I picked up Into Thin Air a few years back because I wanted to understand something that didn’t make much sense to me. Why would anyone choose to climb a mountain that kills so many people? Everest especially. There are hundreds of other peaks, safer, quieter, maybe just as beautiful, and I couldn’t figure out what people were chasing up there; I turned over the usual explanations—thrill, ego, some private calling—but none of them felt large enough to justify the risk, so I assumed the book would clear that up. It didn’t. A …