In 1960 Chuck Pratt and Yvon Chouinard climbed a new route on Middle Cathedral, in Yosemite, and were forced by darkness to bivouac on a ledge.

“I had shorts and a T-shirt on,” Chouinard recalls. “He had long pants and a sweatshirt. We were both freezing. In the middle of the night Pratt says, ‘Chouinard, I know this is going to disgust you, but if we don’t embrace we’re going to die.’”

I originally heard a coconut-telephone version of that story from my friend Tom, who had a thematic variation of his own: of the time he persuaded a woman he liked to come climbing. The descent from their route was complex, he got lost, and they had to hunker down in the dark, both in shorts and T’s. She was so pissed and disgusted, he told me, that hugging for warmth was “out of the question.”