Taming the boojum: Being theoretical about peculiarities of learning.

The case of the "biological constraints" movement in mid-20th-century psychology provides a reminder of the weight of psychology's reliance on theory and theory-driven methods. By 1980, a critical mass of demonstrations of the specificity of learning had eroded faith in general-process approaches. A common reaction was to call for a biological orientation. However, this proved not as straightforward as it had seemed, and much of the ostensibly biological research that followed was atheoretical. The successes in this context were due to careful theoretical work by people who appreciated the aims of the involved sciences and the interdependence of the aims with methods. Michael Domjan slowed the field's haphazard rush into ostensible biological research, and rather urged adoption of principled biological approaches. In 1982, his positive recommendation was for comparative psychology to begin to live up to its name, and adopt principled comparative methods as practised in biology. Although lauded, few followed this recommendation. Indeed, even Domjan's own subsequent research was mostly not comparative in the way he had described, but rather involved single species, guided by a behaviour systems approach. With reference to two major perspectives associated with Domjan-comparative methods and behaviour systems theory-I present Domjan's challenge not as being to make our field comparative per se, but to make it theoretical. This challenge remains current.