Defeasibility Theory of Knowledge

This paper argues for a responsibilist account of knowledge: S knows that p iff S believes the truth that p (rather than one of the alternatives to p) because S forms/retains the belief in a way that is ultima facie epistemically responsible. This account implies that knowing that p requires neither having evidence that favors p over ∼p, nor possessing reliabilist virtues, nor exhibiting responsibilist virtues or motives.

This dissertation is about the relationship between Epistemology and other domains. In it I want to show that in an important sense, Epistemology is an autonomous domain. That is, epistemic vocabulary (e.g., “knowledge”, “justification”, “rationality”, “epistemic reason”, etc.) cannot be analyzed without remainder into non-epistemic vocabulary. Epistemic phenomena must be explained in terms of epistemic reasons and the form of assessment proprietary to them. Although epistemic vocabulary cannot be reduced to the vocabulary of other domains, Epistemology is nonetheless connected with (...) other domains in an important way. In this dissertation I focus on the connection between Epistemology and the Philosophy of Mind. I distinguish different forms cognitive self-monitoring can take and corresponding forms of cognitive autonomy. The kind of self-monitoring that receives the most attention involves simulating interpersonal argumentation. I argue that the capacity to self-monitor in this way grounds familiar epistemic standards (e.g., knowledge and justification) and explains how reasons get their grip on us. On the picture that emerges, Epistemology and Philosophy of Mind need to be done in tandem. Epistemology gives us the normative framework that is modeled by the self-monitoring system. The self-monitoring system, conversely, explains the kind of activity we engage in that makes that normative framework applicable to us. Epistemic reasons themselves are just episodes of this kind of activity. In Chapter 1 I argue that epistemic luck cannot be analyzed in non-epistemic terms. Here I generalize Jennifer Lackey’s criticism of Duncan Pritchard’s safety-based account of epistemic luck to all reductive theories. I argue that they will either be extensionally inadequate, or they will illicitly presuppose the vocabulary they are trying to reduce. The upshot is that epistemic luck can only be understood in terms of the epistemic assessment of reasons. By extension, we can’t give a reductive analysis of knowledge. This is not to say we cannot analyze knowledge, just that we can’t analyze away the epistemic vocabulary without remainder. In chapter 2 I explain the relation between epistemic luck, epistemic justification, and knowledge. I argue that previous work in the defeasible reasoning tradition, despite being on the right track, fell short of realizing its full potential. This is because the account of how these three things relate given by its proponents was insufficiently unified, which encouraged many epistemologists to abandon the defeasible reasoning tradition entirely. I argue that a unified and principled account of their relation is possible, and it allows for an elegant analysis of knowledge. In slogan form: good reasons are apparent to the knowing subject. In chapter 3 I extend the defeasible reasoning tradition to explain how knowledge is gradable. I show that this enables us to bring the debates about fake barns and knowledge from falsehoods to ecumenical resolutions, while also shedding light on a new kind of case. Furthermore, I explain how background assumptions are themselves defeasible and some of the epistemic significance of this fact. In chapter 4 I make the connection between Epistemology and Philosophy of Mind. I argue that the self-monitoring system of cognitively mature humans uses a model of the normative framework described in the previous chapters to regulate its own cognition. Here I build on that claim to develop an account of the role played by knowledge and justification in doxastic social coordination. I build on the claim that background assumptions are themselves defeasible to develop an account of the foundations of knowledge according to which they are social but not brutely sociological. In chapter 5 I discuss the relation between the epistemic states of cognitively mature humans, children, and non-human animals. I do this in a way meant to integrate an insight from virtue epistemology into the reasons-first picture developed here: positive epistemic standing is a state attributable to the subject. In chapter 6 I discuss the metaphysics of epistemic reasons. I claim that they are episodes of the activity of reasoning. In the preceding chapters, we get a sense of what that activity involves. Here I argue that the materials developed there put us in a position to understand what epistemic reasons are. This account incorporates the insights of rival positions while sidestepping familiar objections to them. The resulting picture is in line with the non-reductive approach to the epistemic developed so far. In fact, it goes further than other “reasons-first” approaches to Epistemology by claiming that reasons are not only basic within Epistemology, but they are also basic full-stop. One key consideration for my argument here is that reasons are, by their very nature, competitors. Although this point is generally acknowledged in the literature on reasons, its consequences for the metaphysics of reasons hasn’t been. Participants in the debate about the metaphysics of reasons typically try to identify reasons with something (e.g., facts or mental states) that are either not competitors, or only competitors insofar as they constitute, or bear on the epistemic assessment of, episodes of reasoning. (shrink)

