Jon Krakauer is my favorite writer about climbing. He's a freelancer who writes for Outside (the premier "outdoorsman" magazine) and has also published several books.

His first bestseller was Into the Wild, about a dreamy, liberal 20-something, Christopher McCandless, who decided to go "walkabout" in the American West -- and ended up dying of starvation in an Alaskan hunter's preserve. But Krakauer's second bestseller, Into Thin Air, will tell you more about climbing Everest than books by most professional climbers, because Krakauer's writing is so illuminating to the layman.

In 1996, Krakauer was sent on assignment by Outside to join one of the ubiquitous commercial expeditions climbing Mount Everest, the tallest mountain in the world (in the sense of rising the highest above mean sea level). Unlike many of the people on the trip, Krakauer actually had extensive climbing experience -- though nothing in the Himalayas or the Karakorams, which are the only ranges that boast 8,000-meter peaks (a little over 26,000 feet).

In a ghastly tragedy that year, a number of climbers were trapped high up Everest by a terrible blizzard, and nine people died on a single day -- including two very experienced guides. Into Thin Air is Krakauer's account of that ill-fated climb; he summited and made it back, but most people on his expedition died (one other survivor, Beck Weathers, was left for dead but managed to stagger to his feet and make it back alive).

Some of the other surviving guides and climbers dispute some of the things Krakauer says about them, so take the book as one survivor's account rather than as history; but when Krakauer writes about what it's like climbing to such altitudes, there is no dispute.

All the various techniques for getting up a sheer rock face are collectively called "technical climbing." But Everest is not primarily a technical mountain, not like K2. The real killers (literally) on Everest are the cold, which can freeze you solid, and especially the thinness of the air: the latter leads to hypoxia (lack of oxygen), which seriously impairs the climber's mental faculties.

That is what kills more people than anything else on Everest: above 8,000 meters, or lower if they come down with High Altitude Cerebral Edema (HACE), their brains shut down, and they do stupid things. They forget to rope in, they forget to turn on the trickle of oxygen from their bottles, they neglect to put on their crampons (spikes on your boots to keep you from slipping), or they step off a cliff because they didn't notice it was there.

From Into Thin Air:

A baffling ailment, HACE occurs when fluid leaks from oxygen-starved cerebral blood vessels, causing severe swelling of the brain, and it can strike with little or no warning. As pressure builds inside the skull, motor and mental skills deteriorate with alarming speed -- typically within a few hours or less -- and often without the victim even noticing the change. The next step is coma, and then, unless the afflicted party is quickly evacuated to lower altitude, death....

[Dale] Kruse [who came down with a serious case of HACE on this expedition] was having an incredibly difficult time simply trying to dress himself. He put his climbing harness on inside out, threaded it through the fly of his wind suit, and failed to fasten the buckle; fortunately, [Scott] Fischer and Neal Beidleman noticed the screwup before Kruse started to descent. "If he'd tried to rappel down the ropes like that," says Beidleman, "he would have immediately popped out of his harness and fallen to the bottom of the Lhotse Face."

"It was like I was very drunk," Kruse recollects. "I couldn't walk without stumbling, and completely lost the ability to think or speak. It was a really strange feeling. I'd have some work in my mind, but I couldn't figure out how to bring it to my lips. So Scott and Neil had to get me dressed and make sure my harness was on correctly, then Scott lowered me down the fixed ropes." By the time Kruse arrived in Base Camp, he says, "it was still another three or four days before I could walk from my tent to the mess tent without stumbling all over the place."

And now, at long last, with that colossal introduction out of the way, let's take a look at the AP article about David Sharp that inspired this lugubrious post. Here are the facts on a nutshell:

Down from Everest's summit in the advance base camp, exhausted climbers returned to congratulations, drinks and blessed rest after the day's conquests.

But David Sharp, last spotted hours earlier near the mountain's pinnacle, was not among them that evening, May 14. Still, the experienced climbers who were his friends were not overly concerned.

Dave Watson assumed his friend had crawled into an unoccupied tent at one of the high camps to rest. Sharp had turned around just shy of the summit twice before, so Watson knew the Briton was a smart climber. But he also knew Sharp thought of this as his last trip to Everest and was determined not to leave in defeat.

During the next two days, several climbers tried to help Sharp, but there was little they could do. And finally, on May 16th, Sharp died at 27,760 feet, in a cave known as the last resting place of a climber from India, dubbed "Green Boots," who had died on Everest a decade ago.

