‘It is perfectly possible to live without gods,” Roberto Calasso writes in “The Celestial Hunter.” “It is more difficult, however, to live without the divine.” This thought explains the persistence of ancient mythology within secular society — such as the siren (used in the Starbucks logo), the staff of Hermes (the symbol of medicine) and even the origins of our days of the week. While myth is fiction posing as history and cosmogony, its function is to connect humans with the divine. A bridge to the invisible, myth is marked by the visible — statues and images, plays and rituals. Every culture has its own, but in “The Celestial Hunter” Calasso focuses on Greek myth, with supporting references to India, Egypt and Rome. Armed with the vast library of his mind, Calasso journeys into this territory to explore the caverns that lie beneath our modern thought processes and belief systems. That is, he is hunting for truths in places where meaning is ambiguous.

Now almost 80, Calasso, the publisher of Adelphi Edizioni in Milan, has been called “a literary institution of one.” In 1983, he embarked on an ambitious project to explore the forces that drive civilization. “The Celestial Hunter” is the eighth volume in the series that began with “The Ruin of Kasch,” which examines Romantic nationalism and the rise of the modern state but is really about, in the words of Italo Calvino, “all the things that have happened in human history.” Called a “master of obliquity,” Calasso has a style that is at times obscure and impenetrable; unlike most writers of contemporary nonfiction, he never explicitly articulates his point — giving you the wild feeling of swimming in the open ocean.

He likes to start his short sections with declarative, aphoristic sentences that give pause. “One who writes is following the animal guide,” is one example. “When two shamans met, it was never clear what would happen,” is another. Or: “Discovering sacrifices, for the Vedic gods, was like Western mathematicians discovering irrational or transfinite numbers.” Yet Calasso follows these opaque openings with meandering paragraphs that give the reader the experience of trying to catch a fish with your hands — the moment you think you’ve grasped something, it slips away.

The title refers to Orion, and the early chapters focus on him and other hunters: Artemis and Apollo, Procris and Clymene. Calasso has an epic ability to tell the great stories as One Great Story. For instance, in the chapter “The Brief Age of Heroes,” he writes: “To capture the Golden Fleece, to hunt the Calydonian Boar, to fight the Trojan War: three times — and only for those three times — did the heroes gather for an expedition. For the remains of an animal, to kill an animal, to win back a woman. No other reason could be sufficient for the heroes to act together. There were three patterns of events: In the first, a monster was killed. In the second, a powerful animal was hunted. In the third, men killed one another. First kill the monster, then hunt, then kill one another. It was the epitome of all that had happened since primordial times.”

Along with such insightful consolidating passages, Calasso puts thinkers who lived centuries apart in conversation with one another. Throughout “The Celestial Hunter,” he threads Simone Weil through Euripides, Plato and Plotinus. And as he pulls together these literary seams, Calasso shows that he has a point after all. In a later chapter, he implies that civilization not only culminates in literature but begins in literature. To him, the Greek hunter stories contain the seeds of the novel, with their representation of our perpetual unrest, ambiguous emotions and self-destructive impulses. In other words, the key to understanding the modern human mind is found in ancient hunter myths.

Hunting, Calasso contends, is what transformed us into humans, when the prey became predator. He calls hunting “the first art for art’s sake.” Gods hunt, but they do not eat. Humans hunt, but it is a “nonessential, gratuitous activity,” he writes. And indeed, our primate ancestors survived for tens of millions of years on fruits and roots, before beginning to eat meat about 16 million years ago. That is, we kill even though it’s unnecessary. That’s why Calasso sees hunting as an act of sacrifice, a ritual for alleviating the guilt from killing animals, a way to console ourselves “for death with acts of murder.” This method of consolation later found expression in ritual blood sacrifice, which was thought to provide “kátharsis,” or purification. Calasso claims that replacing the act of killing with a retelling of it was how theater arose, which is why there is always a kátharsis at the end of a Greek tragedy. From hunting, to blood sacrifice, to literature.

In “The Unnamable Present,” the ninth book in this series (published in translation last year ahead of the eighth book), Calasso writes: “If so many human tribes have celebrated sacrifices in so many different places and ways, there must be some deep reason for it. Indeed, a tangle of reasons that can never be unraveled.” And maybe this is what Calasso is doing with “The Celestial Hunter” — trying to unravel a tangle of reasons that can never be unraveled. By the end of the book, I felt that the fish ultimately got away. Calasso left me in the middle of the ocean, exhausted and unsure what I was doing there.

Yet perhaps that’s just his point.

The Celestial Hunter

By Roberto Calasso

Translated from the Italian by Richard Dixon

Farrar, Straus and Giroux.
450 pp. $35