Alex honnold is always asked the same two questions:

Aren’t you afraid you’re going to die?

Why do you do this?

This refers to climbing thousands of feet in the air, alone, with no harness, rope, or other safety equipment. Few professional climbers have risked “free soloing,” as it is known in the climbing community. Many of them have died trying. But Honnold climbs longer and more difficult routes than anyone previously thought possible—extraterrestrially named routes like Cosmic Debris, Astroman, and Heaven. He also climbs them in record time.

“I get really tired of answering those questions over and over again,” Honnold says. But you can’t blame those who ask the questions: fans, friends, me, any rational, thinking, nonsuicidal human being. These are the obvious questions and also the ultimate ones. Why is it not enough to be one of the best climbers in the world? Why remove the protection? It’s as if Tom Brady declined to use pads and a helmet, or Serena Williams played a Grand Slam tournament in which the penalty for losing a set was beheading.

At its most elite levels, climbing is already staggeringly dangerous. Falling boulders, frayed belay ropes, avalanches, broken carabiners and bolts—Rock and Ice magazine keeps a running tally of accidents. Recent entries include: “Bolt Breaks, Climber Falls to Death”; “Impaled by a Quickdraw”; “Earthquake, Avalanche, 21 Dead on Everest.” Honnold’s free soloing has brought him wealth and international recognition, but neither of these prizes seems to be his central motivation. He is grateful for his sponsorships—The North Face, La Sportiva, and Goal Zero (Clif Bar dropped him last year out of fear that he was “taking the element of risk to a place where we as a company are no longer willing to go”)—but mainly because they allow him to climb even more terrifying walls, in places like Chad and Patagonia. Honnold lives frugally: A Ford Econoline van has been his home since 2007. And while he seems to appreciate the fame, despite some protests to the contrary, he had, until recently, conducted many of his most daring ascents in secrecy. It was only when friends, told belatedly of his accomplishments, leaked the news to climbing Web sites that his exploits came to be known.

When asked in public about the risk of falling to his death, he answers glibly: “It’ll be the worst four seconds of my life.” (This is not exactly accurate. Were he to lose his grip near the top of one of the walls he has climbed, he would fall for 14 seconds before impact.) A memoir would seem to present the perfect occasion to deliver a reflective, persuasive, intimate answer. Honnold understands this. He raises the question of motivation frequently in Alone on the Wall. But he never quite answers it. Or rather, he answers it in many different ways, none of them convincing. Taken together, however, these evasions approach a satisfying answer, which is to say, an honest one.

Alone on the Wall, true to the sports-autobiography genre, is written with a co-author, though in this case Honnold and his collaborator—David Roberts, himself an experienced climber—write alternating sections. The co-author of any sports autobiography has two main responsibilities. He or she must render the athlete’s interview responses into legible prose and also provide context and insight when the athlete cannot. Rarely are world-class athletes, particularly those in their prime, able to explain to people who are not world-class athletes what it’s like to have supernatural ability. They’ve never been without it, after all. This is a reason sports memoirs written later in life tend to be more rewarding, or more human—the athletes, having faded into mediocrity, can finally appreciate the outlandishness of their talent.

W. W. Norton

Elite athletes also tend to resist deep reflection. Were they to obsess over the pressures they face, they’d never be able to thrive in the first place. As David Foster Wallace put it, in reference to the tennis player Tracy Austin, “Great athletes usually turn out to be stunningly inarticulate about just those qualities and experiences that constitute their fascination.” Honnold describes his mentality during a solo climb as “empty” and “not really thinking.” This is to be expected. A basketball player who thinks too much is more likely to miss a crucial free throw at the end of a game; a climber who thinks too much may plunge to his death.

Alone on the Wall is a celebration of nonthinking. As he surveys the greatest accomplishments of his career, Honnold reviews his ascents in meticulous, technical detail: “The second pitch of the Zig-Zags flew by in a frenzy of hand jams and hero liebacking.” He refers to the possibility of “stepping into the void,” but never imagines the void, or what it would be like to step into it. Even when he forces himself to visualize falling to his death, his tone is matter-of-fact, indifferent: “I saw myself bouncing off the ledge below and going all the way to the ground, fracturing most of my bones as I rag-dolled down the mountain. I’d probably bleed out at the base.”

