What is common knowledge? According to the dominant iterative model, a group of people commonly knows that p if and only if they each individually know that p, and they furthermore each know that they each know that p, and so on to infinity. According to the integrative model proposed in this paper, a group commonly knows that p when its members are united in a state of mind of the type whose contents must be true. Epistemic integration (...) within a group is enabled by symmetrical signalling processes such as eye contact. In conversational dyads, symmetrical processing operates on pairs of signals produced by the two sides in a familiar format: speakers generate content for joint attention in main channel communication, and addressees evaluate that content in backchannel communication. Processes of reinforcement learning shape our pairwise signalling, driving the accumulation of common knowledge, both in response to extrinsic reward for coordinated action, and in response to the intrinsic reward of curiosity. Where the iterative model caps the epistemic performance of the group at the level of its weakest member, the integrative model of common knowledge shows how groups working together can outperform their strongest member working alone. (shrink)

The coordinated attack scenario and the electronic mail game are two paradoxes of common knowledge. In simple mathematical models of these scenarios, the agents represented by the models can coordinate only if they have common knowledge that they will. As a result, the models predict that the agents will not coordinate in situations where it would be rational to coordinate. I argue that we should resolve this conflict between the models and facts about what it would (...) be rational to do by rejecting common knowledge assumptions implicit in the models. I focus on the assumption that the agents have common knowledge that they are rational, and provide models to show that denying this assumption suffices for a resolution of the paradoxes. I describe how my resolution of the paradoxes fits into a general story about the relationship between rationality in situations involving a single agent and rationality in situations involving many agents. (shrink)

An opinionated introduction to philosophical issues connected to common knowledge.

The meaning of an utterance is often enriched by the pragmatic context in which it is uttered. This is because in ordinary conversations we routinely and uncontroversially compress what we say, safe in the knowledge that those interpreting us will ‘add in’ the content we intend to communicate. Does the same thing hold true in the case of legal utterances like ‘This constitution protects the personal rights of the citizen’ or ‘the parliament shall have the power to lay and (...) collect taxes’? This article addresses this question from the perspective of the constitutional originalist—the person who holds that the meaning of a constitutional text is fixed at some historical moment. In doing so, it advances four theses. First, it argues that every originalist theory is committed to some degree of pragmatic enrichment, the debate is about how much. Second, that in determining which content gets ‘added in’, originalists typically hold to a common knowledge standard for enrichment, protestations... (shrink)

Some arguments against the assumption that ordinary people may share common knowledge are sound. The apparent cost of such arguments is the rejection of scientific theories that appeal to common knowledge. My proposal is to accept the arguments without rejecting the theories. On my proposal, common knowledge is shared by ideally rational people, who are not just mathematically simple versions of ordinary people. They are qualitatively different from us, and theorizing about them does not (...) lead to predictions about our behavior. Nevertheless, models of action that assume common knowledge have a role to play in our understanding of collective rationality. (shrink)

We argue that common knowledge, of the kind used in reasoning in law and computing is best analyzed using a dialogue model of argumentation (Walton & Krabbe 1995). In this model, implicit premises resting on common knowledge are analyzed as endoxa or widely accepted opinions and generalizations (Tardini 2005). We argue that, in this sense, common knowledge is not really knowledge of the kind represent by belief and/or knowledge of the epistemic kind (...) studied in current epistemology. This paper takes a different approach, defining it in relation to a common commitment store of two participants in a rule-governed dialogue in which two parties engage in rational argumentation (Jackson & Jacobs 1980; van Eemeren & Grootendorst 2004). A theme of the paper is how arguments containing common knowledge premises can be studied with the help of argumentation schemes for arguments from generally accepted opinion and expert opinion. It is argued that common knowledge is a species of provi- sional acceptance of a premise that is not in dispute at a given point in a dia- logue, but may later be defeated as the discussion proceeds . (shrink)

In this paper it is shown how a formal theory of interpretation in Montague’s style can be reconciled with a view on meaning as a social construct. We sketch a formal theory in which agents can have their own theory of interpretation and in which groups can have common theories of interpretation. Frege solved the problem how different persons can have access to the same proposition by placing the proposition in a Platonic realm, independent from all language users but (...) accessible to all of them. Here we explore the alternative of letting meaning be socially constructed. The meaning of a sentence is accessible to each member of a linguistic community because the way the sentence is to be interpreted is common knowledge among the members of that community. Misunderstandings can arise when the semantic knowledge of two or more individuals is not completely in sync. (shrink)

