Runkel reviews current psychological research methods (i.e., 'casting nets') and tells the reader in an easily understandable way what kinds of information the methods do and do not provide. Any research method is a tool appropriate in some but not all situations. The mainstream research tools of psychology are not sufficient to explain individual behavior and its causes.
Following this review, the reader is familiarized with the concept of causation and with W.T. Powers's Perceptual Control Theory, the framework necessary for a change in perspective on human behavior (i.e., 'testing specimens'). The author explains how an appropriate investigation of causation in individual human behavior should be designed and then expands the view to an interaction between individuals.
