ABSTRACT
Psychologists have rudimentary knowledge of the structural patterns in their domain. This knowledge provides the foundation for probing beyond the appearances of conduct and for making sense of the body of reliable knowledge already available. This chapter develops an account of this foundation by discussing both the ubiquity of end results and equifinal classes in conduct and the nature of actions as entities that comprise end results and equifinal classes. The bodily activities that most obviously produce end results consist of two classes: postural activities and movements. Postural activities support, balance, and right the body according to the laws of physics. Movements are superimposed on a postural background, and they provide proprioceptive and other stimuli that elicit postural adjustments. Instrumentality is always of the body, but reactivity is of the body and of objects outside the body. Reactivity has to do with whether bodily behavior can change its surroundings.