I advance a novel argument for an infallibilist theory of knowledge, according to which we know all and only those propositions that are certain for us. I argue that this theory lets us reconcile major extant theories of knowledge, in the following sense: for any of these theories, if we require that its central condition (evidential support, reliability, safety, etc.) obtains to a maximal degree, we get a theory of knowledge extensionally equivalent to infallibilism. As such, the infallibilist can affirm (...) that, when their conditions are suitably interpreted, most post-Gettier theories of knowledge offer necessary and sufficient conditions for knowledge. The infallibilist can thus reconcile major theories of knowledge, and is in a better position to explain the intuitive appeal of these theories than the fallibilist who only accepts one of them, and rejects the rest. (shrink)

I will discuss a variety of cases such that the subject's believing truly is somewhat of an accident, but less so than in a Gettier case. In each case, this is because her reasons are not ultimately undefeated full stop, but they are ultimately undefeated with certain qualifications. For example, the subject's reasons might be ultimately defeated considered in themselves but ultimately undefeated considered as a proper part of an inference to the best explanation that is undefeated without qualification. In (...) each section of the paper, I consider different qualifications and show how in each case we get an epistemic standing I call “coach-class knowledge”. First-class knowledge requires justifying reasons that are undefeated without qualification. Coach-class knowledge only requires qualified lack of defeat. I will use this distinction to bring debates over knowledge from falsehood and fake barns to an ecumenical resolution. In both cases, the subject enjoys coach-class rather than first-class knowledge. I will also show that the defeasible reasoning tradition can better account for graded accidental truth than safety theories. (shrink)

Reasons rationalize beliefs. Reasons, when all goes well, turn true beliefs into knowledge. I am interested in the relationship between these aspects of reasons. Without a proper understanding of their relationship, the theory of knowledge will be less illuminating than it ought to be. I hope to show that previous accounts have failed to account for this relationship. This has resulted in a tendency to focus on justification rather than knowledge. It has also resulted in many becoming skeptical about the (...) prospects for an analysis of knowledge. The skepticism is misplaced and the tendency can be fixed without sacrificing any insights. The solution is to see how good reasons (in a sense to be articulated) are apparent (in a sense to be articulated) to the knowing subject. Once this claim is unpacked, we see that it is an illuminating analysis of knowledge in terms of distinct but intimately related aspects of epistemic assessment. It helps us see the value of knowledge (over and above true belief) and it affords us a unified, “reasons-first” metaepistemology. The resulting picture is neither a familiar kind of internalism or externalism. (shrink)

Here I will develop a naturalistic account of epistemic reflection and its significance for epistemology. I will first argue that thought, as opposed to mere information processing, requires a capacity for cognitive self-regulation. After discussing the basic capacities necessary for cognitive self-regulation of any kind, I will consider qualitatively different kinds of thought that can emerge when the basic capacities enable the creature to interiorize a form of social cooperation. First, I will discuss second-personal cooperation and the kind of thought (...) that emerges from its interiorization. Then, I will discuss third-personal cooperation and the kind of thought that emerges from its interiorization. We will see that epistemic reflection is the interiorized version of interpersonal argumentation, which is the epistemic component of third-personal cooperation. In developing this account, I will draw heavily on the work of Michael Tomasello and other cognitive scientists advocating the “social intentionality hypothesis”. However, I will show how work done in the defeasible reasoning tradition can provide us with a deeper explanation of some claims made by advocates of the social intentionality hypothesis. Additionally, we will see that work done on social intentionality can help us better understand the significance of knowledge and justification as understood by the defeasible reasoning tradition. We will see that the social intentionality hypothesis and the defeasible reasoning tradition are mutually illuminating. By drawing equally on both, I will provide a novel account of the foundations of knowledge. (shrink)

In some recent work, John N.Williams defends a new objection to the defeasibility theory of knowledge. But the objection is of wider interest, since Williams also suggests that this style of objection may undermine other theories of knowledge. I distinguish two versions of Williams’ objection. I then show that the first version relies on false conceptual principles, and the second relies on a specific and dubious conception of the goal of the analysis of knowledge.

