  Other potential sources of renewal?  The continued popularity of behavior therapy is noteworthy because it offers a potential domain of testing application for the regimen of behaviorism. Early versions of behavior therapy sought to apply restricted results from Skinnerian or Pavlovian conditioning paradigms to human behavior problems. No minds should be spoken of; just behavior—stimuli, responses, and reinforcement. Therapy shapes behavior not thought. Successive generations of behavior therapy have relaxed those conceptual restrictions.  Advocates refer to themselves as cognitive behavior therapists (e.g. Mahoney, 1974; Meichenbaum, 1977).  Clients’ behavior problems are described by referring to their beliefs, desires, intentions, memories, and so on.  Even the language of self-reflexive thought and belief (so-called ‘meta-cognition’) figures in some accounts of behavioral difficulties and interventions (Wells 2000).  One goal of such language is to encourage clients to monitor and self-reinforce their own behavior. Self-reinforcement is an essential feature of behavioral self-control (Rachlin 2000; Ainslie 2001).