Anthony Kronman, age seventy-one, may be the world’s most fulfilled man. A professor at Yale Law School for thirty-eight years, he has a happy marriage and four children. He swims a mile every day and is an expert fisherman with rod and spear. He lives in an impeccably decorated house worthy of Architectural Digest. He has written six books, about law, legal ethics, and education, and, last year, published his seventh, an eleven-hundred-page exploration of his personal theology, called “Confessions of a Born-Again Pagan.” By integrating the ideas of many of the world’s great thinkers—Aristotle, Aquinas, Augustine, Spinoza, and others—he has found “a third way, beyond atheism and religion, to the God of the modern world.” He suspects that he might have found the meaning of life.

Kronman’s office at Yale Law School is tidy and calm. In his desk drawers, the pencils and paper clips are perfectly aligned. His bookshelves are organized into categories: metaphysics, theology, biology, history, law. A small side table holds busts of Aristotle, Socrates, Plato, Freud, and the eleventh-century Persian philosopher Avicenna. Kronman’s book is similarly organized, and is manifestly the work of a lawyer-philosopher. First, he explains the Greek view of life, as it was expressed by Aristotle; then he describes the Judeo-Christian view, as espoused by Augustine and Aquinas; finally, he explores atheism. In each case, he shows why the best possible version of each world view is unsatisfying. He concludes that “born-again paganism”—a theology of his own invention, holding that God and the world are the same—is the only truly convincing way to understand our place in the universe.

It’s not easy to read “Confessions of a Born-Again Pagan.” The book weighs four pounds; after carrying it on the train for a few days, I had to give up and read it on my phone. The arguments are twisty and detailed. One introductory chapter focusses on Melanie Klein, the psychoanalyst, and her theories about gratitude. To be successful in life and love, Klein thought, we need to feel gratitude, but many people can’t accept their dependence on others, and so end up resentful instead. At first, it’s unclear what this has to do with born-again paganism; only after many pages does Kronman argue that the Abrahamic religions, especially Christianity, make it hard to be grateful enough for life. The ancient Greeks believed that the world simply existed; they never imagined a perfect creator who gave us everything from nothing. Kronman writes that, faced with such an unmatchable gift, we cannot help but have our gratitude toward God curdle into resentment. Like teen-agers, we rebel against the caretaker upon whom we depend too completely. From this rebellion flows the anxious character of modern life—technophilic, self-centered, willful, and litigious.

As a born-again pagan, Kronman doesn’t believe in a creator. When he uses the word “God” in his “Confessions,” he refers not to a deity but to “the infinite God of the world.” Writing about Kronman’s book in the Times, David Brooks worried that born-again paganism would lead to “laxness”: “It throws each person back on himself and leads to self-absorption,” he wrote. But Kronman doesn’t see his theology as inward-looking. He finds it electrifying and eye-opening to think of the world as divine, along with everything and everyone in it.

Reading Kronman’s “Confessions,” I wondered if its author would be like Mr. Casaubon, from “Middlemarch”—a pale, stooped, carrel-dwelling monomaniac who lives entirely in his mind. In fact, Kronman is fit, graceful, sociable, even ebullient. In the right light, he resembles Richard Gere. He seems altogether too cheerful to have spent nine solitary years mounting a pagan assault upon the skeptical ramparts of modernity. He is untroubled by the fact that very few people—not even his colleagues—are likely to read his book. “The questions that I’m obsessed with just don’t bother other people as much they bother me,” he said, in his office. He speaks with precision and emphasis—a lawyer making an argument. “Most people take note of the fact that we live in time; that things come and go; that we come and go; that nothing we do lasts; that accidents befall us; that shit happens. But they aren’t stopped in their tracks by the question ‘Is there anything that isn’t touched by time?’ There are only a few people who, once this question comes to them, can rarely think about anything else.”

Kronman’s philosophical quest grew out of a blissful childhood. He and his brother Michael were surfer kids in mid-century Los Angeles. “It was the best place, the best time in the world to grow up,” he told me. His father, Harry, had trained as a rabbi before rebelling and becoming a Hollywood screenwriter, penning episodes of “Gunsmoke,” “The Untouchables,” and “The Fugitive.” His mother, Rosella Townsend, was born in Youngstown, Ohio, into a family of devout, literalist Christians; she moved to Los Angeles, became an actress, and, under the name Rosella Towne, starred in dozens of Hollywood movies. (Publicity stills for 1939’s “Code of the Secret Service” show her cheek to cheek with her co-star Ronald Reagan.)

Kronman and his father spent weekends deep-sea fishing, and, miles from land, they encountered whales, porpoises, and sharks. With his mother, he “talked about the great questions of the universe.” Years earlier, a boyfriend—the legendary Disney animator Frank Thomas—had broken up with her after she confessed that she’d never heard of Freud; in response, she entered psychoanalysis and became a committed autodidact. Kronman has a vivid memory of sitting with her in their garden, which was fragrant with jasmine and gardenia. While she smoked Kents and sipped a gin-and-tonic, they discussed Camus and existentialism. “This is the truth!” she said. He was eight.

Kronman got a Ph.D. in philosophy at Yale. He was in psychoanalysis himself when he finished his dissertation, in 1972; he didn’t want to break it off, so he enrolled at Yale Law School. After teaching, briefly, at the Universities of Minnesota and Chicago, he returned to Yale, in 1978. In 1994, Kronman became the dean of Yale Law School; he held the post for a decade. He managed the faculty, gave talks at law firms and bar associations, oversaw the renovation of the law library, and, in general, lived the glamorous life of an academic executive. Kronman admits that he “really liked walking into a room and being introduced as ‘the dean of Yale Law.’ ” Still, he said, “It’s a weirdness about me, maybe, that I’m so happy and effective in the company of other people, and, on the other hand, really don’t give a shit.” Amid meetings with donors and professors, while teaching contracts and tax law, his mind kept returning to the question of what, if anything, his daily life had to do with eternity. Did anything exist outside of time, or was it all fleeting and temporary? If nothing lasted, what was the point?

Kronman sees born-again paganism as inherently democratic. It “divinizes the distinctiveness of every individual,” he writes; it asks us to acknowledge that we regard those we love as infinitely valuable, and encourages us to remember that even people we don’t know—our fellow-citizens—are regarded that way by the people who love them. He finds that his religious inclinations are best captured by the word “reverence,” which he defines as “an attunement to the infinite horizons of familiar objects.” Despite having spent, in total, forty-five years at Yale, he often stops in the middle of the street to admire buildings, statues, and vistas he has seen many times before. When he does this, he grows silent. “I think you can train yourself, through a kind of discipline, to be better prepared to be knocked back by the unexpected vastness of a common thing,” he told me.