SUBTRACTION By Mary Robison Knopf. 216 pp. $19.95

PAIGE DEVEAUX is a Harvard professor and poet whose current work-in-progress is a long poem titled "Enantiotropy" (don't ask what it means -- it doesn't matter). Her husband, Raf, is nothing but trouble: a faithless alcoholic who runs away from home whenever things get rough. When Paige leaves her cozy Cambridge house to search for Raf in his latest hideout, a seedy section of Houston, passions explode in the steamy July heat like a battered pinata.

Or so Mary Robison would like us to believe. These characters, the stars of her second novel, Subtraction, are more remarkable for their peculiar combination of the highbrow and the lowdown than for their passion. Raf, whose latest farewell note to Paige was a quotation from Nietzsche, is a former Princeton philosophy student who has held jobs as a foundry worker, a lobster fisherman, a Las Vegas bouncer and a construction worker. Paige, who narrates the story, is known to write tercets in times of crisis but has no problem swigging beer and playing cards with the women from a local Houston slum.

Slumming, in fact, seems to be the real subject of this novel. These are characters who, despite their Ivy League credentials, insist on living on the edge. Why else would Robison introduce Pru, a rich girl turned stripper, who claims she dances nude in a nightclub out of "contempt" for mankind, buys only "politically correct beverage products," and delivers sermonettes to anyone who will listen about feminism, the rain forests and government censorship?

To round out this high-toned group, we are given Raymond, an old Princeton friend of Raf's, whom Robison portrays as a Marlboro Man from somewhere in the Southwest, with "blond, metal-bright hair" and the ability to make profound observations in an irresistibly sexy drawl.

It is Raymond who helps Paige track Raf down in a Hispanic dance hall on the outskirts of Houston. But although Paige's apparent willingness to rescue her husband from the sleaziest depths is arresting at first, after a while her devotion begins to strain the reader's credulity.

Though all the other characters in Subtraction are constantly remarking on Raf's attractiveness and charm, Robison fails to make his so-called charisma convincing. Here, for example, is her first description of Raf: "He did look handsome in his way, in his loose black suit, although there was a badge-sized bruise on his left cheekbone below his glass eye, and he seemed far along in his drunk. Just moving back and forth along the bar he stumbled twice."

While this is hardly an enticing portrait, when Robison adds the fact that Raf is the kind of self-hating alcoholic who is fond of making such smart-alecky statements as "It's not an authentic day for me unless I degrade myself in so many ways," it is hard to imagine what Paige and others in the book find so winsome about this creature.

Paige herself, who brags of having "an arts grant bigger than my Harvard salary," is all fancy credentials with barely any depth. She is that late-1980s phenomenon, the Smart Woman Who Makes Foolish Choices, whining to her mother that "Raf's a bad husband. I deserve a good husband. Why do I still want Raf?" To which her mother responds: "He's an awfully good time." But Robison never gives her protagonist enough complexity to expand beyond this kind of superficial dialogue, so that Paige remains not so much a character as a cliche.

Raymond and Pru, for their part, fade in and out of the narrative at random, as do Paige's thinly sketched parents, Dottie and Mario. Since they seem to exist primarily as temporary distractions from the wearisome cat-and-mouse game that Raf is playing with Paige, these peripheral characters are allowed to develop very little life of their own.

Mary Robison is primarily known as a writer of short stories (she has published three collections, titled Days, An Amateur's Guide to the Night, and Believe Them), and perhaps Subtraction -- a curious title, never explained -- would have had more narrative punch in a shorter form. Stretched out to fit the roomier dimensions of a novel, neither the plot nor the characters have enough strength to sustain themselves over nearly 200 pages. In the end, Subtraction does not manage to add up to much at all. Donna Rifkind's reviews have appeared in the Wall Street Journal, the New Criterion, the Times Literary Supplement and other publications.