The Rwandan genocide, the Holocaust, the lynching of African Americans, the colonial slave trade: these are horrific episodes of mass violence spawned from racism and hatred. We like to think that we could never see such evils again—that we would stand up and fight. But something deep in the human psyche—deeper than prejudice itself—leads people to persecute the other: dehumanization, or the human propensity to think of others as less than human. An award-winning author and philosopher, Smith takes an unflinching look at the mechanisms of the mind that encourage us to see someone as less than human. There is something peculiar and horrifying in human psychology that makes us vulnerable to thinking of whole groups of people as subhuman creatures. When governments or other groups stand to gain by exploiting this innate propensity, and know just how to manipulate words and images to trigger it, there is no limit to the violence and hatred that can result. Drawing on numerous historical and contemporary cases and recent psychological research, On Inhumanity is the first accessible guide to the phenomenon of dehumanization. Smith walks readers through the psychology of dehumanization, revealing its underlying role in both notorious and lesser-known episodes of violence from history and current events. In particular, he considers the uncomfortable kinship between racism and dehumanization, where beliefs involving race are so often precursors to dehumanization and the horrors that flow from it. On Inhumanity is bracing and vital reading in a world lurching towards authoritarian political regimes, resurgent white nationalism, refugee crises that breed nativist hostility, and fast-spreading racist rhetoric. The book will open your eyes to the pervasive dangers of dehumanization and the prejudices that can too easily take root within us, and resist them before they spread into the wider world.