TheoryA theory is a statement or group of statements that explain “how” and “why”some part of the world works, and a theory helps researchers make new theoretical predictions about the world. Theoretical predictions become hypotheses tobe empirically tested. Theories must be continually tested with different peoplein different contexts to determine their accuracy and conditions of applicability.Some theoretical predictions will apply broadly. The operant conditioning principle of positive reinforcement (i.e., the frequency of occurrence of a behaviorincreases following reinforcement) applies very broadly. Other predictions willdepend on person, place, context, and the operation of other variables. For example, Roth and Fonagy (2005) explain that psychotherapeutic research must focuson “what works for whom.” As you might guess, theories are therefore excellentsources of researchable ideas.Leon Festinger’s (1957) theory of cognitive dissonance is an example of atheory that stimulated an extraordinary amount of research in the decade thatfollowed its publication. From this theory, Festinger and Carlsmith (1959) hypothesized and validated the less-than-obvious prediction that, after completinga boring task, participants who were given 1 to tell a “stooge” that the boring task was interesting and fun actually stated that they had enjoyed the task morethan did the participants who were given 20 to do the same thing. The theory ofcognitive dissonance continues to impact recent research as its interactions withadditional variables are understood (Cooper, 2012).The four sources of research ideas—everyday life, practical issues, past research, and theory—barely scratch the surface of circumstances that can inspire acreative idea. The important issue is not the identification of sources of ideas butthe generation of these ideas as illustrated in Exhibit 3.1. In fact, the best research ideas often come from integrating theory, past research, and practical issues. Oneway of looking at this integration is to view practical problems as providing motivation to study a problem. The research literature provides you with a knowledgebase relating to the practical problem and theory helps integrate the knowledgeand gives insight into the practical problem in a way that cannot be achieved justfrom the research literature. To develop researchable ideas requires the development of a way of thinking. You have to develop a questioning and inquisitive approach to life, see what answers might already be available, and build on what isknown to produce something better.