This is a footnote from “How Brands Grow“.
There is a very long (too long!) history of marketing writers debating what ‘true loyalty’ is. This is a perfect example of what the twentieth century’s most famous philosopher of science, Sir Karl Popper, called essentialism: seeking to define the essence of an abstract theoretical concept (Esslemont & Wright, 1994). We can forever debate issues (like, What is true love? What is marketing?), but as these questions are simply about the definitions we decide to use there is no logical way of ever resolving them. To suggest that one approach captures the true meaning of brand loyalty, while another (by implication) does not, is bad philosophy, and bad science. Contrary to popular belief the purpose of science is not to say what things are but rather to say things about things: how they behave, how they relate to other things. Physicists can tell you a great deal about the properties and behaviour of things like gravity and mass while there is no rigid definition of what these things ‘truly’ are. Hence, this book is about what we can say about real world loyalty-type behaviour, both verbal behaviour (expressed attitudes) and overt behaviour (buying).
“Never let yourself be goaded into taking seriously problems about words and their meanings. What must be taken seriously are questions of fact, and assertions about facts; theories and hypotheses; the problems they solve; and the problems they raise” (Popper, 1976).
Marketing Science 
This is a major challenge in marketing (as well all of science). One example is the concept of “expectations” as it has undergone change in the field of marketing. Originally, “expectations” was defined as a forecast of performance; then it “evolved” into, among other things, performance “requirements” in a relationship between a customer and a brand. PhDs that were writing about this topic really never could agree as to what “expectations” is. In reality, the term is meant to describe some kind of brain or mental state (and even those terms are controversial in the field of philosophy of mind). Bottom line: many of our concepts in marketing are about aspects of human consciousness and how those “aspects” are affected by unconscious states mind and the context surrounding consumer choice. We need to be very careful in marketing when developing concepts since the very notions of “mind” and “consciousness” are themselves controversial and developing. See A Skeptic’s Guide to the Mind, by Robert A. Burton, MD.
Burton’s book sounds like a useful antidote to the highly misleading “Buyology”.
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