Reinhold Messner, the first person to climb all 14 of the planet’s peaks higher than 8,000 metres, is probably the finest high-altitude mountaineer in history. His list of astonishing achievements on dangerous ice-clad crags includes the first solo ascent of Mount Everest without use of oxygen. Yet as he sat exhausted at 26,000 feet with two days still to go on that pioneering ascent, he thought of an eccentric Englishman ‘tougher than I am’ who had set out before him with one crippled arm and no crampons, let alone knowledge of some basic climbing techniques.