In this episode we talk to Dr Marc Lewis,  a neuroscientist and former professor of developmental psychology. We explore what addiction is from a neuroscience perspective, including why Marc does not consider it a disease, despite changes to the brain. We discuss how addiction relates to habit, compulsion, and how these can be understood as functions of the brain and human behaviour. Marc also talks about his own alcohol use and reflections about alcohol as a complex drug - both good and bad. Marc has authored or co-authored more than fifty journal articles in neuroscience and developmental psychology.  His first book, Memoirs of an Addicted Brain, is the first to blend memoir and science in addiction studies. His last book, The Biology of Desire,  refutes the medical view of addiction as a brain disease through both neuroscience and real world explorations of addiction problems.