The pragmatics of explanation

The pragmatic theory of explanation (Van Fraassen, 1988) proposes that background knowledge constrains the explanatory process. Although this is a reasonable hypothesis and research has shown the importance of background knowledge when evaluating explanations, there has been no empirical study of how the background constrains the generation of explanations. In our study, participants viewed one of two sets of preliminary movie clips of some novel items engaged in a series of actions and then all were asked to explain the same final clip. Between conditions, we varied whether the events in the preliminary clips completed a system. In the systematic condition, a greater proportion of functional explanations were generated for the final clip compared to the non-systematic condition. Interestingly, despite the difference in the types of explanations generated, the participants showed high agreement in the evaluation of explanations provided by the experimenters