This is a collection of new essays written in honor of the work of Peter D. Klein, who has had and continues to have a tremendous influence in the development of epistemology. The essays reflect the breadth and depth of Klein’s work by engaging directly with his views and with the views of his interlocutors.

Is knowledge consistent with literally any credence in the relevant proposition, including credence 0? Of course not. But is credence 0 the only credence in p that entails that you don’t know that p? Knowledge entails belief (most epistemologists think), and it’s impossible to believe that p while having credence 0 in p. Is it true that, for every value of ‘x,’ if it’s impossible to know that p while having credence x in p, this is simply because it’s impossible (...) to believe that p while having credence x in p? If so, is it possible to believe that p while having (say) credence 0.4 in p? These questions aren’t standard epistemological fare, at least in part because many epistemologists think their answers are obvious, but they have unanticipated consequences for epistemology. Let ‘improbabilism’ name the thesis that it’s possible to know that p while having a credence in p below 0.5. Improbabilism will strike many epistemologists as absurd, but careful reflection on these questions reveals that, if improbabilism is false, then all of the most plausible theories of knowledge are also false. Or so I argue in this paper. Since improbabilism is widely rejected by epistemologists (at least implicitly), this paper reveals a tension between all of the most plausible theories of knowledge and a widespread assumption in epistemology. (shrink)

Foundationalism in moral epistemology is a core tenet of ethical intuitionism. According to foundationalism, some moral beliefs can be known without inferential justification; instead, all that is required is a proper understanding of the beliefs in question. In an influential criticism against this view, Walter Sinnott-Armstrong has argued that certain psychological facts undermine the reliability of moral intuitions. He claims that foundationalists would have to show that non-inferentially justified beliefs are not subject to those defeaters, but this would already constitute (...) a form of inference and hence undermine the possibility of noninferential justification. The goal of my paper is to defend foundationalism against Sinnott-Armstrong’s criticism. After presenting his challenge, I first argue that the most promising objection to it fails. This objection makes the case that defeater-defeaters are not part of the justification, but merely preserve the justification which the original claim provides. I object to this argument by distinguishing between weak and robust defeaters; only weak defeaters, I argue, fall outside the scope of justification, and it is an open question whether Sinnott-Armstrong’s defeaters fall into that category. This leads the way to my own criticism of Sinnott-Armstrong’s challenge: foundationalists in moral epistemology are entitled to the use of defeater-defeaters as part of the justification for moral beliefs as long as those defeater-defeaters themselves do not entail moral claims. Therefore, Sinnott-Armstrong’s challenge does not undermine foundationalism. (shrink)

Materialism, reductionism, behaviorism, functionalism, dynamic systems theory and computationalism are popular views, but they were shown by Wittgenstein to be incoherent. The study of behavior encompasses all of human life, but behavior is largely automatic and unconscious and even the conscious part, mostly expressed in language (which Wittgenstein equates with the mind), is not perspicuous, so it is critical to have a framework which Searle calls the Logical Structure of Rationality (LSR) and I call the Descriptive Psychology of Higher Order (...) Thought (DPHOT). After summarizing the framework worked out by Wittgenstein and Searle, as extended by modern reasoning research, I show the inadequacies in Carruther’s views, which pervade most discussions of behavior, including contemporary behavioral sciences. I maintain that his book is an amalgam of two books, one a summary of cognitive psychology and the other a summary of the standard philosophical confusions on the mind with some new jargon added. I suggest that the latter should be regarded as incoherent or as a cartoon view of life and that taking Wittgenstein at his word, we can practice successful self therapy by regarding the mind/body issue as a language/body issue. -/- Those wishing a comprehensive up to date framework for human behavior from the modern two systems view may consult my book ‘The Logical Structure of Philosophy, Psychology, Mind and Language in Ludwig Wittgenstein and John Searle’ 2nd ed (2019). Those interested in more of my writings may see ‘Talking Monkeys--Philosophy, Psychology, Science, Religion and Politics on a Doomed Planet--Articles and Reviews 2006-2019 3rd ed (2019), The Logical Structure of Human Behavior (2019), and Suicidal Utopian Delusions in the 21st Century 4th ed (2019) . (shrink)

