It is tempting to posit an intimate relationship between belief and assertion. The speech act of assertion seems like a way of transferring the speaker’s belief to his or her audience. If this is right, then you might think that the evidential warrant required for asserting a proposition is just the same as the warrant for believing it. We call this thesis entitlement equality. We argue here that entitlement equality is false, because our everyday notion of belief is unambiguously a (...) weak one. Believing something is true, we argue, is compatible with having relatively little confidence in it. Asserting something requires something closer to complete confidence. Specifically, we argue that believing a proposition merely requires thinking it likely, but that thinking that a proposition is likely does not entitle one to assert it. This conclusion conflict with a standard view that ‘full belief’ is the central commonsense non-factive attitude. (shrink)

A paradox is presented that the poses new problems for both the truth norm and the knowledge norm of belief.

Williamson (2000) appeals to considerations about when it is natural to say that a hypothesis is consistent with one’s evidence in order to motivate the claim that all and only knowledge is evidence. It is argued here that the relevant considerations do not support this claim, and in fact conflict with it.

Epistemologists can be divided into two camps: those who think that nothing short of certainty or (subjective) probability 1 can warrant assertion and those who disagree with this claim. This paper addressed this issue by inquiring into the problem of setting the probability threshold required for assertion in such a way that that the social epistemic good is maximized, where the latter is taken to be the veritistic value in the sense of Goldman (Knowledge in a social world, 1999). We (...) provide a Bayesian model of a test case involving a community of inquirers in a social network engaged in group deliberation regarding the truth or falsity of a proposition $p.$ p . Results obtained by means of computer simulation indicate that the certainty rule is optimal in the limit of inquiry and communication but that a lower threshold is preferable in less idealized cases. (shrink)

Paul Horwich’s Use Theory of Meaning (UTM) depends on his rejection of Paul Grice’s distinction between natural and non-natural meaning and his Univocality of Meaning Thesis, as he wishes to deflate the meaning-relation to usage. Horwich’s programme of deflating the meaning-relation (i.e. how words, sentences, etc., acquire meaning) to some basic regularity of usage cannot be carried through if the meaning-relation depends on the minds of users. Here, I first give a somewhat detailed account of the distinction between natural and (...) non-natural meaning in order to set the stage for Horwich’s critique of it. I then present Horwich’s critique of the distinction and show how that rejection accords with his overall view of meaning as use. Horwich’s rejection of the distinction between natural and non-natural meaning, I argue in the last section, is ill founded, and because UTM depends on this rejection, UTM is stillborn. (shrink)

Certain puzzling cases have been discussed in the literature recently which appear to support the thought that knowledge can be obtained by way of deduction from a falsehood; moreover, these cases put pressure, prima facie, on the thesis of counter closure for knowledge. We argue that the cases do not involve knowledge from falsehood; despite appearances, the false beliefs in the cases in question are causally, and therefore epistemologically, incidental, and knowledge is achieved despite falsehood. We also show that the (...) principle of counter closure, and the concomitant denial of knowledge from falsehood, is well motivated by considerations in epistemological theory--in particular, by the view that knowledge is first in the epistemological order of things. (shrink)

Timothy Williamson has fruitfully exploited formal resources to shed considerable light on the nature of knowledge. In the paper under examination, Williamson turns his attention to Gettier cases, showing how they can be motivated formally. At the same time, he disparages the kind of justification he thinks gives rise to these cases. He favors instead his own notion of justification for which Gettier cases cannot arise. We take issue both with his disparagement of the kind of justification that figures in (...) Gettier cases and the specifics of the formal motivation. (shrink)

Looking out the window, I see that it's raining outside. Do I know that it’s raining outside? According to proponents of the Entailment Thesis, I do. If I see that p, I know that p. In general, the Entailment Thesis is the thesis that if S perceives that p, S knows that p. But recently, some philosophers (McDowell 2002, Turri 2010, Pritchard 2011, 2012) have argued that the Entailment Thesis is false. On their view, we can see p and not (...) know that p. In this paper, I argue that their arguments are unsuccessful. (shrink)

I defend a perceptual account of face-to-face mindreading. I begin by proposing a phenomenological constraint on our visual awareness of others' emotional expressions. I argue that to meet this constraint we require a distinction between the basic and non-basic ways people, and other things, look. I offer and defend just such an account.

