Achieving the summit of a mountain was tangible, immutable, concrete. The incumbent hazards lent the activity a seriousness of purpose that was sorel… - Jon Krakauer

Most climbers aren't in fact deranged, they're just infected with a particularly virulent strain of the Human Condition.

"A month later Billie sits at her dining room table, sifting through the pictorial record of Chris's final days. It is all she can do to force herself to examine the fuzzy snapshots. As she studies the pictures, she breaks down from time to time, weeping as only a mother who has outlived a child can weep, betraying a sense of loss so huge and irreparable that the mind balks at taking its measure. Such bereavement, witnessed at close range, makes even the most eloquent apologia for high-risk activities ring fatuous and hollow." - describing the mother of Chris McCandless after learning of his starvation in the wild

When I rest I feel utterly lifeless except that my throat burns when I draw breath.… I can scarcely go on. No despair, no happiness, no anxiety. I have not lost the mastery of my feelings, there are actually no more feelings. I consist only of will. After each few metres this too fizzles out in unending tiredness. Then I think nothing. I let myself fall, just lie there. For an indefinite time I remain completely irresolute. Then I make a few steps again.