What is the relation between joint attention and common knowledge? On the one hand, the relation seems tight: the easiest and most reliable way of knowing something in common with another is for you and that other to be attentively aware of what you are together experiencing. On the other hand, they couldn’t seem further apart: joint attention is a mere perceptual phenomena that infants are capable of engaging in from nine months of age, whereas common (...) knowledge is a cognitive phenomenon involving (so it seems) complex, overlapping metarepresentational states that require the kind of sophisticated mindreading skills that developmental psychology has shown to be beyond the capabilities of young children. In 'The Shared World: Perceptual Common Knowledge, Demonstrative Communication, and Shared Social Space', Axel Seemann attempts, inter alia, to makensense of this conundrum. (shrink)

The paper surveys the currently available axiomatizations of common belief (CB) and common knowledge (CK) by means of modal propositional logics. (Throughout, knowledge- whether individual or common- is defined as true belief.) Section 1 introduces the formal method of axiomatization followed by epistemic logicians, especially the syntax-semantics distinction, and the notion of a soundness and completeness theorem. Section 2 explains the syntactical concepts, while briefly discussing their motivations. Two standard semantic constructions, Kripke structures and neighbourhood (...) structures, are introduced in Sections 3 and 4, respectively. It is recalled that Aumann's partitional model of CK is a particular case of a definition in terms of Kripke structures. The paper also restates the well-known fact that Kripke structures can be regarded as particular cases of neighbourhood structures. Section 3 reviews the soundness and completeness theorems proved w.r.t. the former structures by Fagin, Halpern, Moses and Vardi, as well as related results by Lismont. Section 4 reviews the corresponding theorems derived w.r.t. the latter structures by Lismont and Mongin. A general conclusion of the paper is that the axiomatization of CB does not require as strong systems of individual belief as was originally thought- only monotonicity has thusfar proved indispensable. Section 5 explains another consequence of general relevance: despite the "infinitary" nature of CB, the axiom systems of this paper admit of effective decision procedures, i.e., they are decidable in the logician's sense. (shrink)

David Lewis is widely regarded as the philosopher who introduced the concept of common knowledge. His account of common knowledge differs greatly from most later accounts in philosophy and economy, with the central notion of his theory being ‘having reason to believe’ rather than ‘knowledge’. Unfortunately, Lewis’s account is rather informal, and the argument has a few gaps. This paper assesses two major attempts to formalise Lewis’s account and argues that these formalisations are missing a (...) crucial aspect of this account. Therefore, a new reconstruction is proposed, which explicitly discusses ‘reasons’ and uses a logic inspired by justification logic. (shrink)

Few recent developments in information technology have been as hyped as blockchain, the first implementation of which was the cryptocurrency Bitcoin. Such hype furnishes ample reason to be skeptical about the promise of blockchain implementations, but I contend that there’s something to the hype. In particular, I think that certain blockchain implementations, in the right material, social, and political conditions, constitute excellent bases for common knowledge. As a case study, I focus on trust in election outcomes, where the (...) ledger records not financial transactions but vote tallies. I argue that blockchain implementations could foster warranted trust in vote tallies and thereby trust in the democratic process. Finally, I argue that if the promise of blockchain implementations as democratic infrastructure is to be realized, then democracies first need to ensure that these material, social, and political conditions obtain. (shrink)

This chapter explores the idea that the need to establish common knowledge is one feature that makes social cognition stand apart in important ways from cognition in general. We develop this idea on the background of the claim that social cognition is nothing but a type of causal inference. We focus on autism as our test-case, and propose that a specific type of problem with common knowledge processing is implicated in challenges to social cognition in autism (...) spectrum disorder (ASD). This problem has to do with the individual’s assessment of the reliability of messages that are passed between people as common knowledge emerges. The proposal is developed on the background of our own empirical studies and outlines different ways common knowledge might be comprised. We discuss what these issues may tell us about ASD, about the relation between social and non-social cognition, about social objects, and about the dynamics of social networks. (shrink)