In this paper we present the comparative study by Jonathan Stoltz, about the similarities between Timothy Williamson's epistemology and the Indo-Tibetan epistemological traditions that developed between the eighth and thirteenth centuries, which lie above that for them the knowledge is a kind of mental state as well as a restricted study of the return to metaphysics, a name that refers to the interesting position of authority born of an attempt to overcome his classical and strong Anglo-American analytical roots.

Can we explain why some propositions are necessary? Blackburn (Fact, science, and value. Blackwell, Oxford, 1987) has presented a dilemma aimed at showing that the necessity of a proposition cannot be explained either in the case where the explanans is another necessary proposition (necessity horn) or in the case where the explanans is a contingent proposition (contingency horn). Blackburn’s dilemma is intended to show that necessary truth is an explanatorily irreducible kind of truth: there is nothing that explains why propositions (...) are necessary, nothing that makes necessary necessary truths. In this paper, I criticize the contingency horn of Blackburn’s dilemma. On the one hand, I show that the official reconstruction of the horn uses a principle that is incompatible with the notion of explanation plausibly needed to explain why propositions are necessary; on the other, I show that a simpler formulation of the horn, which does not make use of such a controversial principle, makes essential use of principles that are incompatible with the idea that possibilities can have explanatory roles. I then defend the view that possibilities can have explanatory roles, and that the explanatory role of possibilities is best represented, within possible worlds, as the existence of trans-world relations of explanation. (shrink)

By “epistemic pragmatism” in general I will understand the claim that whether propositions instantiate certain key epistemic properties (such as being known or being justifiably believed) depends not just on factors traditionally recognized as epistemic, but also on pragmatic factors, such as how costly it would be to the subject if the proposition were false. In what follows I consider two varieties of epistemic pragmatism. According to what I shall call moderate epistemic pragmatism, how much evidence we need in favor (...) of a proposition in order to know that the proposition is true depends on our preferences. According to what I shall call extreme epistemic pragmatism, on the other hand, our preferences influence our epistemic position at a more basic level, because they help determine how much justification we actually have in favor of the proposition in question. Simplifying brutally, moderate epistemic pragmatism has it that the more worried we are about a proposition’s being false, the more justification we need in order to know it, whereas extreme epistemic pragmatism has it that the more worried we are about a proposition’s being false, the less justification we have for it. Recently, Fantl and McGrath have presented an interesting argument for moderate epistemic pragmatism, an argument which relies on the principle that (roughly) knowledge is sufficient for action (KA). In this paper I argue that KA, together with a plausible principle about second-order evidence, entails extreme epistemic pragmatism. (shrink)

I describe two traditions of philosophical accounts of evidence: one characterizes the notion in terms of signs of success, the other characterizes the notion in terms of conditions of success. The best examples of the former rely on the probability calculus, and have the virtues of generality and theoretical simplicity. The best examples of the latter describe the features of evidence which scientists appeal to in practice, which include general features of methods, such as quality and relevance, and general features (...) of evidence, such as patterns in data, concordance with other evidence, and believability of the evidence. Two infamous episodes from biomedical research help to illustrate these features. Philosophical characterization of these latter features—conditions of success—has the virtue of potential relevance to, and descriptive accuracy of, practices of experimental scientists. (shrink)

Many views rely on the idea that it can never be rational to have high confidence in something like, “P, but my evidence doesn’t support P.” Call this idea the “Non-Akrasia Constraint”. Just as an akratic agent acts in a way she believes she ought not act, an epistemically akratic agent believes something that she believes is unsupported by her evidence. The Non-Akrasia Constraint says that ideally rational agents will never be epistemically akratic. In a number of recent papers, the (...) Non-Akrasia Constraint has been called into question. The goal of this paper is to defend it... for the most part. (shrink)

The paper starts by describing and clarifying what Williamson calls the consequence fallacy. I show two ways in which one might commit the fallacy. The first, which is rather trivial, involves overlooking background information; the second way, which is the more philosophically interesting, involves overlooking prior probabilities. In the following section, I describe a powerful form of sceptical argument, which is the main topic of the paper, elaborating on previous work by Huemer. The argument attempts to show the impossibility of (...) defeasible justification, justification based on evidence which does not entail the (allegedly) justified proposition or belief. I then discuss the relation between the consequence fallacy, or some similar enough reasoning, and that form of argument. I argue that one can resist that form of sceptical argument if one gives up the idea that a belief cannot be justified unless it is supported by the totality of the evidence available to the subject—a principle entailed by many prominent epistemological views, most clearly by epistemological evidentialism. The justification, in the relevant cases, should instead derive solely from the prior probability of the proposition. A justification of this sort, that does not rely on evidence, would amount to a form of entitlement, in (something like) Crispin Wright’s sense. I conclude with some discussion of how to understand prior probabilities, and how to develop the notion of entitlement in an externalist epistemological framework. (shrink)

