Reliabilist definitions of knowledge tend to go something like this:
R: "S knows that P iff S has a true belief in P that was generated by a generally reliable belief-forming mechanism."*
A traditional objection to this is the so-called "generality problem," which goes something like this:
I want to know what time it is, so I pull my cell phone out of my pocket, flip it open and look at the screen. Now, assuming that my phone is working properly, I now have a true belief about what time it is**, etc., we'd want to call my belief about what time it is a case of knowledge, and the reliabilist would point to the process by which I arrived at that belief--checking my phone--as a generally reliable one.
But wait! What level of generality are we talking about? The process of *me* checking *this particular* phone? The process of anyone checking the time on any phone? The process of anyone checking the time on any time-telling device? Depending on what level we're talking about, the statistical (hypothetical limiting) frequency with which the process in question generates true beliefs will vary all over the damned place. Moreover, there seems to be no non-ad hoc way to decide which level is the important one. Ergo, reliabilism is just a hopeless epistemic theory.
Hold that thought for a moment while we switch our attention to evolutionary biology. Whatever one thinks of generation by "generally reliable belief-forming processes" as a condition that makes true belief knowledge, no reasonable person would deny that the claim that "natural selection" is the primary engine of evolution is a respectable, informative, and well-understood bit of biological theory, or indeed that it's extraordinarily well-confirmed by the evidence. Right?
Jerry Fodor has recently attacked natural selection, claiming that, when it comes to pairs of correlated traits, (a) there's no fact of the matter about which trait is "selected for" and which is the free-riding spandrel, or at least that (b) there's no way for us to have epistemic access to which is which, and at any rate that (c) standard evolutionary biology's problems with sorting out which trait is which in a plausible, principled way, whatever exactly the standard for plausibility and principledness is taken to be in this context (which is far from obvious) constitute a huge problem for the theory of evolution by natural selection, indeed a reason to reject theory. (Many of Fodor's formulations--e.g. that the distinction between selected-for traits and spandrels is "invisible to natural selection"--are frustratingly hard to pin down, but fortunately, the distinction between the more radical reading of Fodor in (a) and the more moderate reading (b) isn't central to the point at hand. For our purposes, (c) is what really matters.) This may cause some head-scratching in readers who know enough contemporary biological theory to know something about how biologists investigate and sort out spandrels from selection.
In a review of Fodor's book by Ned Block and Philip Kitcher, they put the issue like this:
"Consider the famous case of industrially induced melanism in the peppered moth. Supposedly, in landscapes where pollution has destroyed the lichens on the trunks of trees, melanic (black) variants of the moth are better camouflaged when they rest on tree trunks than their lighter, speckled relatives. With improved camouflage, birds and other predators are less likely to pick the moths off the tree trunks. In polluted environments, then, melanic moths are more likely to survive, and hence to leave descendants in later generations. So far, so familiar.
"Enter Gould and Lewontin. Maybe moth coloration is a spandrel, and some other property of the moths is both relevant to their proliferation and correlated with their color. For example, evolutionary biologists have observed that moths usually rest by day on the undersides of branches rather than on the trunks of trees. So is the familiar black-as-camouflage story really true? Perhaps a characteristic of the larvae of melanic moths makes them more likely to survive. Or perhaps melanic moths have a tendency to move around less at night, which makes them less vulnerable to being eaten by bats (who care nothing for color). These are interesting alternatives to the familiar story, and the causal hypotheses they introduce can be tested in obvious ways: by examining the rates of larvae survival or by investigating nocturnal motions of moths. And this is what biologists have done. Concerned that an apparent adaptation (a camouflaging color) may be a side effect, they have looked for correlated traits that might figure in some alternative process that would culminate in greater representation of the melanic moths. Despite some controversy in the 1990s, the traditional story seems to be standing up well.
"If Fodor and [his co-author] Piattelli-Palmarini acknowledge the evidence that favors the camouflaging-color hypothesis over the moth-larvae and moth-mobility hypotheses, they will have to say that the biologists have not been imaginative enough—that they have overlooked some other correlated trait for which there could be no fact of the matter about whether it, or the black coloration, caused the reproductive success.
"What exactly could this trait be? One possibility, suggested by remarks in some of Fodor’s previous writings, would be that there are two different properties: being black, on the one hand, and matching the environment on the other. Is there a fact of the matter as to which of these causes the reproductive success?....
...[Fodor and Piattelli-Palmarini] envisage a vast space of properties and expect proponents of natural selection to discriminate among all the rivals. Not only is there a property of being-a-melanic-moth, there is also a property of being-a-melanic-moth-and-smaller-than-Manhattan."
Now, I'm not particularly interested in the Fodor-exegesis question here. Perhaps Block and Kitcher have captured Fodor's position and perhaps they haven't. However, in terms of Fodor as Block and Kitcher understand him, two points seem worth making here:
(1) This doesn't seem to be a particularly good objection to standard biological theory,
(2) It's strikingly similar to the generality problem for reliabilism.
In fact, it seems reasonable to call Fodor's-objection-interpreted-this-way a sort of generality problem for biology, where instead of worrying about how to cut up reliable processes, we're worrying about how to cut up causally-efficacious traits.
So, if we don't take the difficulty in determining whether being-a-black-moth or being-a-black-moth-smaller-than-Manhattan or being-a-moth-smaller-than-Manhattan-that-blends-into-the-color-of-its-background is relevant level of analysis for natural-selection-talk to be much of a problem for evolutionary biology, should we regard the difficulty in determining whether me-consulting-my-cell-phone, me-consulting-any-cell-phone or anyone-consulting-any-time-telling-device is the right level of analysis for reliable-process-talk to be a serious problem for reliabilism? Alternately, should we regard the fact that, for the sake of argument, the latter is clearly a troubling problem to be a good reason to take the generality worry about evolutionary biology seriously? Or are the two cases just so clearly and importantly disanalogous that our reaction to the generality problem for biology and our reaction to the generality problem in epistemology should properly be utterly independent of one another?
These questions aren't rhetorical. I'm open to the possibility that the generality problem really is a deep problem for reliabilism, although its biological analogue is an easily-dismissed problem for natural selection. The only positive claim I'm making here is a relatively narrow, wussy sort of claim:
There's an interesting, suggestive analogy between the two cases, and if one shares my strong intuition that the generality problem for evolutionary biology is a non-problem, this should, at the very least, give us a good reason to pause and take a harder look at the generality problem for reliabilism, and why exactly we take it to be such a problem.
*A note of caution here: Not everyone whose epistemic views would be characterized as reliabilist would put it quite like that, some would add substantial extra conditions and some epistemologists, while emphasizing reliability considerations enough to deserve the "reliabilist" label, might regard the project of trying to precisely formulate necessary and sufficient conditions for knowledge as a fool's errand. For present purposes, though, R should be good enough to capture the aspect of the position I'm interested in.
**"Etc." here papers over, among other things, Gettier-style problems....what do we say about a case where my phone somehow froze exactly twenty four hours ago and I didn't notice? Is that a reliably-caused true belief? This is an interesting question, but it's one that I suspect many people likely to read this are beyond sick of hearing about, and one which I don't have much of anything new to say about in any case.