There is every reason in the world why this book should not exist. How can you write a breezy book about such a ponderous question? How can you do philosophy by interviewing philosophers? It seems an impossible task—like getting something from nothing—but author Jim Holt pulls it off with great verve and brio.

The premise of Why Does the World Exist? is as simple as it is maddening. Holt puts Leibniz’s famous question—“Why is there anything at all; why not nothing?”—to a handful of contemporary cosmologists who have been thinking about the origins of the universe. With the unabashed enthusiasm of a kid on a treasure hunt, the author trots back and forth across oceans and continents interviewing scientists and philosophers. He also interrogates some of the great texts of philosophy, though that’s not nearly as much fun for the reader as the author’s accounts of buttonholing Oxford dons and astrophysicists. Holt’s unusual method works because his longtime interest in science and philosophy—subjects he’s written about for the New York Times and the New Yorker—makes him a particularly articulate explainer. His intellectual modesty and generosity of spirit, his eye for telling details, and his self-deprecating sense of humor make this highly theoretical book also an engaging one.

Holt’s interviews are the source of much of the book’s humor. When the author meets and greets a Buddhist scholar on the street and, after only a few words of chit-chat, plunges into the why-not-nothing question, the scholar gently bops him on the head. I laughed out loud, remembering Thrasymachus’ more ominous attempt to slug Socrates in The Republic. In fact, all the interviews are like little Platonic dialogues that, in seeking some resolution of the various puzzles surrounding the nothing-or-something question, often leave you more perplexed but also a tad wiser. My favorite answer to Holt’s Leibnizian question is the philosopher Sidney Morganbesser’s: “Even if there was nothing, you’d still be complaining!”

For those who are fascinated by discussions about the origins of the universe—and events such as the recent discovery of the Higgs boson—this is the book for you. It goes into all the sexy stuff like the big bang and the big crunch, the multiverse, string theory, and black holes. You do not have to be a cosmologist to understand it all, but it does help to have some familiarity with the scientific and philosophical issues behind the debates. Along the way from one physicist or philosopher to another, Holt spices his account with lighthearted digressions into literature, film, and music.

Holt’s guiding light is the principle of sufficient reason: for every truth an explanation, and no truth can explain itself. But in that case, where does explanation end? There’s the rub. The threat of infinite regress bedevils a lot of cosmological theories, as Holt makes plain. But the subtitle of his book, “An Existentialist Detective Story,” hints that at least some progress can be made, if only in clarifying the question.

Much of today’s discussions about the origin of the universe seem to end up in simplistic counter-positions: a bull-headed atheism that refuses even to ask the question of why (“it just is”), or a smug theism that believes it (or, rather, God) holds all the cards. It is to Holt’s great credit that he eschews easy answers and is intrigued by serious explorers of the great mystery of being. His antipathy is reserved for those who think they have all the answers: “There is nothing I dislike more than premature intellectual closure.” He can be fascinated both by Richard Swinburne’s argument that God is the simplest and most elegant explanation of the universe and by the claim of Adolph Grunbaum (the “Great Rejectionist”) that the universe simply evolved out of nothing. (There is a hilarious passage about Grunbaum’s madcap attempt to get to a restaurant in Pittsburgh, an episode that puts Holt in mind of Zeno’s paradox.) Perhaps the best character in the book, the physicist David Deutsch, is a proponent of the multiverse, or parallel-universes, theory. Holt describes Deutsch standing on his doorstep as “an improbably boyish-looking fellow with large mole-like eyes, rather transparent skin, and shoulder-length, albinoid hair. Behind him I could see great moldering heaps of papers, broken tennis rackets, and other detritus…experiments in indoor composting.” Once inside the house, Holt finds a beautiful young woman eating mac and cheese, who says nothing during the entire interview with Deutsch.

Aristotle famously said that thought moves nothing. And while  Holt (and I) agree with the sober Stagirite, there are several contemporary mathematicians who believe that thought moves everything. These newly minted followers of Plato (and Parmenides)—Sir Roger Penrose, Max Tegmark, David Chalmers, and John Leslie among others—believe that immaterial substances (numbers, the good, etc.) explain the whole universe. While Holt finds this idea riddled with logical problems, it is at the very least a nice antidote to all the crude reductionisms floating around today.

Gabriel Marcel, the existentialist thinker, liked to say that to ask the question “What is Being?” is to ask “Who am I?” Holt, too, recognizes a connection between these two questions, and toward the end of the book he addresses, albeit inchoately, the role of the self. His poignant description of his mother’s death and his reaction to it reminds each of us of our fragility as we travel through life between two nothings: the not-yet before we were born and the no-longer after we die.

When it comes to the new cosmologies, I am only a neophyte. But some questions do come to my untutored mind. First, are the paradigmatic questions “Why does the world exist?” and “Why is there something rather than nothing?” as interchangeable as the author seems to imply? The former plunges us into all the fascinating issues surrounding the origins of the material universe, but the latter may take us beyond physics into the very meaning of existence as such—the realms of metaphysics, theology, or even poetry. Here some lines from Robert Frost’s “Accidentally on Purpose” come to mind:

Whose purpose is it? His or Hers or Its?

Let’s leave that to scientific wits.

Grant me intention, purpose and design.

That’s near enough for me to the Divine.

I also wonder whether we can really find an answer to Leibniz’s question if we have not first explored the conditions and limitations of the being who asks the question? This problem is at the heart of much continental philosophy, but even in the analytic tradition, with which Holt is more comfortable, we find similar concerns, focused on the limits of language: What can be meaningfully said, and what can’t? Some of Holt’s interlocutors hint at an unavoidable circularity in the problem he’s investigating. One of them observes that every breakthrough explanation changes the very meaning of explanation. But Holt tends not to follow up on those leads. He leaves it to the reader to wonder: Are there necessary conditions for even asking, much less answering, the why-not-nothing question? And if so, what are they? But such complexity need not deter us. One of my old professors used to say that the peculiar schizophrenia of philosophy is that it continues to seek while knowing it will never be satisfied. But, he would add with a smile, that is the characteristic of any erotic practice.

The book has other shortcomings. Holt’s transitions are sometimes contrived; his conversations with European philosophers are not as satisfying as his conversations with Brits and Americans; his discussion of suffering left me more confused than illuminated. And, unavoidably, the reader is at the mercy of the author’s tastes—for example, his enthusiasm for the novelist John Updike, whose cosmological speculations are quoted at great length. Still, Holt’s book reminded me of that well-known line by e.e. cummings: “Always the beautiful answer who asks a more beautiful question.” Holt presents us with the beauty of the spheres by asking the child’s simple but profound question: Why?