The swamping problem is the problem of explaining why reliabilist knowledge (reliable true belief) has greater value than mere true belief. Swamping problem advocates see the lack of a solution to the swamping problem (i.e., the lack of a value-difference between reliabilist knowledge and mere true belief) as grounds for rejecting reliabilism. My aims here are (i) to specify clear requirements for a solution to the swamping problem that are as congenial to reliabilism's critics as possible, (ii) to clear away (...) various existing reliabilist solutions on the basis of these requirements, and (iii) to present a reliabilist solution that succeeds in meeting all of them. To meet all the requirements, my solution develops a more nuanced understanding of the epistemic end than is currently discussed, and with it a novel way of individuating beliefs. I close with a brief discussion of the question whether reliabilism's critics might impose further demands which reliabilism cannot possibly meet. (shrink)

Invited contribution to The Aim of Belief, a special issue of Teorema, guest-edited by J. Zalabardo.

This paper starts by giving an interpretation of the notorious question "Why be moral?" Then, to answer that question, it develops an account of why some moral reasons -- specifically, the moral reasons that ground moral requirements -- are sufficiently weighty that they outweigh all countervailing reasons for action.

It is highly now intuitive that the future is open and the past is closed now—whereas it is unsettled whether there will be a fourth world war, it is settled that there was a first. Recently, it has become increasingly popular to claim that the intuitive openness of the future implies that contingent statements about the future, such as ‘There will be a sea battle tomorrow,’ are non-bivalent (neither true nor false). In this paper, we argue that the non-bivalence of (...) future contingents is at odds with our pre-theoretic intuitions about the openness of the future. These intuitions are revealed by our pragmatic judgments concerning the correctness and incorrectness of assertions of future contingents. We argue that the pragmatic data together with a plausible account of assertion shows that in many cases we take future contingents to be true (or to be false), though we take the future to be open in relevant respects. It follows that appeals to intuition to support the non-bivalence of future contingents are untenable. Intuition favours bivalence. (shrink)

This paper explores how the purpose of the concept of knowledge affects knowledge ascriptions in natural language. I appeal to the idea that the role of the concept of knowledge is to flag reliable informants, and I use this idea to illuminate and support contextualism about ‘knows’. I argue that practical pressures that arise in an epistemic state of nature provide an explanatory basis for a brand of contextualism that I call ‘practical interests contextualism’. I also answer some questions that (...) contextualism leaves open, particularly why the concept of knowledge is valuable, why the word ‘knows’ exhibits context-variability, and why this term enjoys such widespread use. Finally, I show how my contextualist framework accommodates plausible ideas from two rival views: subject-sensitive invariantism and insensitive invariantism. This provides new support for contextualism and develops this view in a way that improves our understanding of the concept of knowledge. (shrink)

In Republic V, Plato distinguishes two different cognitive powers, knowledge and belief, which operate differently on different types of object. I argue that in Republic VI Plato modifies this account, and claims that there is a single cognitive power, which under different circumstances behaves either as knowledge or as belief. I show that the circumstances which turn true belief into knowledge are the provision of an individuation account of the object of belief, which reveals the ontological status and the nature (...) of the object. Plato explores many alternative candidates of individuation accounts of objects of true belief, which he discards. I conclude with a Platonic sketch of a teleological account of individuation which would satisfy his requirements of turning true belief into knowledge. (shrink)

I outline a number of parallels between trust and distrust, emphasising the significance of situations in which both trust and distrust would be an imposition upon the (dis)trustee. I develop an account of both trust and distrust in terms of commitment, and argue that this enables us to understand the nature of trustworthiness. Note that this article is available open access on the journal website.

According to an influential conception of reasons for action, the presence of a desire or some other conative state in the agent is a necessary condition for the agent’s havinga reason for action. This is sometimes known as internalism . In this paper I present a case for the considerably stronger thesis, which I call hyper-internalism , that the presence of a desire is a sufficient condition for the agent’s having a ( prima facie )reason for action.

