Dr. Marc D. Lewis, a neuroscientist who questions whether addiction is a disease in a scientific sense, gave the 17th P. Browning Hoffman Memorial Lecture in Law and Psychiatry. He argued that addiction is better understood as a learning process, drawing on case histories, including his own, to support his arguments. Dr. Nassima Ait-Daoud, director of the UVA Center for Addiction Research and Education, offered a response to Lewis's argument. UVA Law professor Richard J. Bonnie introduced the speakers.