I would characterize every discipline that aims at investigating some subject matter as desiring to produce an explanation of that subject matter, to categorize it and devise rules that describe its internal structure and its relations to other things, as well as how it changes over time. Obviously what we are studying and how we study it varies from discipline to discipline, and thus the nature of the explanations produced will vary, but anything that can be said about explanations in general applies to all the disciplines involved in producing them. If there is some best way to arrive at explanations it must apply to all these disciplines, and if certain kinds of explanations are invalid they are invalid no matter where they are invoked. I bring this up simply because the examples I will be providing will primarily be concerned with philosophical explanations, since those are the kinds of explanations I am most familiar with, but unless philosophers are extraordinarily unlucky I expect that the kinds of examples I am using here could easily be replaced with developments in the history of physics or economics.
With that said allow me to proceed to my central claim, which is that when we search for explanations we generally begin our search with expectations about the form that the explanation can take. And while sometimes these expectations may be useful, in steering us directly towards the best explanations, at other times they can completely prevent us from successfully explaining what we intend to. Such tendencies result in the kinds of explanations that simply add more epicycles rather than approaching the problem in new ways. And in the history of astronomy the Copernican revolution is an example of breaking away from flawed expectations about the form that explanations can take in order to arrive at better ones. Before Copernicus the job of astronomy was to explain how the planets revolved around the earth. And obviously if you are trying to develop such an explanation the idea that the planets might revolve around the sun will never even enter your mind, that the planets orbit the earth is a kind of assumption which you proceed to cast your explanations in terms of. The Copernican revolution can thus be understood as shifting what needed to be explained from the orbit of the planets around the earth to observed planetary motion. And when trying to explain how the planets are observed to move we are no longer required to make them follow paths around the earth. Now this is not to say that before Copernicus any astronomer ever sat down and decided that the earth being at the center was something that they were going to take for granted, they took it for granted without realizing that the assumption was not necessarily true. And that is what makes such expectations so insidious, because they lead us to effectively reject whole categories of possible explanations without actually seriously considering them.
Given that our expectations with respect to what kinds of explanations are acceptable can be problematic we would like to know when these expectations are actually interfering with our theorizing. Unfortunately, by their very nature, they are essentially unconscious, meaning in this case just that we don’t think about them as assumptions, we operate on the basis of them without passing judgment on them. But there are some indirect clues that we can pick up that can at least awaken us to the possibility that such expectations might be interfering with our judgment, even if they won’t point them out directly. One such clue is when we find ourselves dealing with problems that seem insoluble, by which I mean not that we are having problems solving them, because any truly interesting problems are hard to solve, but when we find ourselves facing problems that have resisted solution for a significant amount of time. With such a problem it might very well be the case that it has resisted solution for so long because those investigating it, us included, have shared some common assumption about what the explanation should be that has prevented us from arriving at an actually satisfying explanation. Another sign that we may be suffering from illegitimate expectations about the form the explanation should take is when the explanations that seem best all raise further problems which themselves have no obvious solution. Consider, for example, the desire to know why the universe exists. Since the explanations of why things exist are often causal explanations some may insist that to answer that question we must reveal the cause of the universe to them. But to give an explanation in such terms leads to an infinite regress, because if everything must have a causal reason for its existence so to must whatever we posit as the cause of the universe. Thus the explanation simply raises more things that must be explained. Or consider the proposal that mathematical entities, such as numbers, are objects. Such a proposal solves certain problems, but it raises the problem of how we have access to these objects. And if some special mental faculty is supposed we must then ask how that faculty manages to provide us with reliable information (since all such information supervenes on causal relations), and so on. Such explanations prove equally unsatisfactory because they simply move around what needs to be explained (rather than, for example, explaining it in terms of things that have already been satisfactorily explained). Again, such an explanation is not really an explanation, but rather a sleight of hand, which pretends to be an explanation simply by kicking up dust and so hiding what is in need of an explanation. When we find ourselves dealing with explanations that hide the problem rather than solving it this is an indication that there is something preventing people from legitimately solving it, quite possibly poor expectations about the explanation itself.