Current epistemological orthodoxy has it that knowledge is incompatible with luck. More precisely: Knowledge is incompatible with epistemic luck . This is often treated as a truism which is not even in need of argumentative support. In this paper, I argue that there is lucky knowledge. In the first part, I use an intuitive and not very developed notion of luck to show that there are cases of knowledge which are “lucky” in that sense. In the second part, I look (...) at philosophical conceptions of luck and come to the conclusion that knowledge can be lucky in those senses, too. I also turns out that a probabilistic notion of luck can help us see in what ways a particular piece of knowledge or belief can be lucky or not lucky. (shrink)

This article develops a social epistemological analysis of Web-based search engines, addressing the following questions. First, what epistemic functions do search engines perform? Second, what dimensions of assessment are appropriate for the epistemic evaluation of search engines? Third, how well do current search engines perform on these? The article explains why they fulfil the role of a surrogate expert, and proposes three ways of assessing their utility as an epistemic tool—timeliness, authority prioritisation, and objectivity. “Personalisation” is a current trend in (...) Internet-delivered services, and consists in tailoring online content to the interests of the individual user. It is argued here that personalisation threatens the objectivity of search results. Objectivity is a public good; so there is a prima facie case for government regulation of search engines. (shrink)

Most epistemologists hold that knowledge entails belief. However, proponents of this claim rarely offer a positive argument in support of it. Rather, they tend to treat the view as obvious and assert that there are no convincing counterexamples. We find this strategy to be problematic. We do not find the standard view obvious, and moreover, we think there are cases in which it is intuitively plausible that a subject knows some proposition P without—or at least without determinately—believing that P. Accordingly, (...) we present five plausible examples of knowledge without (determinate) belief, and we present empirical evidence suggesting that our intuitions about these scenarios are not atypical. (shrink)

Claims of the form 'I know P and it might be that not-P' tend to sound odd. One natural explanation of this oddity is that the conjuncts are semantically incompatible: in its core epistemic use, 'Might P' is true in a speaker's mouth only if the speaker does not know that not-P. In this paper I defend this view against an alternative proposal that has been advocated by Trent Dougherty and Patrick Rysiew and elaborated upon in Jeremy Fantl and Matthew (...) McGrath's recent Knowledge in an Uncertain World. (shrink)

A large chorus of voices has grown around the claim that theistic belief is epistemically suspect since, as some cognitive scientists have hypothesized, such beliefs are a byproduct of cognitive mechanisms which evolved for rather different adaptive purposes. This paper begins with an overview of the pertinent cognitive science followed by a short discussion of some relevant epistemic concepts. Working from within a largely Williamsonian framework, we then present two different ways in which this research can be formulated into an (...) argument against theistic belief. We argue that neither version works. (shrink)

One of the main arguments intended to show that content externalism undermines the privileged access thesis is the ‘slow switching argument’, originally proposed by Boghossian. In this argument, it is supposed that a subject is unknowingly switched back and forth between Earth and Twin Earth: then it is claimed that, given externalism, when the subject is on Earth thinking that water is wet, he cannot know the content of his thought a priori, for he cannot, by mere reflection, rule out (...) the relevant alternative hypothesis that he is on Twin Earth thinking that twater is wet. One of the controversies surrounding this argument stems from the fact that it is not clear which epistemological principle underlies it. Here, I examine two suggestions made in the literature as to what that underlying principle might be. I argue that neither of these suggested principles is plausible, and thus that the slow switching argument never gets off the ground. (shrink)

Epistemic transparency tells us that, if an agent S knows a given proposition p , then S knows that she knows that p . This idea is usually encoded in the so-called KK principle of epistemic logic. The paper develops an argument in favor of a moderate version of KK , which I dub quasi-transparency , as a normative rather than a descriptive principle. In the second Section I put forward the suggestion that epistemic transparency is not a demand of (...) ideal rationality, but of ideal epistemic responsibility, and hence that ideally responsible agents verify transparency principles of some sort; I also contend that their satisfaction should not be tied to an internalist epistemology. The central argument in favor of transparency is then addressed in Sections 3 to 8, through the development of a formal system. I show that, in a well-behaved formal setting, a moderate version of transparency is imposed upon us as a result of a number of independent decisions on the structure of higher-order probabilities, as long as we request that our probability and knowledge attributions cohere with each other. Thus I give a rationale to build a model for a hierarchy of languages with different levels of knowledge and probability operators; we obtain an analogous to KK for successive knowledge operators without actually demanding transitivity. The formal argument reinforces the philosophical intuition that epistemic transparency is an important desideratum we should not be too ready to dismiss. (shrink)

