On immediate function.

Behavior is a property of living organisms, not of inanimate matter. The problems of physical science are to understand how a phenomenon works; biological science adds the questions of what a phenomenon does and how something that does such things came to be. Exclusive dedication to cause-effect explanations ignores how behavior helps creatures cope with their internal and external environments. Laws of causation describe the precursors to behavior; laws of function describe the effects of behavior. The numerous instances of learning reflect the many ways that selective pressure for altering behavior on the basis of experience has been manifested. Little basis exists for assuming that the various forms of learning reflect either common functions or common processes. Instead, it seems that evolutionary processes have resulted in domain-specific learning. The rules of learning must be understood in terms of the function that the particular manifestation of learning serves for the organism. Evolutionary theory provides the framework for understanding function as well as relations between function and causal mechanisms.