According to the Reasoning View about normative reasons, facts about normative reasons for action can be understood in terms of facts about the norms of practical reasoning. I argue that this view is subject to an overlooked class of counterexamples, familiar from debates about Subjectivist theories of normative reasons. Strikingly, the standard strategy Subjectivists have used to respond to this problem cannot be adapted to the Reasoning View. I think there is a solution to this problem, however. I argue that (...) the norms of practical reasoning, like the norms of theoretical reasoning, are characteristically defeasible, in a sense I make precise. Recognizing this property of those norms makes space for a solution to the problem. The resulting view is in a way analogous to the familiar defeasibility theory of knowledge, but it avoids a standard objection to that theory. (shrink)

John N. Williams argued that Peter Klein's defeasibility theory of knowledge excludes the possibility of one knowing that one has (first-order) a posteriori knowledge. He does that by way of adding a new twist to an objection Klein himself answered more than forty years ago. In this paper I argue that Williams' objection misses its target because of this new twist.

I objected that the defeasibility theory of knowledge prohibits you from knowing that you know that p if your knowledge that p is a posteriori. Rodrigo Borges claims that Peter Klein has already satisfactorily answered a version of my objection. He attempts to defend Klein’s reply and argues that my objection fails because a principle on which it is based is false.I will show that my objection is not a version of the old one that Klein attempts (unsuccessfully) to address, (...) that Borges’ defence of Klein’s reply fails and that his argument against my new objection leaves it untouched. (shrink)

Many epistemologists are enamored with a defeat condition on knowledge. In this paper we present some implementation problems for defeatism, understood along either internalist or externalist lines. We then propose that one who accepts a knowledge norm of belief, according to which one ought to believe only what one knows, can explain away much of the motivation for defeatism. This is an important result, because on the one hand it respects the plausibility of the intuitions about defeat shared by many (...) in epistemology; but on the other hand, it obviates the need to provide a unified account of defeat which plays well with the most plausible views of how knowledge fits with evidential probability. (shrink)

In Epistemic Entitlement. The Right to Believe Hannes Ole Matthiessen develops a social externalist account of epistemic entitlement and perceptual knowledge. The basic idea is that positive epistemic status should be understood as a specific kind of epistemic right, that is a right to believe. Since rights have consequences for how others are required to treat the bearer of the right, they have to be publicly accessible. The author therefore suggests that epistemic entitlement can plausibly be conceptualized as a status (...) that is grounded in a publicly observable perceptual situation, rather than in a perceptual experience as current theories of epistemic entitlement state. It is then argued that such a social externalist account of entitlement, in which the perceiver's epistemic perspective becomes relevant only in the exceptional case where an entitlement is challenged, can nevertheless do justice to our central intuitions about first-personal epistemic phenomenology. (shrink)

Defeasibility, most generally speaking, means that given some set of conditions A, something else B will hold, unless or until defeating conditions C apply. While the term was introduced into philosophy by legal philosopher H.L.A. Hart in 1949, today, the concept of defeasibility is employed in many different areas of philosophy. This volume for the first time brings together contributions on defeasibility from epistemology , legal philosophy and ethics and the philosophy of action . The volume ends with an extensive (...) bibliography. (shrink)

Richard Feldman and William Lycan have defended a view according to which a necessary condition for a doxastic agent to have knowledge is that the agent’s belief is not essentially based on any false assumptions. I call this the no-essential-false-assumption account, or NEFA. Peter Klein considers examples of what he calls “useful false beliefs” and alters his own account of knowledge in a way which can be seen as a refinement of NEFA. This paper shows that NEFA, even given Klein’s (...) refinement, is subject to counterexample: a doxastic agent may possess knowledge despite having an essential false assumption. Advocates of NEFA could simply reject the intuition that the example is a case of knowledge. However, if the example is interpreted as not being a case of knowledge, then it can be used as a potential counterexample against both safety and sensitivity views of knowledge. I also provide a further case which, I claim, is problematic for all of the accounts just mentioned. I then propose, briefly, an alternative account of knowledge which handles all these cases appropriately. (shrink)

When epistemologists talk about knowledge, the discussions traditionally include only a small class of other epistemic notions: belief, justification, probability, truth. In this paper, we propose that epistemologists should include an additional epistemic notion into the mix, namely the notion of assuming or taking for granted.