In his defense of innateness in New Essays on Human Understanding (1704), Leibniz attributes innateness to concepts and principles which do not originate from the senses rather than to the ideas that we are born with. He argues that the innate concepts and principles can be known in two ways: through reason or natural light (necessary truths), and through instincts (other innate truths and principles). In this paper I will show how theoretical and moral reasoning differ from each other in (...) Leibniz, and compare moral reasoning and instincts as sources of knowledge in his practical philosophy. As the practical instincts are closely related to pleasure and passions, which are by nature cognitive, my emphasis will be on the affective character of instinctive moral action and especially deliberation which leads to moral action. I will argue that inclinations arising from moral instinct, which lead us to pleasure while avoiding sorrow, can direct our moral action and sometimes anticipate reasoning when conclusions are not readily available. Acting by will, which is related to moral reasoning, and acting by instincts can lead us to the same moral knowledge independently, but they can also complement each other. To illustrate the two alternative ways to reach moral knowledge, I will discuss the case of happiness, which is the goal of all human moral action for Leibniz. (shrink)

Robert Aumann presents his Agreement Theorem as the key conditional: “if two people have the same priors and their posteriors for an event A are common knowledge, then these posteriors are equal” (Aumann, 1976, p. 1236). This paper focuses on four assumptions which are used in Aumann’s proof but are not explicit in the key conditional: (1) that agents commonly know, of some prior μ, that it is the common prior; (2) that agents commonly know that each (...) of them updates on the prior by conditionalization; (3) that agents commonly know that if an agent knows a proposition, she knows that she knows that proposition (the “K K” principle); (4) that agents commonly know that they each update only on true propositions. It is shown that natural weakenings of any one of these strong assumptions can lead to countermodels to Aumann’s key conditional. Examples are given in which agents who have a common prior and commonly know what probability they each assign to a proposition nevertheless assign that proposition unequal probabilities. To alter Aumann’s famous slogan: people can “agree to disagree”, even if they share a common prior. The epistemological significance of these examples is presented in terms of their role in a defense of the Uniqueness Thesis: If an agent whose total evidence is E is fully rational in taking doxastic attitude D to P, then necessarily, any subject with total evidence E who takes a different attitude to P is less than fully rational. (shrink)

In his famous 1982 paper, Allen Newell [22, 23] introduced the notion of knowledge level to indicate a level of analysis, and prediction, of the rational behavior of a cognitive arti cial agent. This analysis concerns the investigation about the availability of the agent knowledge, in order to pursue its own goals, and is based on the so-called Rationality Principle (an assumption according to which "an agent will use the knowledge it has of its environment to achieve (...) its goals" [22, p. 17]. By using the Newell's own words: "To treat a system at the knowledge level is to treat it as having some knowledge, some goals, and believing it will do whatever is within its power to attain its goals, in so far as its knowledge indicates" [22, p. 13]. In the last decades, the importance of the knowledge level has been historically and system- atically downsized by the research area in cognitive architectures (CAs), whose interests have been mainly focused on the analysis and the development of mechanisms and the processes governing human and (arti cial) cognition. The knowledge level in CAs, however, represents a crucial level of analysis for the development of such arti cial general systems and therefore deserves greater research attention [17]. In the following, we will discuss areas of broad agree- ment and outline the main problematic aspects that should be faced within a Common Model of Cognition [12]. Such aspects, departing from an analysis at the knowledge level, also clearly impact both lower (e.g. representational) and higher (e.g. social) levels. (shrink)

In her analysis of the politics of biotechnology, Sheila Jasanoff argued that modern democracy cannot be understood without an analysis of the ways knowledge is created and used in society. She suggested calling these ways to “know things in common” civic epistemologies. Jasanoff thus approached knowledge as fundamentally social. The focus on the social nature of knowledge allows drawing parallels with some developments in philosophy of science. In the first part of the paper, I juxtapose Jasanoff’s (...) account with the philosopher Helen Longino’s approach. Longino argued that objectivity of scientific knowledge is made possible by the social nature of knowledge production. In the process of community-wide discussion, claims that are not intersubjectively acceptable are rejected and communally acceptable knowledge emerges. Longino called this knowledge-creating critical dialogue transformative. I suggest that Longino’s account can be seen as providing epistemological support for the civic epistemologies Jasanoff described. They are capable of producing knowledge in the normative philosophical sense of the word to the degree that they are able to support this transformative critical dialogue. In the second part of the paper, I explore in the light of Longino’s criteria for effective knowledge-productive dialogue one of the controversies in biotechnology policy that Jasanoff analysed. I suggest that Longino’s criteria allow identifying some fundamental obstacles for initiating and maintaining this kind of responsive critical dialogue and that the controversy can be seen as caused by inability to overcome these obstacles. In such a case, the controversy signals an epistemic failure as well as a failure of democratic policy. (shrink)

