formulating constructs reliable information can be obtained through direct observation and measurement. however, many aspects of behavior cannot be directly observed. intelligence is not an observable entity; it is inferred from using instruments that sample subject behavior. affective predispositions such as attitudes, interests, and opinions cannot be observed directly; they are observed indirectly as they manifest themselves in behavior. consequently, social scientists have developed constructs to explain why certain types of behavior occur. these constructs are often referred to as hypothetical constructs to imply that they are a construction of the social scientist's imagination. kurt lewin's force-field analysis is an example of a theoretical construct.