Beginning in paragraph 2 and continuing throughout the biography, how does Krakauer reveal McCandless’s character?

"My suspicion that McCandless’s death was unplanned, that it was a terrible
accident, comes from reading those few documents he left behind and from
listening to the men and women who spent time with him over the final year of
his life. But my sense of Chris McCandless’s intentions comes, too, from a more
personal perspective.

As a youth, I am told, I was willful, self-absorbed, intermittently reckless, moody. I disappointed my father in the usual ways. Like McCandless, figures of
male authority aroused in me a confusing medley of corked fury and hunger to
please. If something captured my undisciplined imagination, I pursued it with a
zeal bordering on obsession, and from the age of seventeen until my late
twenties that something was mountain climbing.

I devoted most of my waking hours to fantasizing about, and then
undertaking, ascents of remote mountains in Alaska and Canada—obscure spires,
steep and frightening, that nobody in the world beyond a handful of climbing
geeks had ever heard of. Some good actually came of this. By fixing my sights on
one summit after another, I managed to keep my bearings through some thick
postadolescent fog. Climbing mattered. The danger bathed the world in a
halogen glow that caused everything—the sweep of the rock, the orange and
yellow lichens, the texture of the clouds—to stand out in brilliant relief. Life
thrummed at a higher pitch. The world was made real.

In 1977, while brooding on a Colorado barstool, picking unhappily at my
existential scabs, I got it into my head to climb a mountain called the Devils
Thumb. An intrusion of diorite sculpted by ancient glaciers into a peak of
immense and spectacular proportions, the Thumb is especially imposing from the
north: Its great north wall, which had never been climbed, rises sheer and clean
for six thousand feet from the glacier at its base, twice the height of Yosemite’s
El Capitan. I would go to Alaska, ski inland from the sea across thirty miles of
glacial ice, and ascend this mighty nordwand. I decided, moreover, to do it
alone.

I was twenty-three, a year younger than Chris McCandless when he walked
into the Alaska bush. My reasoning, if one can call it that, was inflamed by the
scattershot passions of youth and a literary diet overly rich in the works of
Nietzsche, Ker-ouac, and John Menlove Edwards, the latter a deeply troubled
writer and psychiatrist who, before putting an end to his life with a cyanide
capsule in 1958, had been one of the preeminent British rock climbers of the
day. Edwards regarded climbing as a “psycho-neurotic tendency”; he climbed not
for sport but to find refuge from the inner torment that framed his existence.
As I formulated my plan to climb the Thumb, I was dimly aware that I might
be getting in over my head. But that only added to the scheme’s appeal. That it
wouldn’t be easy was the whole point.
...
It is easy, when you are young, to believe that what you desire is no less than
what you deserve, to assume that if you want something badly enough, it is your
God-given right to have it. When I decided to go to Alaska that April, like Chris
McCandless, I was a raw youth who mistook passion for insight and acted according
to an obscure, gap-ridden logic. I thought climbing the Devils Thumb would fix all that was wrong with my life. In the end, of course, it changed almost nothing. But I came to appreciate that mountains make poor receptacles for dreams. And I lived to tell my tale.
As a young man, I was unlike McCandless in many important regards; most
notably, I possessed neither his intellect nor his lofty ideals. But I believe we
were similarly affected by the skewed relationships we had with our fathers. And
I suspect we had a similar intensity, a similar heedlessness, a similar agitation of
the soul.

The fact that I survived my Alaska adventure and McCandless did not survive
his was largely a matter of chance; had I not returned from the Stikine Ice Cap in
1977, people would have been quick to say of me—as they now say of him—that I
had a death wish. Eighteen years after the event, I now recognize that I suffered
from hubris, perhaps, and an appalling innocence, certainly; but I wasn’t
suicidal. "