EN In his “Logic, Language, and Knowledge” Chateaubriand denounces the tyranny of belief , but takes some positions on knowledge and justification which seem to be too exacting. The fact that Chateaubriand derives constraints on the notion of justification by a close parallel to the notion of proof makes it unnecessarily loaded with the individual, rather than with the collective perspective. His position seems to leave little room for common knowledge, collective knowledge and usual (...) class='Hi'>common-sense knowledge, and absolutely no room for explaining how people take correct decisions based on apparently faulty notions of knowledge and justification. -/- PT Em “Logic, Language, and Knowledge” Chateaubriand denuncia a tirania da crença , mas toma posições sobre conhecimento e justificação que parecem demasiado exigentes. O fato de Chateaubriand derivar condições sobre a noção de justificação a partir de uma estreita analogia com a noção de prova torna a noção de justiticação desnecessariamente carregada com a perspectiva indivídual, em detrimento da perspectiva coletiva. Sua posição parece deixar pouco espaço para noções como conhecimento comum, conhecimento coletivo e senso comum, e absolutamente nenhum espaço para explicar como as pessoas tomam decisões corretas com base em noções aparentemente errôneas de conhecimento e de justificação. (shrink)

It is commonly assumed that besides knowledge of facts or truths, there is also knowledge of things–for example, we say that we know people or know places. We could call this "objectual knowledge". In this paper, I raise doubts about the idea that there is a sui generis objectual knowledge that is distinct from knowledge of truths.

It is common orthodoxy among internalists and externalists alike that knowledge is lost or defeated in situations involving misleading evidence of a suitable kind. But making sense of defeat has seemed to present a particular challenge for those who reject an internalist justification condition on knowledge. My main aim here is to argue that externalists ought to take seriously a view on which knowledge can be retained even in the face of strong seemingly defeating evidence. As (...) an instructive example, I first discuss whether a theory on which knowledge is belief that is safe from error has the resources for accommodating defeat. I argue that beliefs retained in defeat cases need not be unsafe or true in some accidental way. I then discuss externalist strategies for explaining why we have incorrect intuitions about defeat. The notion of an epistemically reasonable subject plays a central role in my theory. Reasonable subjects adopt general strategies that are good for acquiring true belief and knowledge across a wide range of normal cases, but stubbornly retaining belief in the face of new evidence does not reflect such policies. I argue that though the methods employed by subjects who fail to adjust their beliefs in defeat cases may be perfectly good, they are not good methods to adopt, as their adoption is accompanied by bad dispositions. What emerges is a view on which a subject can know despite being unreasonable, and despite failing to manifest dispositions to know across normal cases. Unreasonable subjects are genuinely criticisable, but like almost anything, knowledge can sometimes be achieved in the absence of a good general strategy. (shrink)

In recent work on the semantics of ‘knowledge’-attributions, a variety of accounts have been proposed that aim to explain the data about speaker intuitions in familiar cases such as DeRose’s Bank Case or Cohen’s Airport Case by means of pragmatic mechanisms, notably Gricean implicatures. This paper argues that pragmatic explanations of the data regarding ‘knowledge’-attributions are unsuccessful and concludes that in explaining those data we have to resort to accounts that (a) take those data at their semantic face (...) value (Epistemic Contextualism, Subject-Sensitive Invariantism or Epistemic Relativism), or (b) reject them on psychological grounds (Moderate Insensitive Invariantism). To establish this conclusion, the paper relies solely upon widely accepted assumptions about pragmatic theory, broadly construed, and on the Stalnakerian insight that linguistic communication takes place against the backdrop of a set of mutually accepted propositions: a conversation’s common ground. (shrink)

