An Argument Against Skepticism
The skeptic claims that we are wrong to credit ourselves with knowledge. Our belief that we possess knowledge is a false belief: we make an error when we ascribe knowledge to ourselves. But why do we make this error? On this question the skeptic is strangely silent: we are not told what the source of the error is and why we fall into it. This is unsatisfactory: surely an error this large, this persistent, should have an explanation. The skeptic owes us a theory of the error he imputes. The error that the earth is stationary lasted for millennia and was difficult to dislodge, but it is an understandable error, given our location and the facts of physics (inertia etc.). Not for no reason did people cling to the error in question. Similarly for the error (if it is one) that objects are objectively colored, which was not detected until the seventeenth century (initially by Galileo). This error can be seen to arise from the way objects look: they look objectively colored. In general errors have explanations; they are not gratuitous, groundless, inexplicable. If we cannot explain the error, the claim that it is an error is pro tanto dubious, especially if the claim of error rests on convoluted argument. So, the skeptic needs to meet this challenge or else concede weakness in his position; at the very least the question should be acknowledged and addressed. Why do we falsely believe that we have knowledge if the skeptic is right in saying that we demonstrably do not? The arguments for skepticism are not complex and can be easily grasped, so why have they not undermined the belief in knowledge long ago? Why do we even have the concept of knowledge if the concept is never (or seldom) instantiated? Is it perhaps that the skeptic is wrong and we do have knowledge in the cases where we believe we do?
Here is a possible explanation: we are under the illusion that we have knowledge. There are well known visual illusions that produce false beliefs, and we can envisage more pervasive types of visual illusion (such as the illusion that objects are objectively colored). But this is not a plausible explanation: for we don’t perceive instances of knowledge by means of the senses. It isn’t as if it looks as if knowledge exists but it really doesn’t (like the proverbial pink rats). We don’t perceive knowledge at all, so there can’t be sensory illusions of knowledge. Nor is it plausible that the word “knowledge” encourages the error: we don’t believe we have knowledge because the word intimates that we do; it isn’t that the word is a very vivid name that conjures up a non-existent referent. So, it is a mystery why we commit and persist in the error, finding ourselves shocked when the skeptic mounts his assault. And the skeptic never concludes his assault by saying, “And the reason you commit the error I have just exposed is X”, where “X” stands for the error theory we are searching for. Moreover, we don’t typically respond to the skeptic’s argument by saying immediately, “Oh silly me, how could I have made this error for so long?”. On the contrary, the alleged error is remarkably resistant to revision (as Hume pointed out); we don’t simply abandon the belief in knowledge forthwith. In other cases of error, even ancient and universal error, reason prevails and the error is corrected; but skepticism has made little progress in removing the erroneous beliefs it attacks, though it has been around for over 2,000 years. We just don’t respond to it as one whose error has been convincingly exposed. What is the skeptic’s explanation of this resistance—if not that there is really no error that is being exposed? It’s surely not simple dogmatism and arrogance—epistemic overestimation—since it really does seem to us that we know things about the world. We sincerely believe that we have genuine knowledge of things; it’s not that we only act this way in order to impress others. That is why skepticism comes as a shock to the system.
Note that this point doesn’t tell us what is wrong with the skeptic’s arguments; it merely suggests that something must be wrong. The next task would be to identify precisely what that something is. But it does indicate what is peculiar about skeptical doubt, namely that it is removed from ordinary sources of error. In the normal course of things, we experience no difficulty in recognizing error, explaining it, and revising our beliefs accordingly. For example, we might come to see that we were subject to a visual illusion that gave rise to a false belief, so that we were wrong to think that we had knowledge. It is well within our powers to change our attributions of knowledge to ourselves. Here there is no problem with supplying an error theory and changing our epistemic beliefs because of it. But what explains my erroneous belief that I know there is an external world? It isn’t that I have recently discovered that I am a brain in a vat—that would certainly explain my false belief that I know there is an external world! But the problem is that there is no such explanation of why I erroneously believe that I know there is an external world, even if there is. Maybe I don’t know this, as the skeptic argues, but why do I believe that I know it to begin with? Why didn’t I recognize before that my belief that I know is shaky or baseless? Why did it take the skeptic to make me aware of this? What if skepticism had never been invented so that no one ever questioned their general beliefs about things (the external world, the past, other minds)? What would explain such massive error, on the assumption that I simply don’t know such things? Why do human beings so confidently believe that they have knowledge when they don’t? The error seems utterly inexplicable (if error it is). Isn’t it more likely that there is no error and we really do know? False astronomical beliefs are easy to explain, or false biological beliefs, but false epistemic beliefs are not like this—why are we wrong in our beliefs about what we know? To put it differently, why are we so wrong about which of our beliefs are justified? Maybe we are wrong, but we need to be told why we would make such a basic mistake. Are we just stupid? But lots of very smart people think we have knowledge, so it can’t be a matter of low IQ. Is it that we have such beliefs by instinct and don’t question them? Is the explanation that we are programmed genetically to believe we have knowledge? But what reason is there to believe that, and why can’t we rationally question such an instinct once reason gains a foothold in our minds? Nor is the belief instilled in us by something akin to religious indoctrination. None of the standard explanations for error works, so the skeptic has an undischarged obligation. We are guilty of a conceptual error, according to the skeptic, but what explains this error has yet to be diagnosed.
 A similar challenge is faced by the opponent of free will: if there is no free will, why do people think there is? But here there are viable options: people might be confusing genuine freedom with mere freedom from coercion, or there might be a phenomenology of freedom that coexists with actual determinism. In the case of skepticism, however, nothing suggests itself, so the skeptic is left with an unexplained error, and one that cries out for explanation. Not that skepticism lacks intuitive force and powerful arguments in its favor, but it also faces intuitive and powerful counterarguments. I am just adding a further consideration into the mix, not trying to resolve the issue one way or the other.