2. The Nature and Relevance of Theories

Scientific findings are systematized and summarized mainly by theories. Theories are thus the basis for innumerable practical applications and serve to preserve and communicate knowledge as well as to develop understanding. This constitutes their central importance for all scientific disciplines. The first section describes what a theory is. This is then illustrated by the example of the Elaboration Likelihood Model, a well-known theoretical model in consumer and communication research. Typically, theories serve to help in the understanding of certain aspects of reality. Therefore, the relationship between theory and reality is discussed later (Sect. 2.2). Essential applications of theories (➔ “Relevance of theories”) refer to explanations of real phenomena and the establishment of scientific laws (see Sect. 2.3), the prognosis of events and developments, and the use of such findings for (practical) applications in reality, for example the development of strategies and decisions (see Sect. 2.4). The end of this chapter (Sect. 2.5) presents some typical scientific conclusions (induction, deduction and abduction). In all of these considerations, theories used in different areas of marketing research are the focus of attention.