We develop a conceptually clear, intuitive, and feasible decision procedure for testing satisfiability in the full multi\-agent epistemic logic \CMAELCD\ with operators for common and distributed knowledge for all coalitions of agents mentioned in the language. To that end, we introduce Hintikka structures for \CMAELCD\ and prove that satisfiability in such structures is equivalent to satisfiability in standard models. Using that result, we design an incremental tableau-building procedure that eventually constructs a satisfying Hintikka structure for every satisfiable input (...) set of formulae of \CMAELCD\ and closes for every unsatisfiable input set of formulae. (shrink)

kk states that knowing entails knowing that one knows, and K¬K states that not knowing entails knowing that one does not know. In light of the arguments against kk and K¬K⁠, one might consider modally qualified variants of those principles. According to weak kk, knowing entails the possibility of knowing that one knows. And according to weakK¬K⁠, not knowing entails the possibility of knowing that one does not know. This paper shows that weak kk and weakK¬K are much stronger than (...) they initially appear. Jointly, they entail kk and K¬K⁠. And they are susceptible to variants of the standard arguments against kk and K¬K⁠. This has interesting implications for the debate on positive introspection and for deeper issues concerning the structure and limits of knowability. (shrink)

We argue against the knowledge rule of assertion, and in favour of integrating the account of assertion more tightly with our best theories of evidence and action. We think that the knowledge rule has an incredible consequence when it comes to practical deliberation, that it can be right for a person to do something that she can't properly assert she can do. We develop some vignettes that show how this is possible, and how odd this consequence is. We (...) then argue that these vignettes point towards alternate rules that tie assertion to sufficient evidence-responsiveness or to proper action. These rules have many of the virtues that are commonly claimed for the knowledge rule, but lack the knowledge rule's problematic consequences when it comes to assertions about what to do. (shrink)

Could it be right to convict and punish defendants using only statistical evidence? In this paper, I argue that it is not and explain why it would be wrong. This is difficult to do because there is a powerful argument for thinking that we should convict and punish defendants using statistical evidence. It looks as if the relevant cases are cases of decision under risk and it seems we know what we should do in such cases (i.e., maximize expected value). (...) Given some standard assumptions about the values at stake, the case for convicting and punishing using statistical evidence seems solid. In trying to show where this argument goes wrong, I shall argue (against Lockeans, reliabilists, and others) that beliefs supported only by statistical evidence are epistemically defective and (against Enoch, Fisher, and Spectre) that these epistemic considerations should matter to the law. To solve the puzzle about the role of statistical evidence in the law, we need to revise some commonly held assumptions about epistemic value and defend the relevance of epistemology to this practical question. (shrink)

In this chapter, I first turn to Spinoza’s obscure “ideas of ideas” doctrine and his claim that “as soon as one knows something, one knows that one knows it, and simultaneously knows that one knows that one knows, and so on, to infinity” (E2p21s). On my view, Spinoza, like Descartes, holds that a given idea can be conceived either in terms of what it represents or as an act of thinking: E2p7 (where Spinoza presents his doctrine of the “parallelism” of (...) minds and bodies) primarily concerns the former way of conceiving of an idea while E2p21 primarily concerns the latter. I propose that in E2p21, Spinoza makes a few crucial points about an adequate idea conceived as the “idea of the idea,” or as the activity of thinking: 1) when one has an adequate representation of p, one automatically knows that one is thinking an adequate representation of p, and 2) this reflective knowledge cannot be improved. I then turn to E2p43, “he who has a true idea at the same time knows that he has a true idea, and cannot doubt the truth of the thing." This is a denial of skepticism, but I think we need to be careful. E2p21 and E2p43 rule out the most hyperbolic doubts like those we see in Descartes's Third Meditation (AT VII 36), so it is the case that thinkers need no additional validation for the “adequate ideas of properties of things” and “common notions” employed in "cognition of the second kind," or reason. However, a reasoning thinker might nevertheless be troubled by doubts about the extramental world. As I have argued in other work, we can take Spinoza as following Descartes at least this far: once our reasoning thinker comes to adequate ideas of God and God’s relation to things, their ideas cannot be rendered doubtful. Here I concede that because one can reason to these adequate ideas of God and God's relation to things, scientia intuitiva is not unique in removing doubt. However, scientia intuitiva may still be distinctive in the way it removes doubt. (shrink)