Suppose then that we become convinced that certain expectations are preventing us from formulating satisfactory explanations, or that we suspect they might be. To help discover what these expectations might be it is helpful to consider where they often stem from. One source of these expectations is simply the assumption that what worked for similar cases in the past will work for the case we are confronted with now. For example, scientists were baffled by certain phenomena in the early 20th century because they couldn’t explain them in terms of Newton’s laws. Such mistakes are, however, the most innocent (because that is essentially how we should proceed), and thus often the easiest to overcome. The more problematic assumptions stem, I think, from the way we talk about phenomena, and thus, I suppose, the way we naturally find ourselves thinking about them. For example, we often find ourselves talking about phenomena of all kinds as things, because that is simply the way language works, the most natural way to talk about something is to label it with a noun so as to talk about that thing. This leads to questions such as “what kind of thing are numbers?” which, as mentioned above, simply can’t satisfactorily be answered because numbers are not things. But, thinking about them as things, may lead some to believe that we need to find them or, like other things, their failure to exist will imply that they are fictions and thus completely subjective. Without the expectation that numbers are things there is no reason to be led to such conclusions. Another way to develop faulty expectations is simply to assume that our linguistic judgment is the ultimate and best way to judge things in a certain situation. For example, it is a faulty expectation to demand that whatever our explanation of goodness says is good will be intuitively judged to be good by us. And, finally, our language may mislead us about what needs to be explained, because if we develop a label to describe some phenomena we may think that this label itself needs explanation. But it is quite possible that the correct explanation may simply reveal that we have incorrect expectations about this label and what it signifies, such that in many ways it might be considered an illusion. The best example of this is the demands of some that we explain qualia (what things “feel” like), and that these explanations somehow expose the qualia themselves to us. But it is quite possible for the correct explanation in this case to be an explanation of why we think about our own consciousness in such a way that there are qualia. To insist that qualia really are something of their own is to presuppose something about the form of our explanation, when all we are really required to explain is our judgments about qualia.
Let us further suppose then that by means of such considerations we have isolated certain flawed expectations that are preventing us from providing satisfactory explanations, and indeed I have identified quite a few candidates already where our expectations might really be interfering. How do we overcome these expectations? The best way may simply be to provide a better explanation that doesn’t conform to them, and then hope that the clear superiority of this explanation will reveal the expectations themselves as flawed. This is the way the physical sciences tend to proceed, and they are bothered least by faulty expectations. But the rest of us may not be so lucky, and may have to supplement our explanation with reasons to reject the expectations themselves. And one way to go about doing that is to illustrate how the expectations arise and then argue that such sources can have no claim to legitimacy (usually this is easiest to do when the root of the expectations is linguistic). The problem is, unfortunately, that not everyone will be convinced by such arguments. In philosophy, for example, intuitions are very heavily leaned upon (although they are often obscured in some way so that those leaning on them can claim that they are not intuitions). And these expectations are problematic precisely because they are intuitive, and so an explanation that goes against them will be unintuitive by necessity. My solution is simply to reject doing philosophy on the basis of intuition of any kind, and thus if someone should complain that we have said something unintuitive we can simply shrug our shoulders and move on, because we simply can’t satisfy everyone’s intuitions.
But the best solution to all of these problems is to avoid them from the outset by describing the problems we are trying to solve, so that the possibility that significant expectations may slip in is reduced or eliminated. Which means that the way in which we describe our problems must be free from any presuppositions about the form the solution may take or things it must involve. The simplest way to do that is to phrase our problems only in terms of what we can observe, at least as much as we can (with the idea that whatever we cast our problem in terms of that isn’t a matter of observation may turn out to be problematic). If we are trying to explain why certain lights in the night sky move as they do then this presupposes nothing about them or our explanation. They may be planets moving around the earth, or around the sun, or they may simply be persistent delusions. And when we can’t cast a problem in such terms it reveals that we are including something problematic in it, something that we must question the legitimacy of.