Alexander Bird and Darrell Rowbottom have argued for two competing accounts of the concept of scientific progress. For Bird, progress consists in the accumulation of scientific knowledge. For Rowbottom, progress consists in the accumulation of true scientific beliefs. Both appeal to intuitions elicited by thought experiments in support of their views, and it seems fair to say that the debate has reached an impasse. In an attempt to avoid this stalemate, we conduct a systematic study of the factors that underlie (...) judgments about scientific progress. Our results suggest that (internal) justification plays an important role in intuitive judgments about progress, questioning the intuitive support for the claim that the concept of scientific progress is best explained in terms of the accumulation of only true scientific belief. (shrink)

Knowledge is widely thought to entail belief. But Radford has claimed to offer a counterexample: the case of the unconfident examinee. And Myers-Schulz and Schwitzgebel have claimed empirical vindication of Radford. We argue, in defense of orthodoxy, that the unconfident examinee does indeed have belief, in the epistemically relevant sense of dispositional belief. We buttress this with empirical results showing that when the dispositional conception of belief is specifically elicited, people’s intuitions then conform with the view that knowledge entails (dispositional) (...) belief. (shrink)

Bootstrapping is a suspicious form of reasoning that verifies a source's reliability by checking it against itself. Theories that endorse such reasoning face the bootstrapping problem. This article considers which theories face the problem, and surveys potential solutions. The initial focus is on theories like reliabilism and dogmatism, which allow one to gain knowledge from a source without knowing that it is reliable. But the discussion quickly turns to a more general version of the problem that does not depend on (...) this allowance. Five potential solutions to the general problem are evaluated, and some implications for the literature on peer disagreement are considered. (shrink)

Understanding enjoys a special kind of value, one not held by lesser epistemic states such as knowledge and true belief. I explain the value of understanding via a seemingly unrelated topic, the implausibility of veritism. Veritism holds that true belief is the sole ultimate epistemic good and all other epistemic goods derive their value from the epistemic value of true belief. Veritism entails that if you have a true belief that p, you have all the epistemic good qua p. Veritism (...) is a plausible and widely held view; I argue that it is untenable. I argue that integration among beliefs possesses epistemic value independent from the good of true belief, and so has value veritism cannot account for. I argue further that this integration among beliefs comprises the distinctive epistemic value of understanding. (shrink)

An argument is epistemically self-defeating when either the truth of an argument’s conclusion or belief in an argument’s conclusion defeats one’s justification to believe at least one of that argument’s premises. Some extant defenses of the evidentiary value of intuition have invoked considerations of epistemic self-defeat in their defense. I argue that there is one kind of argument against intuition, an unreliability argument, which, even if epistemically self-defeating, can still imply that we are not justified in thinking intuition has evidentiary (...) value. (shrink)

Reliabilism is a theory that countenances basic knowledge, that is, knowledge from a reliable source, without requiring that the agent knows the source is reliable. Critics (especially Cohen 2002 ) have argued that such theories generate all-too-easy, intuitively implausible cases of higher-order knowledge based on inference from basic knowledge. For present purposes, the criticism might be recast as claiming that reliabilism implausibly generates cases of understanding from brute, basic knowledge. I argue that the easy knowledge (or easy understanding) criticism rests (...) on an implicit mischaracterization of the notion of a reliable process. Properly understood, reliable processes do not permit the transition from basic knowledge to understanding based on inference. (shrink)

Abstract This paper develops an explanationist treatment of the problem of the criterion. Explanationism is the view that all justified reasoning is justified in virtue of the explanatory virtues: simplicity, fruitfulness, testability, scope, and conservativeness. A crucial part of the explanationist framework is achieving wide reflective equilibrium. I argue that explanationism offers a plausible solution to the problem of the criterion. Furthermore, I argue that a key feature of explanationism is the plasticity of epistemic judgments and epistemic methods. The explanationist (...) does not offer any fixed judgments or methods to guide epistemic conduct; even the explanatory virtues themselves are subject to change. This feature of explanationism gives it an advantage over non-explanationist views that offer fixed epistemic judgments and epistemic methods. The final section of this paper responds to objections to explanationism. (shrink)

