FROM 10,000 FEET, Twight and I hauled to 11,200, made a carry up around Windy Corner to the 14,200 camp, and then came back down for the night, stashing our skis in the snow at 12,500 just above Squirrel Hill. The next day it was storming, but Twight and I couldn't bear hanging out in the same tent together, so we moved up toward 14,200, hardly speaking. The day before, both Squirrel Hill and Windy Corner had been so icy we were obliged to strap on our crampons and carry our skis. Thus, when we reached the skis the next day, I suggested we leave them there. We would only carry them up and then carry them down, hardly using them again. Twight didn't respond. He just started loading his boards onto his sled.

"Hey!" I said, shouting into the wind. "We're having a discussion."

"I'm not!" Twight shouted back. "I've decided."

"For yourself, or for the team?"

He gave me a quizzical look, and I wondered if it had never occurred to him that we were a team, or perhaps even that mountaineering is a team sport.

"Point taken," he screamed, and finished strapping his skis to his sled.

Later he shared his lunch with me. It was a peace offering, and as we ate, I began to realize that he wasn't enjoying my company any more than I was enjoying his. This climb was only a warm-up for Twight; in June he planned to attempt an extreme route on McKinley's South Face (and would succeed).

I was mulling over our unexpected discordance when, halfway through the corridor of crevasses on Windy Corner, it struck me that I didn't have a clue why Mark Twight climbs. For 25 years I had believed that climbers climbed for the same reason that painters painted or writers wrote or composers composed: because they loved it.

How absurdly callow.