International Journal of Comparative Psychology

Scientific psychology is a search for the mechanisms that underlie behavior. Following a brief history of the comparative psychology of learning, we suggest that comparative psychologists should focus on mechanisms rather than performances, and provide an example of a simple, formal mechanism to illustrate this point.

A major goal of physiological psychology is to determine the physical basis of mental representation. Animal models are essential to this project. Dretske's influential analysis of the concept of mental representation suggests that operant and classical conditioning involve mental representation. This analysis comports well with known physiological mechanisms of conditioning, but fails to capture necessary features of mental representation at the human level. We conclude that the applicability of animal models to the problem to human mental representation is more restricted than previously thought.

Advocates of Darwinian approaches to the study of behavior are divided over what an evolutionary perspective is thought to entail. Some take "evolution-mindedness" to mean "phylogeny-mindedness," whereas others take it to mean "adaptationmindedness." Historically, comparative psychology began as the search for mental continuities between humans and other animals: a phylogenetic approach. Independently, ethologists and now behavioral ecologists have placed far more emphasis on the nichedifferentiated mental abilities unique to the species being investigated: an adaptive approach. We argue that the output of complex, dynamical systems can be dramatically changed by only minor changes in internal structure. Because selection acts on the consequences of behavior, the behavioral output of the psyche will be easily shaped by adaptive demands over evolutionary time, even though the modification of the neurophysiological substrate necessary to create such adaptive changes may be minor. Thus, adaptation-mindedness will be most illuminating in the study of cognition and behavior, whereas phylogeny-mindedness will be most illuminating in the study of their neurophysiological substrates. Similarly, a phylogenetic approach to cognition and behavior is likely to cause one to overlook our most interesting, complexly designed species-typical traits, whereas using animal psychology to exfoliate general principles of behavioral ecology represents our best hope of understanding humanity's many zoologically unique characteristics.

The comparative study of behavior requires close attention to the ecologically unique details of the environmental challenges and adaptations (both behavioral and structural) of a systematically selected range of species. It offers an understanding of which aspects of behavior change and which remain constant across phylogenetic pathways and evolutionary challenges. The General Process View of Learning (also known as the principle of the transsituationality of reinforcement, and by several other names), however, militates against study of the details of behavioral adaptations, by insisting that particular behaviors may be regarded as arbitrary instances of universal associative principles. The history of behaviorism, and of contingency theory, in particular, is largely the history of the gradual emergence and dominance of this General Process View, and of the working out of its profoundly anticomparative implications. The increasingly wide repudiation of the General Process View is providing the basis for a renewal of comparative studies of behavior.

The crisis in general psychology is identified as one of theoretical indeterminacy. An important source of indeterminacy is the form of generalization that emphasizes classification and common characters and identifies the general with the abstract. Determinate theory requires a form of generalization that identifies the general with the concrete and emphasizes genesis and interconnection. In order to overcome its crisis, general psychology thus requires the kind of evolutionary methodology that comparative psychology is, historically speaking, best prepared to provide.