The more Damasio learned, the more he came to appreciate so-called irrational sentiments. Emotions and feelings were not impediments to reason; they were integral. “Reason may not be as pure as most of us think it is or wish it were,” he wrote. “At their best, feelings point us in the proper direction, take us to the appropriate place in a decision-making space, where we may put the instruments of logic to good use.”