A Fierce Look at Fidelity : Ann Beattie weaves a rich fabric of truth in an evolving career : ANOTHER YOU, <i> by Ann Beattie (Alfred A. Knopf: $24; 323 pp.)</i>

It’s a difficult trick to bring off, to make your reputation in American literary circles as a writer of short stories only. Raymond Carver did it. As did Flannery O’Connor before him. Ann Beattie has made that image in the American eye. The flurry of stories she published in the New Yorker and elsewhere in the first decade and more of her solid career established her first and foremost as one of her generation’s finest short story writers.

But of her 10 works of fiction, three are novels, and this latest book, “Another You,” is a novel of some distinction, with enough power in the creation of character and such idiosyncratic evolution of the story that it should make us all have to reassess our views of Beattie as an artist. Is she or isn’t she the same kind of writer we thought she was 10 years ago? The answer is that she’s evolving constantly in her work, and we should be grateful for that.

“Another You” certainly dramatizes with great success the way in which anyone--you, me, or the writer herself--evolves over time, from childhood through adulthood. It’s a novel that faces squarely the nature of human character such as we know it, as any of us know ourselves or others, in all of its rational aspects, and in its deep mysteries as well. Marshall Lockard, the main character, is a tenured professor of English with a love of poetry and a terribly confused soul. He’s got a cheating wife who sells houses and a stepmother who’s dying in a nearby nursing home. He’s also got a colleague who seems to have been taking advantage of one of the female undergraduates. As the story kicks in, it appears as though we’re in the midst of an academic novel--a novel of university manners--that’s going to focus on the mores and morals of the contemporary campus.

In other words, it doesn’t appear as though we’re going to visit the real world in this book, just the cloistered world of the teacher and student. There’s certainly plenty of material in the opening chapters to make us think so. Lockard flirting with--even holding hands with and eventually kissing--one of his literature students. Lockard listening sympathetically, horrified to learn that one of his fellow English professors apparently seduced and tortured a girl from the college. Also a meeting over sherry with the president of the school and a big donor in which they trade lines from their favorite modern poets. And some apt slashes of the saber at careerist academics who don’t care for literature, only for literary theory. “No one read books and got excited about them anymore,” Lockard muses. “They argued that transparent plots were murkily opaque and incomprehensible, they projected political interpretations onto literature, then decried offensive political implications. . . .”

The novel veers, though, soon enough from this track. Or dives deep, we might say, into another level, into a past that we find dangled before us in a tantalizing series of letters that appear at the end of nearly every early chapter, letters that seem at first mysterious and eventually become clear as evidence in the novelist’s quest for the truth of Lockard’s personality. And the plot swerves from ironic scaldings of academic life to a fierce examination of marriage, fidelity, honesty and truth of soul. For many long chapters, constructed of paragraphs thick with Lockard’s mental meanderings and flavored with the foolishness and destructive behavior of adults and students alike, we follow the erratic but authentic pathways of recoverable experience. Sometimes we discover along with Lockard that what we assumed to be true is patently false. Sometimes we flounder around with him in the depths of unknowing, flailing our arms in hopes of grasping something to hold on to.

Suddenly the season changes. A story that opened in the cold of winter moves into spring. The novel that began in academia takes us out of the New England college town where it began and carries us south toward the Florida Keys, and the hippie-go-lucky household of Lockard’s brother Gordon. Their stepmother has died; this event has answered some questions about their childhood, and raised many others about their present life. Lockard, the man of thought, meets up with Gordon, the man of action, beneath a shrub called the “flamboyant tree.”

But the novel is anything but flamboyant. As I’ve tried to suggest, it is by turns dour, ironic, thickly composed, with its complexities becoming more and more apparent as the plot evolves, and thus taking on a recognizable, if not always pleasant, similarity to life itself. “Following the complexities of books,” Beattie tells us about Lockard, “had ultimately made him naive about what was happening around him: everyone’s complicated lives; their difficult-to-articulate desires. . . .”

The irony here is that Beattie’s complexities make us more alert to the layered complexities of our own lives, and the lives of others. That’s the main business of the novelist. Short stories concentrate, focus the meaning of things. The novelist lets the world of truth flood over the banks.