What causes addiction, and how should we treat it? Today it is understood primarily as a brain disease, yet pioneering psychiatrist Elias Dakwar argues that this is false. Instead, addiction is an existential challenge, requiring a more philosophical and multidisciplinary approach. It stems from our desire for happiness: whether addicts or not, we all struggle against meaninglessness, and resort to false solutions to our despair. Dakwar also shows how our individual capacity for self-delusion relates to our collective self-inflicted crises, from environmental destruction to social injustice. Drawing on vivid stories of his own patients, path-breaking research, and decades of clinical experience, this offers a novel framework for understanding and overcoming addiction, as well as human suffering more generally.