"Psychopathy does not appear to be caused by poor mothering or early trauma, or to have any other nurture-based explanation. It's a genetically heritable condition that creates brains that are unmoved by the needs, suffering, or dignity of others. The elephant doesn't respond with the slightest lean to the gravest injustice. The rider is perfectly normal--he does strategic reasoning quite well. But the rider's job is to serve the elephant, not to act as a moral compass."

Jonathan Haidt, The Righteous Mind