Is knowledge justified true belief?

Is knowledge justified true belief? Most philosophers believe that the answer is clearly ‘no’, as demonstrated by Gettier cases. But Gettier cases don’t obviously refute the traditional view that knowledge is justified true belief (JTB). There are ways of resisting Gettier cases, at least one of which is partly successful. Nevertheless, when properly understood, Gettier cases point to a flaw in JTB, though it takes some work to appreciate just what it is. The nature of the flaw helps us better understand the nature of knowledge and epistemic justification. I propose a crucial improvement to the traditional view, relying on an intuitive and independently plausible metaphysical distinction pertaining to the manifestation of intellectual powers, which supplements the traditional components of justification, truth and belief.     

A Peircean examination of Gettier’s two cases

If we accept certain Peircean commitments, Gettier’s two cases are not cases of justified true belief because the beliefs are not true. On the Peircean view, propositions are sign substitutes, or “representamens.” In typical cases of thought about the world, propositions represent facts. In each of Gettier’s examples, we have a case in which a person S believes some proposition p, there is some fact F* such that were p to represent F* to S then p would be true, and yet p does not represent F* to S but some other fact F of which p is false. Since truth is a property of propositions with respect to their representational function, it follows that the belief is not true. Although an examination of Gettier’s two cases, this essay is not a defense of the justified true belief (JTB) analysis of knowledge, for there are objections to the JTB analysis other than Gettier’s two cases. Rather, Gettier’s two cases are of particular interest for the light they shed on the nature of truth and representation.

     

Getting ‘Lucky’ with Gettier

Abstract: In this paper I add credence to Linda Zagzebski's (1994) diagnosis of Gettier problems (and the current trend to abandon the standard analysis) by analyzing the nature of luck. It is widely accepted that the lesson to be learned from Gettier problems is that knowledge is incompatible with luck or at least a certain species thereof. As such, understanding the nature of luck is central to understanding the Gettier problem. Thanks by and large to Duncan Pritchard's seminal work, Epistemic Luck, a great deal of literature has been developed recently concerning the nature of luck and anti‐luck epistemology. The literature, however, has yet to explore the very intuitive idea that luck comes in degrees. I propose that once luck is recognized to admit degrees even the slightest non‐zero degree (of the relevant sort) precludes knowledge. Connecting this to Zagzebski's thesis, I propose that a given theory of warrant must guarantee truth in order to avoid Gettier counterexamples (or subsequently deny that warrant bears any relationship to the truth whatsoever), simply because a sufficient standard analysis of knowledge cannot allow for knowledge that is even marginally lucky.     

Counter-Closure

The focus of this paper is the prima facie plausible view, expressed by the principle of Counter-Closure, that knowledge-yielding competent deductive inference must issue from known premises. I construct a case that arguably falsifies this principle and consider five available lines of response that might help retain Counter-Closure. I argue that three are problematic. Of the two remaining lines of response, the first relies on non-universal intuitions and forces one to view the case I construct as exhibiting a justified, true belief to which none of the usual diagnoses of knowledge failure in Gettier cases apply. The second line involves claiming that Fake Barns and its ilk are misdiagnosed by epistemological orthodoxy as Gettier cases. We are thus confronted by a trilemma: either the case I discuss undermines the first-blush plausible principle of Counter-Closure; or the case I discuss instantiates a novel kind of Gettier case; or a popular conception of a key range of alleged Gettier cases must be rejected. No matter which horn we choose, the case points to a philosophically curious conclusion.     

Warrant <Emphasis Type="Italic">does</Emphasis> entail truth

Let ‘warrant’ denote whatever precisely it is that makes the difference between knowledge and mere true belief. A current debate in epistemology asks whether warrant entails truth, i.e., whether (Infallibilism) S’s belief that p is warranted only if p is true. The arguments for infallibilism have come under considerable and, as of yet, unanswered objections. In this paper, I will defend infallibilism. In Part I, I advance a new argument for infallibilism; the basic outline is as follows. Suppose fallibilism is true. An implication of fallibilism is that the property that makes the difference between knowledge and mere belief (which I dub ‘warrant*’) is the conjunctive property being warranted and true. I show that this implication of fallibilism conflicts with an uncontroversial thesis we have learned from reflection on Gettier cases: that nonaccidental truth is a constituent of warrant*. It follows that infallibilism is true. In the second part of the paper, I present and criticize a new argument against infallibilism. The argument states that there are plausible cases where, intuitively, the only thing that is keeping a belief from counting as knowledge is the falsity of that belief. Furthermore, it is plausible that such a belief is warranted and false. So, the argument goes, infallibilism is false. I show that this argument fails.     

