BOOK REVIEW / MEMOIR : The Cloudy Syntax of Writer as Politician : A FISH IN THE WATER: A Memoir, <i> by Mario Vargas Llosa</i> ; Translated by Helen Lane; Farrar Straus & Giroux; $25, 532 pages

Mario Vargas Llosa’s wife, Patricia, was angry with him for a whole year. For one of Latin America’s two greatest novelists to throw himself into a bloody campaign to become president of Peru, she argued, was to sacrifice both his art and his family. Surely, he was only in it for the excitement, for the notion of writing a great novel--not on paper, but in real life.

Having argued, though, she turned wholeheartedly to helping him. Perhaps she thought that the more thoroughly he went at it, the more completely he would get over it.

“A Fish in the Water” seems to be part of the still-shocked ordeal of getting over it. Possibly the title of this curious hybrid of campaign journal and childhood memoir is ironic. “Fish Out of the Water” would be truer--if not to what Vargas Llosa means to say, then to what he actually manages to say.

After an early enthusiasm for Marxism and the Castro revolution, Vargas Llosa drifted to the right side of the divide that works to place Latin American authors politically, quite regardless of the character of their art. (By their writing you would have a hard time making a political distinction between Vargas Llosa and Garcia Marquez--across the gulch--or between the “conservative” Jorge Luis Borges and his “leftist” compatriot, Julio Cortazar.)

In 1987, convinced that the capitalist examples of South Korea, Japan and Taiwan offered a better hope for his country’s misery than the distributive, government-directed economies traditional to Latin America’s democratic left, Vargas Llosa wrote a fierce attack on Peru’s president, Alan Garcia. There was a lot of response, and before long the writer found himself the presidential candidate of a middle-class and professional civic movement allied with two established parties.

Running against the government candidate and a Socialist, Vargas Llosa soared in the polls for a while, then declined and was finally humiliated in two rounds of voting. The victor was Alberto Fujimori, an agriculture professor who shot up out of political obscurity at virtually the last minute. Riding on the swell of anti-politician feeling that Vargas Llosa’s group had set going and then fumbled, Fujimori won with an ironically similar program.

Many of those allied with Vargas Llosa--including the business and financial groups whose backing turned his initial popular support into popular distrust--now back Fujimori and the dictatorial powers he has assumed.

Vargas Llosa is a bitter opponent--and the most bitter thing is when ignorant acquaintances congratulate him on the “triumph” of his ideas. In Latin America, after all, such ideas have traditionally been associated with authoritarians and dictators.

Politicians blur distinctions; writers live by them. In the anti-guerrilla fight, for example, Vargas Llosa wanted to arm the peasants--not to serve the army but in part to replace it.

So the half of “A Fish in the Water” that is political memoir is the record of a quixotic endeavor. But Don Quixote was luckier. He tilted at windmills, thinking them giants, and ended up up-ended.

Vargas Llosa, trying to write himself into a politician, thought he could acquire the windmill and turn it into a giant. And he ended up--what with his associates easing a crusade into a thoroughly conventional political operation--juggling cogs, paddles and grease, paying dues to the millers’ consortium and quite covered in flour.

In “Fish,” he is not yet dusted back into writing form. There are useful things to be learned, but these are clouded by a swollen volume of detail: campaign trips, excoriations of a few associates and many enemies, and a structure that goes “and then . . . and then.”

The campaign chapters alternate rather forcedly with others recalling his childhood and growing up. There is a notable portrait of his father, who abandoned Mario’s mother before he was born and returned 11 years later to turn his golden childhood into an eccentrically terrifying one.

There are accounts of military school, university, early attempts at journalism and writing, and his scandalous marriage to the sister of an uncle’s wife (fictionalized in “Aunt Julia and the Scriptwriter”).

Much of the material here is interesting, and there are passages of brilliant evocation. But, as in the campaign journal, the writing seems loose and hasty, as if Vargas Llosa’s artistic heart were not entirely in it. He writes that during the campaign he had to give up serious writing because his “beloved demons” had fled. In “Fish,” they have not quite returned.