Ancient Greeks and Romans did not share our idealization of isolated geniuses, working alone to think through the knottiest problems. Such scenes—Descartes in his secret retreat, calling everything into question, or the excommunicated Spinoza quietly reasoning to himself while grinding lenses—would eventually become our dominant emblem of the life of the mind. But this vision of proper intellectual pursuits rested on a profound shift in cultural prestige, one that began with the early Christian hermits who deliberately withdrew from whatever it was that pagans valued:
