An Obituary for Modern Art : NOTHING IF NOT CRITICAL; Selected Essays on Art and Artists <i> By Robert Hughes (Alfred A. Knopf: $29.95; 429 pp.)</i>

Robert Hughes seems like a throwback to the 19th Century, to a time when everyone seemed possessed of limitless energy, and when a bad day was when you could only scrape together an etude , a couple of pencil sketches or the odd book review. Year after year, ever since he first came to New York in 1970 from his native Australia by way of London, Hughes’ output has been dependably prodigious.

Not only is he in his second decade as Time magazine’s principal art critic but he also has written “The Fatal Shore,” an exceptional account of the forced transportation of convicts to Australia, and turned out “The Shock of the New,” the BBC’s much admired series on modern art. There also have been definitive catalogue essays on the work of such painters as Lucien Freud and Frank Auerbach, a history of the images of heaven and hell in Western painting, and a book on Australian art.

Even more imposing is the fact that, just past 50, Hughes seems, if anything, to be just now hitting his stride. His essays keep getting better, the result of his now 10-year association with the New York Review of Books, which has provided him with a context in which to write at greater length and on subjects other than art.

Whatever project Hughes decides to take on next, the appearance of 20 years’ worth of his essays in “Nothing If Not Critical” alone is more than enough to secure his reputation. Placed in the sobering integument of a collection, even those Time pieces that seemed a little weightless when they first appeared now adhere, integral parts of a larger argument that Hughes seems to have been making for most of his career. It turns out that beneath the dandyish prose lies a fierce moralist, and that if Hughes’ writing always has appeared to be an improbable combination of Oscar Wilde and Savonarola, then in the end the reformer is by far the more powerful presence.

Although the book contains essays on painters ranging from Holbein to Diebenkorn, and from the German Romantics to the late paintings of Picasso, and can be read pleasurably as art criticism, all the pieces in the collection serve to clarify the question that obsesses Hughes: the situation of modern art, and, through it, the whole idea of modernity itself as it has been understood throughout this century.

To say that Hughes is gloomy about what has gone on and gloomier still about what is in store would be an understatement. Surveying the artistic landscape, he finds little of value, least of all in New York, the city that for so long was thought to be synonymous with the avant-garde in all the arts.

Hughes’ courage in taking the positions he has should not be underestimated. We all have a tendency to praise the art of our own time even when, in our hearts anyway, we know it really isn’t very good. This is understandable enough, since to reject the art of one’s own time is not only to distance oneself from one’s contemporaries but also, in effect, to stand at a certain remove from what is, after all, the only time in which one will be alive. It is never comfortable living at the end of a period of great creativity, more uncomfortable still to admit that the glorious moment has passed, and yet that is precisely what Hughes is asking us to do. “It may be,” he writes somberly, “that Picasso’s death in 1973 marked the end of a period in Western art as emphatically as the deaths of Sophocles and Euripides in the same year, 406 BC, marked the end of high tragic drama in Greece.”

Hughes’ critics--and they are legion in the art world--are fond of saying that he is little more than art criticism’s answer to Allan Bloom or Paul Kennedy, a facile theorist of decline whose views mask a crude lack of sympathy with the direction the plastic arts have taken during the past 20 years. Of course, the assumption that what is new is always good is not some iron law of the universe but rather one of the central intellectual presuppositions of the very movement--modernism--whose obituary Hughes has undertaken to write.

That being said, there is no question that all arguments for decline, whether about empires or art forms, bear a certain family resemblance. But what matters is whether they hold up. And given the fact that any objective person would surely agree that the only way to plot a curve between Picasso and Andy Warhol is straight down, one would think that Hughes had at the very least earned the right to a hearing.

At the core of his argument is money. Despite certain surface similarities, there is, Hughes argues, simply no historical precedent for the way in which the value of works of art (and, he would add, the reputation of artists) has been inflated since the late 1960s. It has more to do with Tulip Mania or the South Sea Bubble than with connoisseurship, and everything to do with capital gains.

As Hughes puts it, “the whole relationship between art and money shifted so greatly after World War II that our way of perceiving art in its social relations (what we expect from it, how we approach it, what we think it is good for, how we use it) has been deeply, if not always consciously changed. What we are seeing, in the last years of the 20th Century, is a kind of environmental breakdown in the art world.”

In effect, Hughes is really saying that the story of the avant-garde is over. “The market story of post-modernism so far,” he observes tartly, “is the story of Van Gogh’s ear, without Van Gogh himself.” There is, he thinks, little to be hoped for from most American artists, whom he views as more personalities than painters.

Certainly there is nothing more that can be expected from New York, whose collapse as the world’s single art center Hughes anatomizes with a kind of bitter rue in the opening essay of the collection, “The Decline of the City of Mahagonny.” (Lest California’s more primitive boosters get the wrong idea, Hughes, though he has some kind things to say about James Turrhell, and some respectful words for Richard Diebenkorn, is scarcely predicting a shift west.) Painting is an invalid, Hughes argues, and he goes on to speculate that “perhaps in the nineties, the necessary reconstruction work on the strip-mined sites of late modernism will be done in Britain and France. . . . And even there, one should not expect too much, or expect it too soon.”

This elegiac tone is not what most readers probably expect from a writer best known for the verve and wit of his prose. And, indeed, Hughes’ spirited demolitions of Warhol, Schnabel, Basquiat and the other Soho frauds have been included in the collection and are, by themselves, worth the price of the book. But what will last (as opposed to what is simply vastly enjoyable) is Hughes’ great and necessary Jeremiad against the con game that the avant-garde in its dotage has become.

“Nothing If Not Critical” will certainly not do the price of art any good (the real service most collectors have now come to expect from most art critics), but it is as close as we are going to get to reading posterity’s judgment on our own times.