Hard to say what knowledge is. The more this concept is discussed, the more divergent opinions are. Epistemology is the theory of knowledge, and one of the characteristic questions of epistemology concerns what all the myriad kinds of knowledge we ascribe to ourselves have in common. A major distinction between different types of knowledge is descriptive, declarative, or propositional knowledge (which requires a greater degree of intellectual sophistication on the part of the knowledge (...) seeker) and knowledge or skill knowledge. For a description, statement, or assertion to be knowledge, it must be a belief, be true, and be justified. A statement of faith is an expression of belief in someone or something. Belief must be true to be knowledge. Plato, in the Gorgias, argues that faith is the most frequently invoked bearer of truth. In many of Plato's dialogues, such as the Meno and especially the Theaetetus, Socrates regards knowledge as true belief explained or defined in some way. Justification for belief involves a good reason for doing so. The definition of knowledge as justified true belief was widely accepted until 1960, when the American philosopher Edmund Gettier provoked major widespread discussion. -/- DOI: 10.13140/RG.2.2.11276.59528. (shrink)

We describe the three place relation of contrastive knowledge, which holds between a person, a target proposition, and a contrasting proposition. The person knows that p rather than that q. We argue for three claims about this relation. (a) Many common sense and philosophical ascriptions of knowledge can be understood in terms of it. (b) Its application is subject to fewer complications than non-contrastive knowledge is. (c) It applies over a wide range of human and nonhuman (...) cases. (shrink)

1. What is the relation between skilful action and knowledge? According to most philosophers, the two have little in common: practical intelligence and theoretical intelligence are largely separate...

A prominent objection to the knowledge norm of belief is that it is too demanding or too strong. The objection is commonly framed in terms of the idea that there is a tight connection between norm violation and the appropriateness of criticism or blame. In this paper I do two things. First, I argue that this way of motivating the objection leads to an impasse in the epistemic norms debate. It leads to an impasse when knowledge normers invoke (...) excuses to explain away a prima facie connection between blamelessness and justified belief. Second, I argue that a way out of the impasse becomes available when we take a closer look at some distinctions in the theory of responsibility. There are at least three different notions of responsibility relevant here. I argue that a weaker notion of responsibility – attributability – should be used to motivate the objection that the knowledge norm of belief is too strong. Insofar as the proposal motivates the objection without appeal to blamelessness, it opens up space to move beyond the impasse. (shrink)

Although the Greek language of the archaic period lacked nominative expressions equivalent to the English “knowledge”, Greek speakers and writers employed a number of verbs in speaking of those who fail or succeed in knowing some fact, truth, state of affairs, or area of expertise—most commonly eidenai, gignôskein, epistamai, sunienai, and noein (in its aorist forms). In the Homeric poems, knowledge can be attained either through direct observation, through a revelatory trial or testing procedure, or from the reliable (...) testimony of others (each of these approaches figures in the discovery of Odysseus’ identity). Three broad ‘epistemic sentiments’ pervade early Greek poetry: the inability of mortals to grasp the nature of things lying beyond their immediate experience; the inability of mortals to grasp the larger course of events or ‘conceiving of what lies ahead and behind’ (prossô kai opissô); and the ability of ‘gifted’ poets and seers to overcome these limitations by drawing upon divine sources of truth and wisdom. (shrink)

Diabetes is a major public health issue that affects the nations of our time to a large extent and is described as a non-communicable epidemic. Diabetes mellitus is a common disease where there is too much sugar (glucose) floating around in your blood. This occurs because either the pancreas can’t produce enough insulin or the cells in body have become resistant to insulin. The concentration in this paper is on diagnosis diabetes by designing a proposed expert system. The main (...) goal of this expert system is to get the appropriate diagnosing of the illness, dealing with it quickly, and tips for permanent treatment whenever possible is given out. SL5 object expert system language was used for designing and implementing the proposed expert system. (shrink)

Many philosophers think that common sense knowledge survives sophisticated philosophical proofs against it. Recently, however, Bryan Frances (forthcoming) has advanced a philosophical proof that he thinks common sense can’t survive. Exploiting philosophical paradoxes like the Sorites, Frances attempts to show how common sense leads to paradox and therefore that common sense methodology is unstable. In this paper, we show how Frances’s proof fails and then present Frances with a dilemma.

