''This season's hottest group show,'' according to Now, the Toronto entertainment weekly, is a collection of 68 works called Art vs the GST, arrayed at a newish downtown gallery. From the looks of things, I'd say the GST won.

The exhibit was about as dire a display of agitprop as you'd expect. But there is nothing Now likes better than art with a Cause, and there is no cause Canadian artists warm to more than themselves.

The cultural community has convinced itself with very little effort that the goods and services tax is especially unfair to the arts. One's first reaction to gallery owner Don Lake's show is less sympathy than a low whistle of envy. It isn't every industry that can whip together a high-profile media event in support of a tax break and have it reviewed on the arts pages. But then, says Lake, ''art is in and of itself opposed to the tax.''

That, certainly, is what the cultural set would like you to believe. At bottom, the case for excusing the arts from the GST rests on the idea that any tax on art is morally or aesthetically wrong, like taxing love, or laughter, or life itself. A work of art, proponents declare, should not be treated like a widget. The Don't Tax Reading Coalition, a front for publishers and bookstores, makes it a human rights issue, calling the GST a ''blow to democracy.''

The coalition can relax. The GST does not apply to reading. It applies to books. These may be read countless times without additional levies. More to the point, I'll believe art should not be treated like widgets for tax purposes the day that artists refuse payment for their work. Artists aren't averse to soiling their hands in commerce when they're on the receiving end. Why should it be any different the other way around?

The GST, if anything, goes easier on the arts. Canada Council grants, private donations, even corporate sponsorship remain for the most part tax-free. If it's the paperwork they're concerned about, that's covered, too. Most artists make less than $30,000 a year. That means they can opt out, if they wish, under the small traders exemption. The catch is they don't get the credit for the tax paid on their supplies. But who wants to keep track of all those receipts, anyway? They're artists, damn it.

Fine, say cultural groups, but what about those who can't avoid the tax? The arts are acutely price-sensitive, far more so than most purchases. The GST, says one art dealer, ''will destroy the entire art industry in Canada.'' Booksellers restrict themselves to warning the extra 7% on top of prices will cause a drop of 10%, 20% or even 25% in sales. Demand for books is apparently perched on a knife edge: Raise prices from $27.95 to $29.90, and a quarter of the market vanishes.

Given that book sales have been growing at 12% a year, it's difficult to believe consumers are all that finicky. But suppose they're right. Suppose 7% is all that separates booksellers and arts groups from financial ruin. So don't raise prices 7%. Anyone whose product is that preposterously price-sensitive is better off eating some of the tax. You lose some revenue - that's the point of a tax - but you keep volume up.

Publishers usually forget to mention, moreover, that their printing costs will go down, now that they don't have to pay the old manufacturers' sales tax. In fact, any manufactured input the cultural industries buy, or that their suppliers buy, probably carries some MST, which feeds through into their costs. The GST input credit means that won't happen any more. So some of the tax can be absorbed without cutting into margins.

Granted, the tax is more of a shock to those previously outside the federal tax orbit. But that only says that they were unfairly favored by the old system. It is not, after all, the poor who typically purchase a $500,000 Jean-Paul Riopelle at auction. But the revenue forgone there must be made up elsewhere, in higher taxes on clothing, and furniture, and everything else.

If we must involve the state in support of the arts, better to do so by an explicit subsidy than by fiddling with the tax system. Favoring the arts via tax breaks and other such indirect subsidies inevitably winds up enriching a great many others than its intended beneficiaries. Behind every corner bookstore or struggling magazine lies a Coles or Maclean-Hunter.

So either we give anyone who calls himself an artist the same break - my garage mechanic is an artist at what he does - or we are forced to decide: Who's an artist? If that's the question, I'd rather have the Canada Council making the call than Revenue Canada.