One of the mysteries of drug addiction is why people start to use drugs that are known to be addictive. Prior research has found that people generally under-predict the impact on their own future preferences of visceral states, such as hunger, thirst and fear that they are not currently...

Conventional wisdom once held that the demand for addictive substances like cigarettes, alcohol, and drugs was unlike that for any other economic good and, therefore, unresponsive to traditional market forces. Recently, however, researchers from two disparate fields, economics and behavioral...