I argue that to know that a proposition is true one must have justification for being certain that the proposition is true. That is, one must have infallible epistemic justification for believing the proposition. It is widely accepted among epistemologists that we rarely, if ever, have such strong justification for our beliefs. It follows that there is precious little that we know. That conclusion is unacceptable to many philosophers. I argue that the positions that lead to the skeptical conclusion are (...) well-motivated and that the skeptical conclusion is implicitly accepted by ordinary speakers. My dissertation has three main components: a metaphilosophical position, an epistemological position, and an error theory. First, the metaphilosophical position. One very important part of philosophy is the analysis of our ordinary concepts. Analysis of our concepts begins with reflecting on what we are inclined to say about various actual and possible cases when considered under specific descriptions. This traditional method has recently come under attack, due in part to the rise of semantic externalism. I agree with externalists that if ‘meaning is reference’ then there is little reason to think reflecting on our concepts from the armchair will provide insight to the nature of the concepts we investigate. I defend a version of semantic internalism which grounds meaning in factors with which subjects are directly acquainted. That view supports the traditional methodology. Furthermore, as the goal of philosophical analysis is to accurately describe concepts of philosophical interest, the only kind of objection that could be decisive against a proposed analysis is that it does not correctly describe our concept. That opens the door to a skeptical analysis of knowledge. Second, the epistemological position. I argue that the unacceptability of sentences of the form “S knows that p but it is possible for S that not-p” is best explained by the hypothesis that our concept of knowledge requires having justification for being certain that what one believes is true. I offer as a criterion of justified certainty the idea that when one knows a proposition is true, one is in a position to decisively answer questions about one’s knowledge of that proposition. I survey a number of competing theories of knowledge and show that they allow for the possibility of knowledge when one fails my criterion of decisive answerability. Those views fail my criterion because according to those views there is nothing the subject is aware of that guarantees for the subject that the allegedly known proposition is true. On that basis, I contend that knowledge is direct awareness of the factors that constitute the truth of the proposition one believes. Third, the error theory. Of course, we rarely have direct awareness of the factors that constitute the truth of the propositions we believe. So, our knowledge attributions are generally false. Yet, they are overwhelmingly natural to make. I argue that competent speakers are often quick to recognize knowledge attributions as a kind of ‘loose talk’ akin to the way we loosely ascribe geometric properties to ordinary objects. We regularly call objects ‘square’ that are not even close to being square, and we are quick to recognize this when challenged. I argue that we do this because we are so accustomed to communicating using strict language to make false claims that we often do not attend to the literal falsity of what we are saying. While we accept very demanding standards for knowledge, the phenomenon of recognizing that our knowledge claims are regularly false is as pervasive as our use of loose speech. (shrink)

The relevance of any logical analysis lies in its ability to solve paradoxes and trace conceptual troubles back; with this respect, the task of epistemic logic is to handle paradoxes in connection with the concept of knowledge. Epistemic logic is currently introduced as the logical analysis of crucial concepts within epistemology, namely: knowledge, belief, truth, and justification. An alternative approach will be advanced here in order to enlighten such a discourse, as centred upon the word assertion and displayed in terms (...) of utterance. Insofar as epistemic modalities express some attitudes, the intentionality of discourse will be emphasized within an illocutionary modal logic. Two large views will range over the whole study: declarative and epistemic sentences have one and the same logic (assertion logic); the plurality of languages games doesn’t entail any logical pluralism. -/- La valeur d'une analyse logique réside dans sa capacité à résoudre des paradoxes et à comprendre l'origine de nos problèmes conceptuels ; à ce titre, le rôle d'une logique épistémique est de traiter des paradoxes liés au concept de connaissance. On présente généralement la logique épistémique comme une analyse logique de concepts centraux en épistémologie : connaissance, croyance, vérité, justification. Une autre approche sera proposée ici en vue de clarifier ce genre de discours, centrée sur la notion d'assertion et décrite en termes d'énonciation. Parce que les modalités épistémiques expriment des attitudes, c'est l'intentionnalité du discours qui sera mise en valeur dans le cadre d'une logique modale illocutoire. Deux thèses transversales parcourront l'ensemble du travail : les énoncés déclaratifs et épistémiques partagent la même logique (logique assertorique) ; la pluralité des jeux de langages n'implique pas un pluralisme logique. (shrink)

More often than not, theories of belief and of belief ascription restrict themselves to conscious beliefs, thus obliterating a vast part of our mental life and offering extremely incomplete, unrealistic theories. Indeed, conscious beliefs are the exception, not the rule, as far as human doxastic states are concerned, and a naturalistic, realistic theory of knowledge that aspires to completeness has to take unconscious beliefs into consideration. This paper is the elaboration of such a theory of belief.

Human social intelligence includes a remarkable power to evaluate what people know and believe, and to assess the quality of well- or ill-formed beliefs. Epistemic evaluations emerge in a great variety of contexts, from moments of deliberate private reflection on tough theoretical questions, to casual social observations about what other people know and think. We seem to be able to draw systematic lines between knowledge and mere belief, to distinguish justified and unjustified beliefs, and to recognize some beliefs as delusional (...) or irrational. This article outlines the main types of epistemic evaluations, and examines how our capacities to perform these evaluations develop, how they function at maturity, and how they are deployed in the vital task of sorting out when to believe what others say. (shrink)

Knowledge is important for us, human beings, for a variety of reasons, starting with trivial but necessary reasons to live your life. Western man also has a collective project that is constitutive of its culture: science; and the aim of science is to gather knowledge about the world in its broadest meaning: from the origin of a particular disease to the origin of man, life, planet Earth and the universe, from why the orbits move as they do to why a (...) mass of people behaves differently from individuals, from why the sky is blue to why the sea is salty, from why the climate seems to change to why rainbows appear, etc. etc. The quest to understand what knowledge is, is as old as philosophy itself, and the philosophy o. (shrink)

In this paper I challenge the orthodox view of the significance of Platonic value problems. According to this view, such problems are among the central questions of epistemology, and answering them is essential for justifying the status of epistemology as a major branch of philosophical enquiry. I challenge this view by identifying an assumption on which Platonic value problems are based – the value assumption – and considering how this assumption might be resisted. After articulating a line of thought that (...) supports the assumption, I highlight one way of undermining it, which is to deny that we desire knowledge and not just (e.g.) true belief because we prefer knowledge to true belief. I then consider an attempt to undermine the value assumption in this way, inspired by Bernard Williams. I contend that Williams's argument fails, but also that seeing why it fails is instructive for future attempts to resist the value assumption. (shrink)

I review several theoretical and empirical developments relevant to assessing contemporary virtue epistemology’s theory of knowledge. What emerges is a leaner theory of knowledge that is more empirically adequate, better captures the ordinary conception of knowledge, and is ripe for cross-fertilization with cognitive science. I call this view abilism. Along the way I identify several topics for future research.

In this paper the relevance of so-called "propositional knowledge" is at first compared witho ther forms of knowledge. Secondly,the traditional and standard definition of propositional knowledge as justified true belief is discussed and defended against its most relevant objections. The third and main focus of this paper is a discussion of Gettier's objection to the tradicional definition and some answers to it,with the purpose of developing a more elaborate version of the traditional definition, one which makes it immune to counter-examples, (...) such as those of the Gettier type. (shrink)