Slaughter in Sri Lanka : ONLY MAN IS VILE: The Tragedy of Sri Lanka, <i> By William McGowan (Farrar, Straus & Giroux: $25; 398 pp.)</i>

The Kandyan jungle seemed so at peace just after dawn on that October morning in 1989. In the twisted thicket of palms, bamboo and bougainvillea that blanketed the hotel, a handful of iridescent parrots screeched cheery greetings to the first rays of sun as they splintered into a forest of prisms through the morning dew.

A narrow ribbon of road cut through this ancient heart of Buddhism, deep inside a paradisiacal island so spectacular in its beauty it was once nicknamed Serendip. To the right, just five miles away from the hotel entrance, lay one of Buddhism’s holiest shrines of pilgrimage, the Temple of the Sacred Relic, with its gold cask containing the wisdom tooth of Lord Buddha.

But we turned left that morning, and we hadn’t driven even a mile when we saw our first body--a headless corpse, hands bound behind its back, blocking the road like a fallen tree. A few hundred yards farther, there were three more, then two more, then four more, all with their heads neatly severed at the shoulders.

The jungle road turned up then, into a rich, verdant hillside, and as we approached a bridge over a cascading waterfall, we found the severed heads. There were a dozen or so in all, each carefully placed at 10-foot intervals on the bridge culvert, like horrible mileposts to the civil war that has become Sri Lanka’s living nightmare.

That night, in his modest home near the Temple of the Sacred Relic in downtown Kandy, one of the island’s parliamentarians spoke with quiet frustration of the trauma that this awful era has caused his island paradise and its 14 million people--”We wake up in the morning, and we know tomorrow will be worse than today”--and he tried to square the living death with the religion that had taught them from birth the sacredness of all life.

“We’re not to kill even an animal or an ant,” Shelton Ranaraja said that evening, his body shaken and broken from the horrors that abounded in the peaceful jungle around him. “I don’t understand why this is happening. I cannot explain it.”

It was into this kaleidoscopic hall of horrors that a young American academic-turned-free-lance-journalist brought his abiding curiosity, hope and desire to understand and explain one of the world’s most confounding and remote civil wars. The enduring ethnic conflict grew from an era of Machievellian British rule in which the island’s colonial masters vested the minority Tamils with jobs and power to avoid rebellion from the majority Sinhalese, only to hand that power to the virulently frustrated Sinhalese at independence in 1948.

William McGowan had seen brief glimpses of the conflict in the fall of 1986, when he came to the remote Indian Ocean island formerly known as Ceylon to serve as an adjunct professor at the School of International Training. His self-appointed task when he returned a year later was far more daunting: to live for a year on an island that journalists visit only briefly, a land already five years and 8,000 dead into the brutal conflicts that have so defied comprehension. His goal was to understand the cultural, historic and religious roots of Sri Lanka’s lethal labyrinth.

The result, “Only Man is Vile,” is billed on the book jacket as an “explosive” and “gripping political travelogue” that not only explains this evil coexistence of corpses and lotus flowers to an uninitiated Western reader, but contributes to “the literature of cultural identity, East and West.” It was an excursion into the realm of anthropological and cultural realism that clearly left McGowan as deeply disturbed and tormented as any who have ventured into this paradise lost. McGowan writes often of his fears, his nightmares and, ultimately, toward the end, the deepest dread that accompanied the end of his search:

“The fear I had repressed on earlier excursions into the war zones was now uncontainable,” he explains in opening his final chapter with something of an apology for looking no further. “Memories of burned bodies, land-mine victims and morgue scenes sprang forth in me.”

McGowan unfortunately confirms time and again the reader’s own fear: that they will follow the author on his journey into horror, but he will abandon them there, unable to get to the roots of a war that is as complex as it is confounding. “Even though I had learned much over the two years I was there,” McGowan explains in the preface, “I still had nagging doubts that I had missed something, some avenue of hope.”