I don't know exactly how the AP writers, Allen G. Breed and Nepalese correspondent Binaj Gurubacharya, mean the next question they ask: "Did David Sharp have to die?"

If they mean the existential question -- as in, was it really necessary to his life to summit Everest? -- the answer would pretty obviously have to be "Yes," since this was his third attempt. But if they mean the more pedestrian (and flippant) "why were the other climbers so cruel and inhuman as not to drop everything to save him," as context indicates, then the answer lies in what I described earlier: the surreal and alien world above 25,000 feet, called "the death zone." (Gurubacharya is from Nepal, but we have no evidence he has ever been a Sherpa or has climbed that high.)

By the time any climber is in the death zone, even with supplementary oxygen, he is himself on the knife-edge of survival. His brain has mostly shut down, and his body is well along that same road. It's said that strength won't power you up Everest, because your strength is guaranteed to fail; and it's not your knowledge of climbing, because your brain will fail. What gets you to the summit is sheer stubborn will power.

I mentioned the oxygen bottles that climbers wear, but it's not what you probably think. They're not breathing air like a scuba diver would. Climbers only supplement their breathing with a thin trickle of oxygen, just enough to keep conscious; otherwise they would quickly burn their supply (in half an hour or less) and be left with nothing.

If you've never been at that altitude -- or equivalently, in a hypobaric pressure chamber, or in a jet at 30,000 feet that loses cabin pressurization or mask air supply -- you may not realize what hypoxia does to your mind. Climbers are only dimly aware of their surroundings. One of the guides on the 1996 expedition that Krakauer was on repeatedly reported that all the spare oxygen bottles the team had brought along were empty; in fact several were full. The guide didn't notice, because his brain was only running on one cylinder.

Thus, most of the climbers who passed Sharp, either headed up or down (more climbers die descending than ascending), were themselves in extreme survival mode and also running on insufficient oxygen. They probably could not really grasp Sharp's situation. Even so, they could tell he was in distress, and many tried to help him. On the 14th:

In the glare of his headlamp, Woodward could see a man, still clipped onto the red-and-blue guide rope, sitting to the right of the dead Indian ["Green Boots"], his arms wrapped around his knees. He had no oxygen mask on, and ice crystals had formed on his closed eyelashes.

Cameraman Mark Whetu yelled at him to get moving, but there was no response.

"The poor guy's stuffed," Woodward thought, believing the man was in a hypothermic coma and beyond help.

No one radioed down to expedition leader Russell Brice about a rescue. After pausing just long enough to unclip from the rope, pass Sharp and clip back in, the group trudged on.

Would Woodward have tried to do more if his brain was functioning like it would at, say, the advanced base camp (ABC) at 21,300 feet? It's hard to say. But the additional 6,400 feet of elevation meant that everyone was mentally impaired.

About 20 minutes later, a group of Turkish climbers from Middle East Technical University's mountaineering club reached the alcove and also saw Sharp. The group's Sherpa, Lapka, urged the climber to get up and keep moving.

Sharp did not speak, but waved them off.

So Sharp was actually responsive at that point. It's unlikely that anyone in the Turkish group had any idea that Sharp was in any worse shape than many people are at that stage of the climb.

Maxime Chaya had been first up the mountain that day and had passed the notch before the others, but had noticed no one. The beam from his headlamp was weak, and Chaya was focused on his goal of becoming the first Lebanese citizen to summit Everest....

It was a joyous descent until they reached the rock cave around 9:30 a.m. The sun was shining brilliantly, and this time they could not miss Sharp and his red - not green - boots.

Chaya radioed Brice....

Chaya told Brice that Sharp's legs appeared to be frozen to the knees, his arms to the elbows. Dorjee had attempted to give the man oxygen, but there was no response.

"There's nothing you can do, Max," Brice said.

Brice reminded Chaya that he had only about 90 minutes' worth of oxygen left. All of his Sherpas were helping clients down the mountain, and there weren't enough people to carry an unconscious man down tricky passes of ice and loose scree.

Even exhausted beyond the imagination of anyone who has not climbed such a peak, with a fried brain and a body that barely can be moved, several climbers nevertheless tried to rouse Sharp, talk to him, and radio down to the base camp about his condition. But if the AP believes they could have carried him down the mountain themselves, in the condition they were in, they're being completely unreasonable.

When the Turkish team, descending now, encountered Sharp again, it was already in rescue mode: a team member stricken with acute altitude sickness was being evacuated.