The cognitive act and the first-person perspective: an epistemology for constructive type theory

The notion of cognitive act is of importance for an epistemology that is apt for constructive type theory, and for epistemology in general. Instead of taking knowledge attributions as the primary use of the verb ‘to know’ that needs to be given an account of, and understanding a first-person knowledge claim as a special case of knowledge attribution, the account of knowledge that is given here understands first-person knowledge claims as the primary use of the verb ‘to know’. This means that a cognitive act is an act that counts as cognitive from a first-person point of view. The method of linguistic phenomenology is used to explain or elucidate our epistemic notions. One of the advantages of the theory is that an answer can be given to some of the problems in modern epistemology, such as the Gettier problem.     

Prospects for Epistemic Compatibilism

This paper argues that Sosa’s virtue perspectivism fails to combine satisfactorily internalist and externalist features in a single theory. Internalism and externalism are reconciled at the price of creating a Gettier problem at the level of “reflective” or second-order knowledge. The general lesson to be learned from the critique of virtue perspectivism is that internalism and externalism cannot be combined by bifurcating justification and knowledge into an object-level and a meta-level and assigning externalism and internalism to different levels.     

Bootstrapping and Content Parts

Christensen [Philosophy of Science, 50: 471–481, 1983] and [Philosophy of Science, 57: 644–662, 1990] provides two sets of counter-examples to the versions of bootstrap confirmation for standard first-order languages presented in Glymour [Theory and Evidence, Princeton University Press, Princeton, 1980] and [Philosophy of Science, 50: 626–629, 1983]. This paper responds to the counter-examples of Christensen [Philosophy of Science, 50: 471–481, 1983] by utilizing a new notion of content introduced in Gemes [Journal of Philosophical Logic, 26, 449–476, 1997]. It is claimed that this response is better motivated and more effective than that presented in Glymour [Philosophy of Science, 50: 626–629, 1983]. It is then argued that while this response meets some of the counter-examples of Christensen [Philosophy of Science, 57: 644–662, 1990] two of those counter-examples, though not unanswerable, suggest the need for a substantial reformulation of the formal versions of bootstrapping. The essay proceeds with such a reformulation, arguing that this new formulation better fits the philosophical insights that originally motivated bootstrapping than do Glymour’s earlier formulations. In the concluding sections some alternative solutions to the problem posed by the Christensen counter-examples are discussed.     

The folk conception of knowledge

How do people decide which claims should be considered mere beliefs and which count as knowledge? Although little is known about how people attribute knowledge to others, philosophical debate about the nature of knowledge may provide a starting point. Traditionally, a belief that is both true and justified was thought to constitute knowledge. However, philosophers now agree that this account is inadequate, due largely to a class of counterexamples (termed “Gettier cases”) in which a person’s justified belief is true, but only due to luck. We report four experiments examining the effect of truth, justification, and “Gettiering” on people’s knowledge attributions. These experiments show that: (1) people attribute knowledge to others only when their beliefs are both true and justified; (2) in contrast to contemporary philosophers, people also attribute knowledge to others in Gettier situations; and (3) knowledge is not attributed in one class of Gettier cases, but only because the agent’s belief is based on “apparent” evidence. These findings suggest that the lay concept of knowledge is roughly consistent with the traditional account of knowledge as justified true belief, and also point to a major difference between the epistemic intuitions of laypeople and those of philosophers.     

‘Unlucky’ Gettier Cases

This article argues that justified true beliefs in Gettier cases often are not true due to luck. I offer two ‘unlucky’ Gettier cases, and it's easy enough to generate more. Hence even attaching a broad ‘anti‐luck’ codicil to the tripartite account of knowledge leaves the Gettier problem intact. Also, two related questions are addressed. First, if epistemic luck isn't distinctive of Gettier cases, what is? Second, what do Gettier cases reveal about knowledge?     

Truthmaker Theory Does Not Solve The Gettier Problem

Truthmaker theory has become immensely popular in recent years. So, it is not surprising that we are beginning to see it put to work in other areas of philosophy. Recently, several philosophers have proposed that truthmaker theory is the key to solving the Gettier problem. Edmund Gettier demonstrated that the traditional analysis of knowledge (as justified, true belief) was unsatisfactory. The truthmaker solution proposes that knowledge is a justified, true belief, where the source of one's justification is either identical to, or else causally related to, the state of affairs which makes the believed proposition true. This amendment of the traditional analysis of knowledge purportedly escapes the problems identified by Gettier cases. In this paper, I will examine two particular recent endorsements of this solution – those from Sven Bernecker and Adrian Heathcote – and argue that truthmaker theory is not the key to solving the Gettier problem.     

Verisimilitude and Content

Popper’s original definition of verisimilitude in terms of comparisons of truth content and falsity content has known counter-examples. More complicated approaches have met with mixed success. This paper uses a new account of logical content to develop a definition of verisimilitude that is close to Popper’s original account. It is claimed that Popper’s mistake was to couch his account of truth and falsity content in terms of true and false consequences. Comparison to a similar approach by Schurz and Wiengartner show certain advantages of this new approach.     

