Contra-exemplos

"The following kind of scenario is familiar throughout analytic philosophy. A bold philosopher proposes that all Fs are Gs. Another philosopher proposes a particular case that is, intuitively, an F but not a G. If intuition is right, then the bold philosopher is mistaken. Alternatively, if the bold philosopher is right, then intuition is mistaken, and we have learned something from philosophy. Can this alternative ever be realised, and if so, is there a way to tell when it is? In this paper, I will argue that the answer to the first question is yes, and that recognising the right answer to the second question should lead to a change in some of our philosophical practices.

The problem is pressing because there is no agreement across the sub-disciplines of philosophy about what to do when theory and intuition clash. In epistemology, particularly in the theory of knowledge, and in parts of metaphysics, particularly in the theory of causation, it is almost universally assumed that intuition trumps theory. [...] I claim that it is (usually) the epistemologists and the metaphysicians who are wrong. In more cases than we usually imagine, a good philosophical theory can teach us that our intuitions are mistaken. Indeed, I think it is possible (although perhaps not likely) that the justified true belief (hereafter, JTB) theory of knowledge is so plausible that we should hold onto it in preference to keeping our intuition that Gettier cases are not cases of knowledge.

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In short, the true theory of knowledge is the one that does best at (a) accounting for as many as possible of our intuitions about knowledge while (b) remaining systematic. A ‘theory’ that simply lists our intuitions is no theory at all, so condition (b) is vital. [...] counterexamples to a theory count against it. While a theory can be reformist, it cannot be revolutionary. A theory that disagreed with virtually all intuitions about possible cases is, for that reason, false. The theory: X knows that p iff X exists and p is true is systematic, but hardly plausible. As a corollary, while intuitions about any particular possible case can be mistaken, not too many of them could be. Counterexamples are problematic for a theory, the fewer reforms needed the better, it’s just not that they are not fatal. Importantly, not all counterexamples are as damaging to a theory as others. Intuitions come in various degrees of strength, and theories that violate weaker intuitions are not as badly off as those that violate stronger intuitions. Many people accept that the more obscure or fantastic a counterexample is, the less damaging it is to a theory." - Brian Weatherson, What good are counterexamples (2003)