In his book Con­ver­sa­tions with the Earth, Ger­man geol­o­gist Hans Cloos described the moment when he “became a geol­o­gist for­ev­er.” It did not hap­pen at uni­ver­si­ty. It did not hap­pen with the pass­ing of an exam or the award­ing of a degree. It hap­pened one morn­ing in Naples, Italy, when Cloos opened the win­dow of his hotel room and saw the smok­ing cone of Vesu­vius loom­ing above the still-sleep­ing city. At that moment he had the real­iza­tion that moti­vat­ed a life­time of cre­ative work in geol­o­gy: The Earth is alive.