Is Explanation the Foundation? (by guest blogger G. Randolph Mayes)
One of my main interests is explanation. I think there may be no other concept that philosophers lean on so heavily, yet understand so poorly. Here are some examples of how critical the concept of explanation has become to contemporary philosophical debates.
1. A popular defense of scientific realism is that the existence of theoretical entities provides the best explanation of the success of the scientific enterprise.
2. A popular view concerning the nature of inductive rationality is that it rests on an inference to the best explanation.
3. A popular argument for the for the existence of other minds is that other minds provide the best explanation of the behavior of other bodies.
4. A popular argument for the existence of God is that a divine intelligence is the best explanation of the observed order in the universe.
This is a short list. The concept of explanation has been invoked in similar ways to analyze the nature of knowledge, theories, reduction, belief revision, and abstract entities. Interestingly, few of the very smart people who defend these views tell us what explanation is. The reason is simple: we don’t really know. The dirty secret is that explanation is just no better understood than any of the things that explanation is invoked to explain. In fact, it is actually worse than that. If you spend some time studying the many different theories of explanation that have been developed during the last 60 years or so, you’ll find that most of them give little explicit support to these arguments.
The reason for this is worth knowing. Most philosophical theories of explanation have been developed in an attempt to identify the essential features of a good scientific explanation. The good-making features of explanation were generally agreed to be those that would account for how explanation produces (and expresses) scientific understanding. There are many different views about this, but an assumption common to most of them is that a good scientific explanation must be based on true theories and observations. That sounds pretty reasonable, but here’s the rub: If truth is a necessary condition of explanatory goodness, then it makes no sense at all to claim that a theory’s explanatory goodness is our basis for thinking it is true.
All of the arguments noted above do just this, invoking a principle commonly known as “inference to the best explanation” (IBE, aka ‘abduction’). This idea, first articulated by Charles Peirce, has been the hope of philosophy ever since W.V.O. Quine pounded the last nail into the coffin of classical empiricism. This latter tradition had sought in vain to demonstrate that inductive rationality could ultimately be reduced to logic. For many, IBE is a principle that, while not purely logical, might serve as a new ‘naturalized’ foundation of inductive rationality.
Bas van Fraassen, the great neo-positivist, has blown the whistle on IBE most loudly, arguing that it is actually irrational. One of his criticisms is quite simple: It is literally impossible to infer the best explanation; all we can infer is the best explanation we have come up with so far. It may just be the best of a bad lot.
One way to understand the disconnect between traditional theories of explanation and IBE is to note that there are two fundamentally different ways of thinking about explanation. In one, basically transactional sense, explanations are the sorts of things we seek from pre-existing reserves of expert knowledge. When we ask scientists why the night sky is dark or why it feels good to scratch an itch, we typically accept as true whatever empirical claims they make in answering our question. Our sense of the quality of the explanation is limited to how well we think this information has answered the question we’ve posed. This, I think, is the model implicit in most traditional theories of explanation. The aim is to show in what sense, beyond the mere truth of the claims, that science can be said to provide the best answers.
In my view, IBE has more to do with a second sense of explanation, belonging to the context of discovery rather than communication of expert knowledge. In this sense, explaining is a creative process of hypothesis formation in response to novel or otherwise surprising information. It can occur within a single individual, or within a group, but in either case it occurs because of the absence of authoritative answers. It is in this sense of the term that it can make sense to adopt a claim on the basis of its explanatory power.
Interestingly, much of the work done on transactional accounts of explanation is highly relevant to the discovery sense of the term. Many of the salient features of good explanations are the same in both, notably: increased predictive power, simplicity, and consilience. (This point is made especially clearly in the work of philosophically trained cognitive psychologists like Tania Lombrozo.) What is not at all clear, however, is that any of the IBE arguments noted above will have the intended impact when the relevant sense of explanation belongs more to what Reichenbach called “the context of discovery” rather than the “context of justification.”