The paper considers contemporary models of presumption in terms of their ability to contribute to a working theory of presumption for argumentation. Beginning with the Whatelian model, we consider its contemporary developments and alternatives, as proposed by Sidgwick, Kauffeld, Cronkhite, Rescher, Walton, Freeman, Ullmann-Margalit, and Hansen. Based on these accounts, we present a picture of presumptions characterized by their nature, function, foundation and force. On our account, presumption is a modal status that is attached to a claim and has the (...) effect of shifting, in a dialogue, a burden of proof set at a local level. Presumptions can be analysed and evaluated inferentially as components of rule-based structures. Presumptions are defeasible, and the force of a presumption is a function of its normative foundation. This picture seeks to provide a framework to guide the development of specific theories of presumption. (shrink)

Applying a theory of psychological modularity, I argue for a theory of defeasibility conditions for the epistemic justification of perceptual beliefs. My theory avoids the extremes of holism (e.g., coherentism and confirmation holism) and of foundationalist theories of non-inferential justification.

John Hawthorne’s marvelous book contains a wealth of arguments and insights based on an impressive knowledge and understanding of contemporary discussion. We can address only a small aspect of the topic. In particular, we will offer our own answers to two questions about knowledge that he discusses.

In this paper I discuss the relation between various properties that have been regarded as important for determining whether or not a belief constitutes a piece of knowledge: its stability, strength and sensitivity to truth, as well as the strength of the epistemic position in which the subject is with respect to this belief. Attempts to explicate the relevant concepts more formally with the help of systems of spheres of possible worlds (à la Lewis and Grove) must take care to (...) keep apart the very different roles that systems of spheres can play. Nozicks sensitivity account turns out to be closer to the stability analysis of knowledge (versions of which I identify in Plato, Descartes, Klein and Lehrer) than one might have suspected. (shrink)

Philosophers have sought to characterize a type of knowledge — what I call real knowledge — which is significantly different from the ordinary concept of knowledge. The concept of knowledge as true, justified belief — what I call knowledge simpliciter — failed to depict the sought after real knowledge because the necessary and jointly sufficient conditions of knowledge simpliciter can be felicitously but accidentally fulfilled. Real knowledge is knowledge simpliciter plus a set of requirements which guarantee that the truth, belief (...) and justification conditions are not accidentally conjoined. Two of those requirements have received considerable attention in recent literature by the defeasibility theorists and the causal theorists. I argue that a third requirement is needed to block the merely coincidental cosatisfaction of the belief and justification conditions and to capture our intuitions about the epistemic agent who possesses real knowledge. That condition ascribes a disposition to the real knower to believe all and only justified propositions in virtue of his/her belief that the propositions are justified. Two consequences of that requirement are discussed: (1) if S really knows that p, then S knows simpliciter that S knows simpliciter that p and (2) the iterative feature of real knowledge mentioned in (1) provides a basis for the rejection of a particularly pernicious form of scepticism. (shrink)

Rich with historical and cultural value, these works are published unaltered from the original University of Minnesota Press editions.

There have been many attempts of late to formulate a satisfactory theory of knowledge with which to replace the traditional justified true belief analysis. Almost all agree that it must be the case that in order for S to know that p; i.) p be true, and ii.) S believe that p. Although many argue that there must be a condition stating that S has adequate evidence for p, requirements other than i.) and ii.) are controversial. The most popular approach (...) taken, however, is the addition of a requirement to the effect that for S to know that p there must be no other evidence against p strong enough to undermine S's belief that p, should this evidence come to S's attention. I shall call such a requirement a “defeasibility condition” and any theory containing such a requirement a defeasibility theory.Defeasibility theories are quite effective in handling a certain kind of difficulty to which theories of knowledge are subject, namely problems dealing with what Harman has termed the social aspect of knowledge. (shrink)

The recently offered, Purported counter-Examples to justified, True belief analyses of knowledge are looked at with some care and all found to be either incoherent or inconclusive. It is argued that justified, True belief analyses are based on sound insight into the concept of knowledge. The distinction between having been justified in claiming to know something and actually having known it is used in an effort to get the discussion of knowledge back on the right track.