. I only want to point out something, which is obvious, but rather baffling, namely that taking a neutral, anthropological overview, there is an enormous diversity of self-declared art practices in today's world. The standard distinction between traditional and avant- garde doesn't begin to cover the ground. That's only to consider the up- market goods, and there are vistas here, numerous sets and sub-sets and overlaps, all the stuff that fills small galleries and local town-hall group-shows, the mural painters, the people who do street sculptures.... There is no point saying it isn't art, but it would be a massive and fascinating anthropological job to get it all properly classified.

What saves confusion here is that, exhibition-wise, a fairly strict apartheid is observed. Radically different genres don't normally get shown together. But there are exceptions to this rule - strange, general jostles. There's the Royal Academy Summer Exhibition, of course, which has recently taken to including upfront contemporary art. There's the bizarre Glasgow Gallery of Modern Art. There's the annual London Art Fair in Islington. Critics (me too) tend to find these get-togethers annoying or ridiculous, but I'm not sure our reasons are so strong. Aren't we just making a fuss about untidiness?

One such hotch-potch can be seen currently at the Flowers East gallery. Its title is British Figurative Art - Part Two: Sculpture. It's an extraordinary spectacle. Now, a year ago, as you may have guessed, the gallery hosted a corresponding survey called British Figurative Art -Part One: Painting. But that was a rather different affair, because figurative painting is a more or less familiar category; at least you know who the main suspects will be, and they'll be artists at the traditional end of things. But figurative sculpture? You don't immediately know what to expect, or even who the obvious front-runners might be. Who is the sculptural equivalent of Lucien Freud? No name comes to mind. Curious.

And then, equally curious, if you think about the non-traditional end of things, are the current scene-stealers of British art where quite a few names occur under the heading figurative sculpture: Antony Gormley, obviously; and another caster of his own body, Marc Quinn; and that up- and-coming model-maker, Ron Mueck; and naturally, the Chapman Brothers. And then if you were to include sculptors who made work more generally "about the body" - and I don't see how they could really be left out - you could bring in some women artists, such as Mona Hatoum and Cathy de Monchaux. And remember that Rachel Whiteread once cast the inside of a hot water bottle and called it Torso (one of her most beautiful works). And if "figurative" covers the animal kingdom, should Damien Hirst even be excluded?

That is an imaginary exhibition. I think it would be worth seeing. But it's nothing like what can be seen at Flowers East, and only one of the above mentioned (in a way, though, the most surprising) is represented. What the category "figurative sculpture" produces here is a flagrant miscellany. There's no incitement to consider the state of this art generally. There's nothing approaching unity. You have 40-odd artists represented by 4O-odd works of every sort, and though all the artists are living, of almost every period: from the conventional portrait to spiky "geometry of fear" anatomies; from the fun novelty piece to the maquette for a public monument. There are works which could fairly be called paintings. There are works which, if the distinction means anything, have to be called abstract. There are representations of animals, though none of the otter.

I can't honestly say that I liked more than three or four things in the show, and one of them was not the work by Anthony Caro, though it was certainly a surprise too. It is a portrait, Bust of Clement Greenberg, dated 1988, and done in a claggy, Epstein manner. The surprise is solely in what it is, who by and who of: Caro, since the early 60's the leading figure of British abstract sculpture; Greenberg, the leading American critic-advocate of post-war abstraction generally. In other ways, it's not at all interesting, the kind of thing that lurks justly ignored in many institutions, and though you might suppose it was a kind of jeu d'esprit, that's not how it feels.

Otherwise, to say that many of the pieces were desperately foolish or saddening, terrible tweenesses and terrible jokes, and to wonder what could possibly have inspired the selection, would be to miss the interesting point, which is that, when the normal distinctions come down, you really don't know where you are. For instance, the only bit of bona fide Young British Art included is a severed head with a penis-nose by Jake and Dinos Chapman. Now when you see this in its usual context, in a show of the Chapmans' work, or of their peers', it carries at least a certain attitude: it's cool and real mean.

But see it here, alongside a work like Eleanor Crook's wax effigy of a man with his skin suddenly falling off and his guts - lovingly crafted - spilling out in front of him, which is yucky but actually a pretty genial bad taste gag, then the Chapmans' piece too becomes less sure of its tone. It looks more like genial gross-out too. Or the effect can go the other way: couldn't the apparently trifling, with a different setting, and with the appropriate commentary, become serious? And looking at Laura Ford's Bang Bang, I don't know which way it goes. It's a life-size plaster model of a little girl in a party dress holding a cocked luger, and placed hiding behind a corner, as if stock-still but ready to spring out and shoot. Is it rather fun? Does it raise troubling questions about childhood innocence? Without seeing it in a more singleminded exhibition, you can't tell.

This is a game you can play with perhaps half the show's exhibits. Imagine them as nice. Imagine them as disturbing. And, of course, it is a dangerous game. Breaking down art barriers has long been an avant-garde nostrum, but to see it done with practically no discrimination at all is truly disturbing. It is to see your own culture with something like the view from Mars. I giggled quite a lot going through this show, and I think it was mostly laughter of the nervous kind.

Until 20 September (0181 985 3333)