BOOK REVIEW : Buoyant Writing and Weighty Themes : SANTIAGO AND THE DRINKING PARTY <i> by Clay Morgan</i> ; Viking; $21; 275 pages

This mystical, semi-autobiographical novel officially begins when the narrator tips a globe on its axis and decides to light out for somewhere near the bottom.

Patagonia, as close to the end of the world as you can get and still use the Roman alphabet, looks good to him. Idaho, where he’s been working in a logging camp after dropping out of college again, looks bad, or at least unpromising.

He’s just narrowly avoided killing his employer by misjudging the speed and angle at which a 150-foot Douglas fir would fall, definite proof that there’s no future for him in the lumber business.

To his friends, “commitment meant marriage or a job, but to me it meant something worse, something like the end.”

Even in the mid-’70s, Daniel Cooper is a late-blooming hippie--directionless, unambitious, emotionally unattached to any person, place or thing in his native country. While his contemporaries are cutting their pony tails and signing up for MBA programs, he’s still lost and starting to feel like the last guest at a party where the hosts are yawning as they clear up the mess. Once he’s in Patagonia, nothing seems quite as urgent as leaving it. Getting there by plane and train was easy and expensive; getting back, by bus, ferry and walking, will be strenuous, cheaper and longer.

After various extraordinary hardships, he winds up in a jungle clearing near the minuscule river village of Puentes Caidos, named for the fallen bridges that isolate it from the rest of the country.

Where Colombia represents the acme of sophistication, you’re a long way from Boise. Puentes Caidos, however, is home to the self-taught philosopher Santiago and his ravishingly beautiful daughter, Angelina. Socrates himself, who provides the significant epigraph, “Do you mind if I ask you a question or two?” had a far less tranquil life than Santiago.

Daniel, of course, falls irrevocably in love with Angelina, but even though she tenderly nurses him through a bout of malaria and offers every possible proof that she returns his feelings, he slips away after his fifth day in paradise and returns to the States, ready to give adulthood a try. That doesn’t work out. By the beginning of the third chapter, 15 years have passed and he’s booked passage back to Puentes Caidos and Angelina.

One sentence describes his decade and a half of American life: “Everybody jogging, which seemed like the symptom of a mental running in place.”

This time he has a destination, but when he arrives at the site, the village has vanished, although he later discovers that it has merely moved up river. The abandoned bus in which Santiago and Angelina had lived is in ruins; their garden an infants’ graveyard.

Despite the grisly nature of these and succeeding symbols, Morgan’s touch is light and the account of his adventures often comedic. The author of “Santiago and the Drinking Party” never allows his weighty themes to sink a naturally buoyant prose. The discourse (or, if you prefer, the Socratic dialogue) on the meaning of life, love, good, evil and other substantial themes remains earthy and succinct, as suits a seminar whose members meet over beer in a jungle cantina.

Resisting any temptation toward elevated language or convoluted expression, Santiago’s “thinkery,” as he calls his symposium, is a true peoples’ academy; the participating philosophers lend a new dimension to the idea of diversity.

Once ensconced again in Puentes Caidos, Daniel participates fully in village life. Still providentially unmarried and exquisite as ever, Angelina has become a successful entrepreneur, exporting rare flora and fauna all over the world.

Unwilling to begin the romance abruptly ended when Daniel left 15 years earlier, she encourages him to be consoled by the aptly named Consuela, who has served all Angelina’s spurned lovers in a similar capacity.

Too arduous to be exactly idyllic, life in Puentes Caidos proves wonderfully rewarding for Daniel until the town is beset by a series of escalating horrors, catastrophes closely resembling biblical plagues.

In addition to flood, frogs, insects and a terrible tropical disease, the village of Puentes Caidos must cope with a French TV crew and a brutal local con man.

Although the analogies are inescapable and the invitation to make these connections amounts to intellectual coercion, “Santiago and the Drinking Party” rises above the obvious to become a cautionary tale that delights while it edifies.