Expert or Esoteric? Philosophers Attribute Knowledge Differently Than All Other Academics

Academics across widely ranging disciplines all pursue knowledge, but they do so using vastly different methods. Do these academics therefore also have different ideas about when someone possesses knowledge? Recent experimental findings suggest that intuitions about when individuals have knowledge may vary across groups; in particular, the concept of knowledge espoused by the discipline of philosophy may not align with the concept held by laypeople. Across two studies, we investigate the concept of knowledge held by academics across seven disciplines (N = 1,581) and compare these judgments to those of philosophers (N = 204) and laypeople (N = 336). We find that academics and laypeople share a similar concept of knowledge, while philosophers have a substantially different concept. These experiments show that (a) in contrast to philosophers, other academics and laypeople attribute knowledge to others in some “Gettier” situations; (b) academics and laypeople are much less likely to attribute knowledge when reminded of the possibility of error, but philosophers are not affected by this reminder; and (c) non-philosophy academics are overall more skeptical about knowledge than laypeople or philosophers. These findings suggest that academics across a wide range of disciplines share a similar concept of knowledge, and that this concept aligns closely with the intuitions held by laypeople, and differs considerably from the concept of knowledge described in the philosophical literature, as well as the epistemic intuitions of philosophers themselves.     

IS NONDEFECTIVELY JUSTIFIED TRUE BELIEF KNOWLEDGE?

The traditional conception of knowledge as justified true belief is refuted in two famous counterexamples by Edmund L. Gettier. Roderick M. Chisholm has attempted to rescue a version of the traditional conception by distinguishing between defective and nondefective kinds of justification, and redefining knowledge more specifically as nondefectively justified true belief. Chisholm's revised definition avoids Gettier's counterexamples, but goes too far in the opposite direction, imposing conditions that are too narrow and not jointly necessary for knowledge. Chisholm's definition excludes some claims that intuitively constitute genuine knowledge¹ by entailing that if a true belief is invalidated as knowledge when defectively justified by a total body of evidence that also makes evident at least one false proposition, then no knowledge whatsoever can be supported by the same evidence. An alternative analysis of knowledge is proposed, according to which the potential loophole between the state of affairs that justifies belief in a proposition, and the state of affairs that makes the proposition true, permitted by the traditional concept of knowledge and discovered by Gettier's counterexamples, is closed by redefining knowledge as semantically-epistemically evidentially relevant justified true belief.     

Quantifiers and epistemic contextualism

I defend a neo-Lewisean form of contextualism about knowledge attributions. Understanding the context-sensitivity of knowledge attributions in terms of the context-sensitivity of universal quantifiers provides an appealing approach to knowledge. Among the virtues of this approach are solutions to the skeptical paradox and the Gettier problem. I respond to influential objections to Lewis’s account.     

Representationalism, Supervenience, and the Cross-Modal Problem

The representational theory of phenomenal experience is often stated in terms of a supervenience thesis: as Tye has recently put it, “necessarily, experiences that are alike in their representational contents are alike in their phenomenal character”. Consequently, much of the debate over whether representationalism is true centres on purported counter-examples – that is to say, purported failures of supervenience. The discussion here focuses on one important representationalist response to a striking class of these, namely, perceptual states in different sensory modalities that, despite differing phenomenally, share at least some content – for example, the visual and tactile sensations of motion. Some representationalists reply to these cases, in effect, by widening the supervenience base of phenomenal experience to clusters of perceptual contents. However, I argue that this reply radically undermines the representational theory of experience by, among other problems, ruling out its construal as an identity thesis, and leaving the supervenience claim apparently ungrounded.     

Bolzano <Emphasis Type="Italic">a priori</Emphasis> knowledge,and the Classical Model of Science

This paper is aimed at understanding one central aspect of Bolzano’s views on deductive knowledge: what it means for a proposition and for a term to be known a priori. I argue that, for Bolzano, a priori knowledge is knowledge by virtue of meaning and that Bolzano has substantial views about meaning and what it is to know the latter. In particular, Bolzano believes that meaning is determined by implicit definition, i.e. the fundamental propositions in a deductive system. I go into some detail in presenting and discussing Bolzano’s views on grounding, a priori knowledge and implicit definition. I explain why other aspects of Bolzano’s theory and, in particular, his peculiar understanding of analyticity and the related notion of Ableitbarkeit might, as it has invariably in the past, mislead one to believe that Bolzano lacks a significant account of a priori knowledge. Throughout the paper, I point out to the ways in which, in this respect, Bolzano’s antagonistic relationship to Kant directly shaped his own views.     

The Gettier-illusion: Gettier-partialism and infallibilism

Could the standard interpretation of Gettier cases reflect a fundamental confusion? Indeed so. How well can epistemologists argue for the truth of that standard interpretation? Not so well. A methodological mistake is allowing them not to notice how they are simply (and inappropriately) being infallibilists when regarding Gettiered beliefs as failing to be knowledge. There is no Gettier problem that we have not merely created for ourselves by unwittingly being infallibilists about knowledge.