Explanation in Neurobiology: an Interventionist Perspective

Issues about explanation in psychology and neurobiology have received a great deal of philosophical attention lately. To a significant degree this reflects the impact of discussions of mechanism and mechanistic explanation in recent philosophy of science. Several writers (hereafter mechanists), including perhaps most prominently, Carl Craver and David Kaplan (Craver 2000, 2006; Kaplan and Craver 2011, Kaplan 2011), have argued that at least in psychology and neuroscience, mechanistic theories or models are the predominant mode of explanation, with other sorts of theories or models often being merely “descriptive” or “phenomenological” rather than explanatory 2 . Other writers such as Chermero and Silberstein (2008) have disputed this, arguing that, e.g., dynamical systems models are not mechanistic but nonetheless explanatory. This literature raises a number of issues, which I propose to examine below. First, how should we understand the contrast between explanatory and descriptive or phenomenological models within the context of neuroscience? What qualifies a theory or model as “mechanistic” and are there reasons, connected to some (plausible) general account of explanation, for supposing that only mechanistic theories explain? Or do plausible general theories of explanation suggest that other theories besides mechanistic ones explain? In particular, what does a broadly interventionist account of causation and explanation suggest about this question? If there are plausible candidates for non-mechanistic forms of explanation in psychology or neurobiology, what might these look like? What should we think about the explanatory status of “higher level” psychological or neurobiological theories that abstract away from “lower level” physiological, neurobiological or molecular detail and are, at least in this respect, “non-mechanistic?” In what follows I will argue for the following conclusions. First, I will suggest that an interventionist framework like that developed in Woodward (2003) can be used to distinguish theories and models that are explanatory from those that are merely descriptive. This framework can also be used to characterize a notion of a mechanistic explanation, according to which mechanistic explanations are those that meet interventionist criteria for successful explanation and certain additional constraints as well. However, from an interventionist perspective, although mechanistic theories have a number of virtues, it is a mistake to think that mechanistic models are the exclusive or