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Knowledge as Objectively Justified Belief


According to Lehrer’s defeasibility account of knowledge, we can understand knowledge as undefeated justified true belief. But this account faces many serious problems. One important problem is that from one’s subjective point of view, one can hardly bridge the gap between one’s personal justification and objective truth. Another important problem is that this account can hardly accommodate the externalist intuition that the epistemic status of a belief is not entirely determined by factors that are internal to the subject’s perspective. The goal of this paper is to offer an alternative account of knowledge which can successfully deal with these problems. On the basis of a Sellarsian social practice theory of justification, I argue that we can understand knowledge as objectively justified belief.

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  1. 1.

    The deflationary views of truth include the redundancy theory, disquotationalism, minimalism, the prosentential theory, and the anaphoric theory. Each representative work is, respectively, as follows: Ramsey, 1927; Quine, 1970; Horwich, 1998; Grover et al., 1975; Brandom, 1994. It is beyond the scope of this paper to properly defend the deflationary conception of truth. For a more discussion of this conception of truth, see Lee 2017.

  2. 2.

    The concept of epistemic defeasibility was originally introduced by Roderick Chisholm (1964), based on an analogy with the ethical concept of a defeasible obligation. And the defeasibility account of knowledge is also defended by many philosophers, such as Lehrer and Paxson (1969), Klein (1980; 2008), Swain (1981; 1998), Pollock (1986), Hilpinen (1988), and De Almeida & Fett (2016).

  3. 3.

    Lehrer (2000, p. 13) distinguishes between belief and acceptance. Fortunately, this distinction would not affect the main arguments of this paper. Thus, for the sake of brevity, I will ignore this distinction in this paper.

  4. 4.

    De Almeida and Fett (2016) argue that the most important objections raised against the defeasibility account so far are the ones put forward by Feldman (2003), Foley (2012), and Turri (2012) and also that the defeasibility account can successfully tackle these objections. In this paper, I do not want to dispute that the defeasibility account could handle these objections. On my view, however, the defeasibility account is still vulnerable to the following problem: the fact that a subject has done everything to reach the truth from her subjective point of view is compatible with the possibility that her belief might be defeated by contrary evidence available in the future.

  5. 5.

    For a more detailed discussion and defense of this claim, see Lee 2017.

  6. 6.

    On my view, we can know that p, even if we cannot completely rule out the possibility that contrary evidence might be available in the future. In connection with this view, someone might wonder whether this view embraces the so-called abominable conjunctions (DeRose 1995, pp. 27–29). These are conjunctions of the following sort: “I know that I have hands, but I don’t know that I am not a handless brain in a vat,” and “I know that that animal is a zebra, but I don’t know that that animal is not a cleverly disguised mule.” Clearly, these conjunctive claims sound paradoxical or absurd. But my view does not embrace such an abominable conjunction. What should be noted in this regard is that the justification of a knowledge claim should be distinguished from the objective correctness of such a claim. We can justifiably claim that we know that p if we have adequate evidence for the proposition that p. Certainly, such a knowledge claim is fallible. In other words, we cannot rule out the possibility that such a knowledge claim might turn out to be false in the future. But fallibility is one thing, but falsity is another thing. If, on the one hand, such a knowledge claim is not based on any overriding error, it is an instance of knowledge. If, on the other hand, such a knowledge claim is based on an overriding error, it is not an instance of knowledge. Now, with this point in mind, consider whether my account of knowledge entails abominable conjunctions. On my account, I can make a fallible claim that I know that I have hands. In such a case, I can also make a fallible claim that I know that I am not a handless brain in a vat. And insofar as the former fallible claim, as a matter of fact, is not based on any overriding error, I know that I have hands. In such a case, I also know that I am not a handless brain in a vat. For this reason, on my account, if I know that I have hands, I also know that I am not a handless brain in a vat. But this view does not require me to deny that this knowledge claim is fallible. As has been emphasized, we can justifiably claim that we know that the earth is round while admitting that this knowledge claim is not infallible.

  7. 7.

    For a detailed discussion and defense of this point, see Lee 2017.

  8. 8.

    Here, let me address a question raised by an anonymous reviewer. Consider the possibility that a certain subject, say S, believes that the scientific name of watermelon is Citrullus lanatus, but she has lost all the memories related to how she got this belief. For the sake of brevity, let us call the content of this belief q. S in this case would not be able to meet the demand for justifying her belief that q, because she has no idea about how she got this belief. Nevertheless, someone else in her society could meet this demand for justification. If this is the case, the question is whether, on my account, S may count as knowing that q. The answer is “no.” On my account, the belief that the scientific name of the watermelon is Citrullus lanatus is not the kind of belief that has default justification in our social practice of justification. In other words, this is not a case in which the burden of proof shifts to any challenger. As a consequence, S is justified in believing that q only if she herself can meet the demand for justifying the belief. Here, I do not deny that S could meet such a demand by engaging in the social division of epistemic labor. For example, if she can justifiably claim that she learned the scientific name of the watermelon from a certain botanist, then she can be justified in believing that q. But S’s case under consideration is not such a case. Recall that she has lost all the memories related to the source of her belief. Accordingly, she is unable to provide any positive reason for her belief. Therefore, on my account, she should not count as knowing that q.

    Let me also address another question raised by an anonymous reviewer. The question is how my social practice theory of justification can be applied to the famous barn façade case introduced by Alvin Goldman (1976). In this case, Henry is driving through the countryside, and see a number of structures that appear to be barns. And by seeing one of them, he forms the belief that the object he sees is a barn. Unbeknownst to him, however, the district he has just entered is “Fake Barn County,” which is full of fake barns. These fake barns look just like real barns from the road, but they are mere barn facades. As it turns out, there is one real barn on the county, and Henry’s belief just happens to be about that one. On my account, Henry in this case cannot count as knowing that the object he sees is a real barn. The reason is clear. As mentioned before, one’s ordinary perceptual beliefs have default justification. Accordingly, Henry’s perceptual belief can have a default positive justificatory status unless it is successfully challenged with positive reasons. But an objector can provide such a positive reason against it. For example, she can point out to Henry that he is driving through Fake Barn County, and so his belief that the object he sees is a barn is very likely to be false. Insofar as Henry cannot meet this objection, his belief loses its default justificatory status. As a consequence, he is not justified in believing that the object he sees is a real barn.

  9. 9.

    There are some similarities between my account of knowledge and Michael Williams’s account (2001). But my account is also different from his account in many important respects. Owing to limitations of space, let me just mention three important differences. First, Williams (2001, p. 177) defends a partially externalist view that the justificatory status of a belief may depend on some non-doxastic contextual factor of which we are unaware. By contrast, my account is not an externalist view, because it denies that the epistemic status of a belief is determined in part by factors that are not accessible to any person. On my view, the epistemic status of a belief can be determined only by what is, at least in principle, ascertainable intersubjectively. Second, Williams (2001, p. 171) endorses what he calls “a pragmatic conception of epistemic norms,” according to which epistemic norms are fixed by us in light of our practical interests, projects, and assessment of our situation. By contrast, I uphold a coherentist justification of epistemic norms (see Lee, 2021). Third, Williams takes a contextualist approach to knowledge, according to which standards for claiming or attributing knowledge can vary depending on context. But I deny such a contextualist approach.


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Lee, B.D. Knowledge as Objectively Justified Belief. Acta Anal (2021).

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  • The defeasibility account of knowledge
  • The deflationary conception of truth
  • A Sellarsian coherence theory
  • Objective justification
  • Objective truth
  • Lehrer