refer to loss of cognitive ability with altitude. This is a subtle phenomenon because the climber is unaware of its occurrence. How COULD he be aware of it? It is not possible as seen in the following argument.

Suppose a high altitude climber is aware of his diminished mental (and decision making) abilities. That awareness alone would then indicate a level of cognition that runs counter to the original premise that mental capacity is wanting. As a contradiction results, the original premise must be false.

Poor decisions at extremely high altitude have the potential for fatal consequences.

A view north to Mercedario from the 18,550 foot food cache.

In principle no person is immune. I surmise that an individual of particularly clear mind at sea level is at advantage since he has more "brainpower to lose" prior to commiting serious errors in judgement.

Had we decided to remain one extra day resting at Camp Berlin it would have been an error in judgement - one that is all-too-easy to make because of the desire to rest after the long summit day ordeal.

Had we elected to separate the group on summit day it would have been an error in judgement. This option is never needed since every person performs adequately.

I never "feel" as if I need a brain tune-up while at Camp Berlin. Edward Earl poses an interesting scientific question, and I arrive at the correct solution with only a little more time than I probably would need at a saner elevation.

That said, please note this caveat - the climber always feels as if he is doing OK. THAT is, in fact, PART OF THE PROBLEM. The situation is analogous to an automobile driver who, after a few too many drinks, "thinks" that he is prepared to drive home.

The cerebral hypoxia Edward and I experience above 21,500 feet is certainly a form of impaired mental capacity. I certainly could have multiplied and divided numbers in my head - but what does it matter if you cannot correlate speakers with their words?

Emotional Issues

"There is not a day on this mountain when I did not want to go home".

        - Adam Helman on Day 8

ajor psychological forces are at work when living on a mountain for over two entire weeks. One abandons all the usual comforts of home in an (equitable?) trade-off for reaching the summit. The indoor plumbing (with free-flowing water); artificial lighting (and thus an enjoyable evening); microwave oven (and thus instant hot food); television (mind-numbing entertainment). Not to mention a comfortable bed and a hot shower.

Presumably one does not embark on a major expedition without having already relegated these objects of modern life to the back burner of one's expectations.

Nevertheless, when you add cold (very cold?) temperatures; unavailability of your favorite foods (I adore ice cream); and oxygen starvation, the pressures for a more cushy existence mount.

Often these desires manifest in extended conversation regarding what food is to be eaten at the first post-climb feast. Thoughts of meal-sized salads; nachos, pizza, and steak are commonplace.

I am absolutely certain that the vast majority of Americans would not tolerate a single night camping - let alone doing so halfway towards the stratosphere. They insist on motels when traveling, with nary a thought of how they would comply to a regimen of sleeping bag and tent on a bed of snow.

I equally suspect that the majority of Third World inhabitants would easily adapt, and accept such a lifestyle - if and only because their own experience is far more similar to overnight camping. The paucity of oxygen, however, would still be problematic unless they hale from Bolivia.

So how many of us want to go home? Edward - you too. I doubt that any naysayer speaks the truth. That is NOT demonstrating a lack of faith in the expedition, nor in the eventual success of its purpose. Rather, one simply puts up with the hardship for the greater goal to which we all are entirely devoted.

Personal Issues

his is a grab bag of assorted items - the snoring sleeper; the person who wants the same meal every morning when others desire change; those who first break down the tent while others wish to eat breakfast first; the person who continues climbing while others desperately need a break.

The most vexing and problematic issue is the person who cannot maintain the group hiking pace.

The expedition is a miniature society wherein every participant must cooperate with every other member in order for the entire team to function efficiently. When problems arise they can be discussed, and, most commonly, compromises are then made.

I own earplugs. I have eleven varieties of hot oatmeal to counter the omnipresent pancake threat. When pancakes are on-tap because it is a group breakfast, I respond by enjoying ginger/macadamia nut pancakes; pancakes with kosher "bacon" and viscous, brown sugar water (which Edward calls "maple syrup"); pancakes with raspberry jam and Norwegian gjetost cheese - the possibilities are large indeed.

However Robert Greene cannot maintain our uphill pace on both days one and two. Although in principle we all could accomodate this tardiness when establishing higher camps, to go slowly on summit day is downright dangerous. Speed is essential in reaching the top so that return to camp is possible by nightfall. Darkness at 21,000 feet, with minus zero temperatures and a blowing wind is not a good thing when sleeping bags are nowhere to be had:

People have DIED that way on Aconcagua.

Herein lies the greatest problem - how do you tell somebody they cannot climb with you because it compromises the safety and success of all remaining participants? This is most assuredly a "personal issue" par excellence.

The best of all worlds exists when the slower person understands the issues, and, in a show of great sportsmanship and moral rectitude, offers to voluntarily withdraw from the group.

However John, Edward, and I knew not what Robert thought.

I boldly relay these concepts to Robert the evening of Day 3, suggesting even that we would endeavor to pair him with another group for summit day should his pace not improve.

The following morning Robert voluntarily left the expedition, citing his great headache as the prime mover.

Either the altitude solved our personal dilemma for us; or Robert was being extremely benevolent - in effect, feigning a severe headache for the sake of ensuring our smooth run to the summit.

Robert Greene provides a trip report . It is well written, and should be read for a fuller appreciation of how and why the most heart-wrenching decision in mountaineering is actually made - to retreat before the summit.