Inference to the best explanation: A neglected approach to theory appraisal in psychology

BRIAN D. HAIG
University of Canterbury

Explanatory theories in psychology usually are evaluated by using the hypothetico-deductive method and testing them for their predictive adequacy. This article brings the alternative idea of inference to the best explanation to the attention of psychologists and suggests that it provides them with a set of methodological resources for evaluating the explanatory worth of their theories. I present 3 characterizations of the notion of inference to the best explanation. The strengths and limitations of inference to the best explanation are then considered, as is its relationship to the hypothetico-deductive and Bayesian approaches to theory appraisal. Thereafter, I suggest a proper scope for inference to the best explanation as a scientific method, make recommendations for using the approach in psychology, and recommend its adoption in the appraisal of psychological theories.

If the fact that a theory provides the best available explanation for some important phenomenon is not a justification for believing that the theory is at least approximately true, then it is hard to see how intellectual inquiry could proceed. —Richard Boyd (1984, p. 67)