Why art went modern: a critical interpretation; The Shock of the New: The Hundred-Year History of Modern Art, by Robert Hughes. New York: Alfred A. Knopf. $29.95

All an art critic has to do to unleash the passions of his fellow citizens is to write a book attempting to define the dynamics of 20th-century modernism. And that is true even if it is made abundantly clear in its introduction that the book represents a strictly personal point of view, that the exclusion of certain famous names results not from ignorance but from technical limitations, and that the intent of the book was not so much detailed and precise categorizations as a large overview of the subject.

Even with such disclaimers, however, the author's critical peers will scrutinize the book with more than usual care. And with justification. After all, being extremely personal in one's views, excluding truly major figures for "technical" reasons, and assuming a highly generalized posture toward the art of the period are in themselves clear expressions of a definite point of view, and, as such, need to be examined as much as the book itself.

We don't, after all, have to accept a book just because the author informs us that its limitations were calculated.

Such is the problem confronting anyone attempting a fair criticism of "The Shock of the New," the book by Time magazine art critic Robert Hughes, based on his eight-part BBC- TV series on modern art currently being shown on PBS.

Two important questions kept nagging at me while reading this book and watching a screening of the TV series: Is it possible to give even a reasonably true account of modernism's history and meaning without discussing such figures as Henry Moore, Georges Rouault, Alexander Calder, or David Smith -- and without doing more with Frank Lloyd Wright than pointing at him and declaring him to have been a great architect? And what sort of perception of modernism would the general reader of viewer receive from this book, or the TV series, or both, if it were his first real introduction to modern art?

The conclusion I came to was that it ism possible to give a reasonably true account of modernism without discussing these figures, as long as we are told why they are excluded, and the ideas they represent are covered elsewhere. I concluded, too, that while a viewer would probably receive an inadequate -- even a somewhat distorted -- picture of modernism if the TV series were his only source of information, such a distortion would not result from a reading of this book.

What the reader gets from it is a fast-moving and fascinating account of what possessed certain individuals toward the end of the 19th century to strike out in different perceptual and conceptual directions than anyone ever had before -- and how various aspects of these modernist attitudes and ideas were then picked up throughout the first half of this century, were expanded upon or twisted, modified or fragmented, until, toward the end of the 1960s and the beginning of the '70s, they all began to dim, to flicker, and to go out.

In short, it's very much a story with a beginning, a middle, and an end. We begin with the completion of the Eiffel Tower in Paris in 1889, and end in the Nevada desert with Michael Heizer's earthwork, "Complex One," and in the wilds of New Mexico with Walter De Maria's mile-long plain of stainless steel poles, "Lightning Field" -- both as far from Paris, our urban society, and our current art-for-museums attitude as one can get in this country.

And in between there's almost as much drama and excitement as exists in a fast-paced novel. There are the main characters -- Cezanne, Monet, Picasso, Matisse, Braque, Delaunay, Duchamp, Tatlin, Le Corbusier, Gropius, Mondrian, etc., -- plenty of secondary characters, and even a few villains.

"The Shock of the New" is extremely well written, and has just enough color illustrations to keep us visually abreast of the text. I enjoyed reading it, and put it down with a real appreciation of Hughes's overall grasp of the subject -- and of how he had managed to make it all come together so well and end so neatly.

That doesn't mean that I didn't find some of his conclusions a bit toom neat and pat. Nor that I agree with all of them. It just means that his handling of the how and why of modernism remains true to its subject throughout, and that the general reader's understanding of modern art should be enhanced rather than diminished by his approach -- highly personal and dramatic as it may be.