This doesn’t lead to a dark night of the soul, however. During the climb itself, suspended in air, at times hanging by the tip of a single finger, he experiences no fear. The lows are never very low, nor the highs very high. Honnold’s reaction to free soloing Moonlight Buttress, a nearly vertical 1,200-foot-tall sandstone cliff in Zion National Park, the climb that first brought him national attention: “I was superpsyched.” On climbing both Half Dome and the Nose, in Yosemite National Park, mostly without ropes, in a little more than 11 hours, beating the record time by half: “I was massively psyched.” On climbing the Yosemite Triple, three steep routes, in less than a day, without falling: “I was pretty pleased.”

This equanimity in the face of oblivion is what separates Honnold from other top climbers. Before him, the most celebrated free soloist was one of his heroes, Dean Potter. Haunted, self-questioning, audacious, brooding—Potter was the climbing world’s Baudelaire. His earliest memory was a childhood dream of flying and falling. “I always wondered as I got older if it was some premonition,” Potter said. “I started free soloing harder and harder routes, kind of proving to myself that I could take control over … the biggest fear I had: falling to my death.” Potter fell to his death in May while jumping off a cliff in a wingsuit in Yosemite.

Honnold, by contrast, projects what one friend calls a “dorky, awkward goofball” persona—Pete Sampras to Potter’s Andre Agassi. He draws the line at BASE jumping, the practice that killed Potter (“way too dangerous”), but to a layperson this seems a distinction without a difference. Before attempting his free solo of Moonlight Buttress, Honnold rehearsed the most challenging pitch on rope repeatedly, until he had memorized each move. But he soon tired of this approach, complaining that it “actually took some of the challenge out of the climb.” He free soloed Half Dome without being certain of the correct route; later he free soloed Rainbow Wall in Nevada’s Red Rock Canyon, “fourteen pitches of sustained climbing up this massive, concave, amphitheaterlike face, lots of it on tiny holds,” without scouting it at all, having climbed it only once, with protection, years earlier. “Some people might call this crazy. I prefer to think of it as badass. It definitely amped up the adventure.”

Honnold halfheartedly tries out a number of explanations for his risk taking. There is denial that borders on delusion: “I don’t like risk.” The joy of conquering a self-imposed challenge: “I do it because it’s so much fun … All this stuff is a game.” The exhilaration of a life-or-death situation: “It’s hard to untangle the various feelings, but I definitely felt alive.” The euphoria of achieving a focus so acute that “pain ceases to exist.” He rejects the suggestion that he is an adrenaline junkie: “There is no adrenaline rush,” he told 60 Minutes’ Lara Logan. “If I get a rush, it means that something has gone horribly wrong … because the whole thing should be pretty slow and controlled.” But none of these explanations is credible, because they are all available to those who use ropes.

Though Honnold’s free soloing—and the terrifying, thrilling videos of him clinging to an invisible hold in the middle of a sheer wall—is the source of his fame and, by extension, the reason for his book’s existence, he emphasizes that he spends the great majority of his time doing more-conventional forms of climbing. Much of the book dwells on his accomplishments in those realms, which are considerable. Last year, for instance, Honnold and Tommy Caldwell, another of the world’s elite climbers, were the first to complete the Fitz Traverse, a series of seven ice-covered granite spires in southern Patagonia. Honnold has broken a number of speed records, pioneered new routes, and managed astonishing feats of physical endurance. In recent interviews he has blamed the media for portraying him as an “extreme” free soloist and seemed to rue the notoriety his exploits have brought him. The solos, while of astounding technical difficulty, seem to have assumed for him a somewhat distasteful aura—as if they are stunts that have diminished his professional standing. Having entered his fourth decade, might his sense of his own mortality be evolving? If so, he doesn’t say.

Even Honnold’s peers, who call him “No Big Deal” Honnold, are puzzled by his general lack of introspection. “His conversation never drifted to places of death, love or even innate beauty,” wrote Tommy Caldwell in an essay for Alpinist about the Fitz Traverse. “It’s as if he thinks everything is either badass or boring … That’s probably part of the reason he is so good at what he does.” Caldwell is almost correct. Honnold’s ability to ignore the higher questions—to ignore death—is not part of the reason for his success. It’s the entire reason. It’s also the source of his allure. I suspect that most people who watch Honnold’s videos do not particularly envy his climbing ability. We envy his ability to forget about death.