Reinhold Messner has always pushed against the edges of what people thought was possible. In fact, he says he only feels fully alive when he’s faced death — and survived. Arguably the world’s greatest living mountaineer, he’s climbed all 14 of the world’s peaks above 8,000 meters -- and if that isn’t impressive enough, he was the first to climb Mt. Everest alone and without supplemental oxygen. He recounts some of these adventures in a new book called “Reinhold Messner: My Life at the Limit.” Steve Paulson caught up with him and asked how he got hooked on climbing.