Sadism is not an infectious disease that strikes a person all of a sudden. It has a long prehistory in childhood and always originates in the desperate fantasies of a child who is searching for a way out of a hopeless situation.

For Your Own Good: Hidden Cruelty in Child-Rearing and the Roots of Violence (ed. Farrar, Straus and Giroux, 2002) - ISBN: 9781466806764