Many contemporary epistemologists hold that a subject S’s true belief that p counts as knowledge only if S’s belief that p is also, in some important sense, safe. I describe accounts of this safety condition from John Hawthorne, Duncan Pritchard, and Ernest Sosa. There have been three counterexamples to safety proposed in the recent literature, from Comesaña, Neta and Rohrbaugh, and Kelp. I explain why all three proposals fail: each moves fallaciously from the fact that S was at epistemic risk (...) just before forming her belief to the conclusion that S’s belief was formed unsafely. In light of lessons from their failure, I provide a new and successful counterexample to the safety condition on knowledge. It follows, then, that knowledge need not be safe. Safety at a time depends counterfactually on what would likely happen at that time or soon after in a way that knowledge does not. I close by considering one objection concerning higher-order safety. (shrink)

Adequate epistemic justification is best conceived as the appearance, over time, of knowledge to the subject. ‘Appearance’ is intended literally, not as a synonym for belief. It is argued through consideration of examples that this account gets the extension of ‘adequately justified belief’ at least roughly correct. A more theoretical reason is then offered to regard justification as the appearance of knowledge: If we have a knowledge norm for assertion, we do our best to comply with this norm when we (...) express as assertions only beliefs that appear to us to be knowledge. If we are doing our best, there is little point in further sanctions. So a norm of knowledge for assertion would lead to a secondary norm of justified belief as the appearance of knowledge, marking a point at which our assertions may be corrected but should not be blamed. (shrink)

What is the connection between justification and the kind of consequence relations that are studied by logic? In this essay, I shall try to provide an answer, by proposing a general conception of the kind of inference that counts as justified or rational.

How does the monitoring of a testifier's credibility by recipients of testimony bear upon the epistemic licence accruing to a recipient's belief in the testifier's communications? According to an intuitive and philosophically influential conception, licensed acceptance of testimony requires that recipients of testimony monitor testifiers with respect to their credibility. I argue that this conception, however, proves to be untenable when confronted with the wealth of empirical evidence bearing on the ways in which testifiers and their interlocutors actually interact.

Lewis thought concessive knowledge attributions (e.g., ‘I know that Harry is a zebra, but it might be that he’s just a cleverly disguised mule’) caused serious trouble for fallibilists. As he saw it, CKAs are overt statements of the fallibilist view and they are contradictory. Dougherty and Rysiew have argued that CKAs are pragmatically defective rather than semantically defective. Stanley thinks that their pragmatic response to Lewis fails, but the fallibilist cause is not lost because Lewis was wrong about the (...) commitments of fallibilism. There are problems with Dougherty and Rysiew’s response to Stanley and there are problems with Stanley’s response to Lewis. I’ll offer a defense of fallibilism of my own and show that fallibilists needn’t worry about CKAs. (shrink)

The problem of easy knowledge arises for theories that have what I call a “basic knowledge structure”. S has basic knowledge of P just in case S knows P prior to knowing that the cognitive source of S's knowing P is reliable.1 Our knowledge has a basic knowledge structure (BKS) just in case we have basic knowledge and we come to know our faculties are reliable on the basis of our basic knowledge. The problem I raised in “Basic Knowledge and (...) the Problem of Easy Knowledge”2 (BKEK) is that once we allow for basic knowledge, we can come to know our faculties are reliable in ways that intuitively are too easy. This raises a serious doubt about whether we had the basic knowledge in the first place. In “Easy Knowledge”, Peter Markie argues that BKS theories do not face any problem concerning easy knowledge.3 I argued that the problem arises in two forms, and Markie takes issue with both. I will argue that Markie's defense of BKS theories fails. (shrink)

According to a doctrine that I call “Cartesianism”, knowledge – at least the sort of knowledge that inquirers possess – requires having a reason for belief that is reflectively accessible as such. I show that Cartesianism, in conjunction with some plausible and widely accepted principles, entails the negation of a popular version of Fallibilism. I then defend the resulting Cartesian Infallibilist position against popular objections. My conclusion is that if Cartesianism is true, then Descartes was right about this much: for (...) S to know that p, S must have reasons for believing that p which are such that S can know, by reflection alone, that she has those reasons, and that she could not possibly have those reasons if p is not true. Where Descartes went wrong was in thinking that our ordinary, fallible, non-theologically grounded sources of belief (e.g., perception, memory, testimony), cannot provide us with such reasons. (shrink)