The spread of drug use

Rachlin or Schelling?

Hans Olav Melberg

Howard Rachlin has written that ”addicts are addicts because they are lonely” (Rachlin 2000: 145, emphasis original). This claim is part of his “relative addiction theory” and the purpose of the first section of this chapter is to present and evaluate some aspects of that theory. To that end I use findings emanating from a survey of about 500 drug users in treatment, as well as large surveys of the general population. The use of this evidence in turn raises the question of what, if anything, can be learned about the causes of addiction by asking drug users. For instance, Davies (1997a, 1997b) claims that such surveys shed very little light on the causes of addiction and the second part of the chapter discuss this view. In the third section I focus on social interaction, not as a variable in an explanation (as Rachlin does), but as a mechanism in the sense used by Elster (1998) and Schelling (1998). I exemplify this by exploring a small model of two mechanisms: observational learning and the dynamics of social stigma.