Another climber, Eylem Elif Mavis, also descending from the summit, found Sharp in what appeared to be a hypothermic coma. She and her Sherpa, Nima, tried to hook one of their own precious oxygen bottles to Sharp's regulator, but the device did not work....

Phurba Tashi, Brice's chief Sherpa, was descending with some others at 11:45 a.m. and was wearing a video camera on his helmet. Bending toward the shivering man, he asked his name. Whether because of the rising temperature or the oxygen Dorjee had given him, Sharp was somehow able to respond.

"My name is David Sharp," he said, according to some accounts. "I'm with Asian Trekking, and I just want to sleep."

The Sherpas administered oxygen and tried to get Sharp to his feet, but he kept collapsing.

They shifted Sharp a few feet into the sun, then headed down the mountain.

What in heaven's name does anybody think should have been done? It's impossible to send a helicopter that high; at 27,000 feet, there's no air for the rotors to bite. Nobody had the forethought to bring along a sled, even if anyone had the human capabilty to pack such baggage (high-altitude climbers routinely strip their weight to the bare minimum, even cutting their toothbrushes in half to save an ounce or two). And at that altitude, you can't just flip a comatose body across your shoulders and toddle off.

There is a reason for the term "death zone;" everybody who sets out already knows how fatally dangerous such climbs can be. Unless we ban all such ascents -- and somehow get Nepal, China, Tibet, India, and Pakistan to go along with the idea -- there are going to be deaths at the top of the world.

David Sharp made too many foolish mistakes, several before leaving Camp 4:

• He carried only a single bottle of oxygen;
• He carried no radio;
• He set out too late in the day for the ascent;
• And he was climbing alone, on a "no frills" expedition package from Asian Trekking.

That is the sense in which I said earlier that he was dead before he even left Camp 4 (27,231 feet), the camp from which climbers start the final assault on the summit (on the Northeast Ridge route).

"It almost looks like he had a death wish," said Maxime Chaya.

The reporters ask a series of questions which, if they're not rhetorical, seem to have oddly obvious answers:

Why did no one try to administer high-altitude drugs - which most climbing teams carry with them - to stimulate Sharp's breathing and relieve possible brain swelling?

Probably because the teams that found him either didn't have those drugs, or had already used them up, or thought he was beyond hope; their primary responsibility is to their own team members.

Could a couple of hours of high-flow oxygen have revived Sharp enough to get him moving?

Doubtless. But that would require more bottles of oxygen than any climber could possibly carry.

Why do people who passed Sharp within minutes of each other have significantly different recollections of his condition?

Because his condition probably changed from minute to minute, even from second to second!

UPDATE: The death-rate statistics below have been corrected.

That is the nature of such altitudes: everyone suffers, to some degree, what Sharp suffered; most survive the ordeal, but about one out of 29 of those who summit do not return to base camp alive. (That number for K2 is 1 out of 7 dying during descent, and for Denali it's 1 out of 590; all of these numbers are for climbers in the spring, the peak climbing season, and cover climbs from 1980 through 2002.)

(The overall death rate on Everest is significantly lower, 1 out of 54, because the baseline includes many climbers who get only part way up, realize they are not in good enough shape or out of their skill league, and turn back while it's still relatively easy to return. Nearly 72% of Everest climbers give it up before summiting.)

High-altitude mountaineering is a deadly, deadly sport... and the deadliest mountain in the world to climb is probably K2 -- almost as high as Everest, but highly technical climbing.

Here is what I think is the primary misunderstanding of the AP article:

Nearly two weeks after Sharp's death, Australian climber Lincoln Hall was rescued from even higher on the mountain after being left for dead and spending a night exposed to the elements. It took more than a dozen Sherpas and 50 cylinders of oxygen, but Hall - like [Beck] Weathers [in 1996] - walked down under his own steam.

This is presented, it seems to me, as a condemnation of the rescuers, who are thus indirectly accused of not doing enough to rescue poor David Sharp. They managed to get Lincoln Hall down, the reporters seem to accuse, why didn't they do as much for Sharp?

But this is the key: nobody is ever "rescued" from that high on a mountain; you only survive if you can rescue yourself. The "rescuers" are just there to help; you have to do the heavy lifting on your own.

Lincoln Hall walked down; David Sharp did not have the will. Hall lived; Sharp, in his red boots, died alongside "Green Boots," making a macabre, Christmas-y display. But that is the nature of the mountain; that is the realm you enter at the top of the world.

"Abandon hope, all ye who enter here." But hold tight to your will, because the human will, not hope, is what may -- may -- get you downslope more or less intact.