The language of heat permeates the world of our attractions and repulsions. We divide people around us into those who are warm-or cold-hearted. We say an attractive person is “hot.” We warm up to new ideas, get cold feet if something’s too threatening and blow hot and cold if we’re undecided. We distance with a cold stare, beckon with a warm smile, take time to cool down after heated arguments and lose ourselves in the fire of passion. Clearly, temperature is a hot topic for humanity.