McGowan gets close enough to describe the concussion of incoming mortar fire from the Indian troops who met their own Vietnam trying to put down the Tamil insurrection that they had helped create, a guerrilla war that continues even today. But through frequent and admirable self-effacement, he continually confesses his failure to break ranks with the visiting journalists. The foreign correspondents appear to intrigue him almost as much as the island itself; although they remain his constant traveling companions on his search for truth, they seem to keep the author himself on the level of the superficial.

“When the ground started rumbling with the concussive force of approaching artillery and mortar fire, we turned back. We spent the rest of the day in a safe house,” he explains during one visit to the embattled northern Jaffna region that is the heart of the Tamil rebellion.

The author stresses painfully often the island’s “culture of avoidance” and “culture of denial,” deep-seated shields that keep all probing eyes--including the author’s--continually in the dark. In the capital, Colombo, where McGowan made his home, “the . . . elite as a whole was skilled at avoidance . . . as if the entire community was living the old Ceylonese adage that ‘a well-told lie is worth a thousand facts.’ ”

As McGowan acknowledges time and again, he never seems to penetrate that shield, keeping the reader on the outside along with him. In his attempt to describe the island’s famed and ancient annual Perahera festival, which begins in the chamber of the Sacred Relic Temple containing Buddha’s tooth, he writes: “There was a lot of confusion in the chamber, no clear sense of what was going on or who was doing what.”

In a lengthy chapter that searches for the roots of Sri Lanka’s resistance to international economic development, McGowan focuses almost entirely on a frustrated American trying to build a prawn farm just north of Colombo. He quotes the American agriculturist to explain, “You learn pretty quick around here that nothing is as simple as it should be.” McGowan then ventures into the nearby village to explore the deeper cultural and social-caste causes that appear to inhibit rural development, but observes, “Many of the villagers wouldn’t talk to me, because, as one of them explained, ‘I was not from there.’ ”

Nonetheless, McGowan asserts that his visit to the prawn farm had given “a pretty good sense of ground-level development problems,” but then he observes, “I was eager to talk to international development officials in Colombo to get their idea of the role that social and cultural factors played in frustrating their expensive efforts. But the people I spoke to were either unable or unwilling to talk about such problems.”

What emerges from McGowan’s painstaking and bold effort to explore Sri Lanka’s contradictions is merely a reaffirmation of the confusion. He uses the characters that abound as well as confound in this strange land merely as brief, stiff vignettes rather than human vehicles to penetrate that culture of denial. He presents the foreign correspondents who traipse through the jungle along with him as cynical “fire men” who specialize in the superficial “boom-boom” of war, and yet he makes clear his own personal fascination with those same journalists, who oddly emerge as the book’s most intriguing and best-developed characters.

Almost lost in McGowan’s pages of hand-wringing doubt and sometimes angry frustration are some nuggets of brilliance. A chapter entitled “Christmas in Batti” is a travelogue of McGowan’s holiday visit to the Catholic bishop in the war-torn east-coast town of Batticaloa. The trip becomes a vivid, escalating cycle of violence, beginning with a terrifying bombardment of the rectory by India’s “peacekeeping” force. Here the story takes us as close to the roots of the island’s despair as any account ever written: “If they gave me an injection to die, I would take it,” a retired Tamil railroad clerk tells McGowan. The author continues: “The train we were on finally lurched forward after soldiers discovered no bombs aboard.” Then, returning to the railway clerk’s voice: “It is no longer good to live here. Hitler was a good man. At least he killed the Jews all at once. Here, they are doing it slowly.”

McGowan would have needed many more such characters to show him the inner workings of a national soul that could leave so much flesh so casually discarded in the verdant jungles of Serendip.

“I left Sri Lanka burned out, physically and emotionally,” the author unabashedly explains. “During all the time I spent thinking about and writing this book, I resisted the full implications of what I had seen and come to feel.”

“The full implications” are exactly what the reader misses, but what are in Sri Lanka’s situation, perhaps, impossible to deliver.