Associationists have had different responses to the problem. Some have denied that human thought is actually compositional, productive, and systematic, and other non-associationists have agreed with this critique. For example, Prinz and Clark claim “concepts do not compose most of the time” (2002: 62), and Johnson (2004) argues that the systematicity criterion is wrongheaded (see Aydede 1997 for extended discussion of these issues). Rumelhart et al. offer a connectionist interpretation of “schemata”, one which is intended to cover some of the phenomenon mentioned in this section (Rumelhart et al. 1986). Others have worked to show that classical conditioning can indeed give rise to complex associative structures (Rescorla 1988). In defense of the associationist construal of complex associations Rescorla writes,