Some sort of empirical basis is required to evaluate competing theories proposed to explain the past. If not, archaeological fieldwork does not expand our knowledge, and preference for one explanatory model over another is simply a matter of taste. Regardless of the source of theories, or the manner of data presentation, better explanations must be favored when they more fully, logically and simply explain the material patterns documented by archaeologists. This perspective gives equal weight to inductively and deductively derived ideas, although I can think of no reason not to frame questions in a broadly deductive manner when possible (Nagel 1961: 15–28). Although deductive presentation is to some degree a matter of style, it tends to generate a more logical explanatory scheme with emphasis on the explicit treatment of expected material patterns. My attempt to elaborate expected patterns for the three models presented at the end of Chapter 3 might be a bit cumbersome but it forces a formal evaluation of who says what and exactly what data favor which models. Even more importantly, it forces a formal evaluation and choice of the model that best corresponds to the current state of the data.

In this chapter, I propose that a pragmatic positivism most convincingly allows competing hypotheses to be evaluated.