BOOK REVIEW / NONFICTION : Historical Walkabout With Talleyrand : THE RUIN OF KASCH <i> by Roberto Calasso</i> . Belknap Press/Harvard University Press: $24.95, 356 pages

Dante chose Virgil to lead him through Hell; possibly an arbitrary choice and rather hard on the pagan Roman, but it served to give gravitas to the Florentine’s scandalous walkabout.

At first glance, it seems an oddity for Roberto Calasso to choose the chilly diplomatic maneuverer, Talleyrand, as tutelary spirit to his incandescent scrapbook of humanity’s myths and endeavors.

In “The Ruin of Kasch,” Calasso, the epigrammatic Italian writer, makes as if to tie up the history of absolutely everything in an improbable net-bag secured with knots that often come undone and spill the contents, but sometimes bring up quite marvelous catches.

Yet making our way through what is not so much a book as a compendium of asides--on everything from Vedic myth to Freud, Hegel, Marx and Walter Benjamin; to Goethe’s necktie, to a French aristocrat who visited her lover dressed up as a bear, to the contents of the stalls in the Palais-Royale (a chaste monument today but in the 19th Century a bawdy, teeming caravansary)--we realize that Calasso does not take his knots seriously.

Does it matter which fish are caught and which escape?

Either way they glitter, although not so much as in Calasso’s “The Marriage of Cadmus and Harmony,” his dazzling reworking of Greek mythology. Here, in his first and more ambitious book, there is more churn to each glitter.

There is also a thread of a theme, and it makes the choice of Talleyrand as master of Calasso’s revels wittily appropriate.

Widely detested for cynicism and changeability (and widely usable for the same reasons), he dispensed his skills to the French Revolution, the Directory, Napoleon, the Bourbon Restoration and the citizen-king, Louis-Philippe.

He was a master of currents, surfaces and, above all, of limits.

In the 19th Century, when leaders, thinkers and artists thought of themselves as shaping events--they shaped them imperially and finally into World War I, where shaping was taken to its insane extreme--Talleyrand confined his art to conferring “the little finishing touches.”

He used indolence, Mme. de Stael wrote, “to thwart as naturally as possible the activity of others,” and was master, Calasso writes, “of the art of hiding everything on the surface.”

“The Ruin of Kasch,” skipping aimlessly from one glittering and seductive bit of history and legend to another, makes aimlessness its purpose.

Calasso does not establish a conclusion; rather, each of his anecdotes and reflections seems to come to its own dead end, until we realize that all the dead ends are roughly in the same place.

He distrusts purposefulness and progress; he suggests that each linear effort leads to disaster (as with Marx) or absurdity (as with Jeremy Bentham, who took the science of measurement to the point of declaring that the concept of goodness must be quantified in money terms).

He is interested in cultures that go by cycles and limits.

In the allegory that gives the book its name, he tells of a prosperous African kingdom, Kasch, where the king was supreme but where the priests, consulting the stars, would periodically order his execution and replacement by a new king.

One king, however, discovered a magical storyteller whose tales lasted all night and so enchanted the priests that they forgot to look at the stars.

The king lived out his life span and so did his successor, the storyteller. Happiness was unalloyed until the neighboring peoples, jealous of utopia, came in and destroyed it.

Calasso writes of Talleyrand’s last negotiation--with the Vatican--concluded with bluff and artful timing on his deathbed. It produced a document that was a kind of minimal confession and gave him access to the Church’s last sacraments.

There was no time for the Vatican to amend it, and even though it was unacceptable it would have been too awkward to declare it unacceptable. For Talleyrand, even salvation was found in surfaces and was to be obtained, to say the least, in a limited way.

After the notables--including the citizen-king in a scruffy brown coat--paid their respects, the dead Talleyrand lay alone.

His chef entered, according to one account. Followed by his assistants “with their snow-white costumes and long carving-knives, (he walked) with solemn step to the foot of the bed and, kneeling down with cotton cap in hand, breathed a short prayer. Each sprinkled the corpse with holy water and then the whole procession withdrew in the same silence with which they had entered.”