Models, Conceptual and Predictive: A Response to Johnson's Models-as-Fables

James Johnson argues that formal models are best conceived as fables which provide lessons about empirical phenomena and the standard rationale of testing model predictions fails. Without justifying the standard rationale as such, we argue that models produce scientific predictions. These predictions come at different levels or granularity of description and in different forms each bearing some degree of uncertainty, but still give conditions for the existence of political phenomena. Models and their predictions require projection onto the world, and that projection involves interpretation. Tests utilize inference to the best explanation, and it is the conceptual or theoretical aspect of models that make them explanatory. We discuss the extent to which our characterisation of models and their explanatory form versus that of Johnson constitutes a verbal or substantive dispute.