What is knowledge of one's own current, consciously entertained intentional states a form of inner awareness? If so, what form? In this paper I explore the prospects for a quasi-observational account of a certain class of cases where subjects appear to have self-knowledge, namely, the so-called cogito-like cases. In section one I provide a rationale for the claim that we need an epistemology of self-knowledge, and specifically, an epistemology of the cogito-like cases. In section two I argue (...) that contentful properties in such cases have two features in common with observational properties of objects. In section three, I develop a quasi-observational account of self-knowledge for the cogito-like cases by considering various accounts of the nature of observational properties and by applying them to these cases. I conclude by addressing some important objections to the account. (shrink)

The thesis that knowledge is a factive mental state plays a central role in knowledge-first epistemology, but accepting this thesis requires also accepting an unusually severe version of externalism about the mind. On this strong attitude externalism, whether S is in the mental state of knowledge can and often will rapidly change in virtue of changes in external states of reality with which S has no causal contact. It is commonly thought that this externalism requirement originates in (...) the factivity of knowledge. However, despite a number of recent defenses of non-factive accounts of knowledge, epistemology has yet to consider whether a non-factive approach might produce a version of the mental state thesis that can avoid strong externalism. Here I do just that, exploring how three different proposals for weakening factivity might be adapted to theories of knowledge as a non-factive mental state. Contrary to what we might expect, however, none of these proposals are compatible with anything close to attitude internalism about knowledge—or even a substantially weaker externalism. All told, the widespread view that wraps up the severe externalism required for knowledge to be a mental state in factivity is mistaken. Knowledge’s external-world connection runs far deeper than the factivity constraint. (shrink)

The internet has considerably changed epistemic practices in science as well as in everyday life. Apparently, this technology allows more and more people to get access to a huge amount of information. Some people even claim that the internet leads to a democratization of knowledge. In the following text, we will analyze this statement. In particular, we will focus on a potential change in epistemic structure. Does the internet change our common epistemic practice to rely on expert opinions? (...) Does it alter or even undermine the division of epistemic labor? The epistemological framework of our investigation is a naturalist-pragmatist approach to knowledge. We take it that the internet generates a new environment to which people seeking information must adapt. How can they, and how should they, expand their repertory of social markers to continue the venture of filtering, and so make use of the possibilities the internet apparently provides? To find answers to these questions we will take a closer look at two case studies. The first example is about the internet platform WikiLeaks that allows so-called whistle-blowers to anonymously distribute their information. The second case study is about the search engine Google and the problem of personalized searches. Both instances confront a knowledge-seeking individual with particular difficulties which are based on the apparent anonymity of the information distributor. Are there ways for the individual to cope with this problem and to make use of her social markers in this context nonetheless? (shrink)

This paper advocates a realist position with respect to science and common sense. It considers the question of whether science provides knowledge of reality. It presents a positive response to that question. It rejects the anti-realist claim that we are unable to acquire knowledge of reality in favour of the realist view that science yields knowledge of the external world. But it remains to be specified just what world that is. Some argue that science leads to (...) the rejection of our commonsense view of the world. If so, the world about which science informs us is not the world of common sense. Common sense is “stone-age metaphysics”. It is false theory inherited from our primitive ancestors that is to be eliminated in favour of science. Against such an elimination of common sense, it is argued that science both preserves and explains our commonsense experience of the world. Science may well lead to the overthrow of some of our most deeply held beliefs. But common sense reflects a more basic and durable level of experience. Commonsense beliefs are well-confirmed beliefs that are vindicated by their role in successful practical action each and every day. Common sense provides a firm basis on which to base a realist philosophy of science. (shrink)

The Common Paradox Resolution Argument presents a systematic approach to addressing some of philosophy’s most enduring paradoxes. By analyzing the logical structure and underlying assumptions of each paradox, this argument proposes unique resolutions that aim to preserve logical consistency while clarifying apparent contradictions. The argument covers well-known paradoxes, including the Liar’s Paradox, the Self-Reference Paradox, and the Complete Knowledge Paradox, among others, each of which is dissected and reinterpreted to reveal insights into language, truth, and self-reference. -/- This (...) approach leverages newly developed logical fallacies—such as the Arbitrary Restriction Fallacy and the Self-Reference Paradox Fallacy—created specifically to address the nuances within these paradoxes. The argument contends that by identifying and naming these fallacies, it becomes possible to resolve paradoxical scenarios by revealing flaws in their foundational premises. Ultimately, the Common Paradox Resolution Argument provides a robust framework for interpreting and resolving paradoxes, contributing to a clearer understanding of logical structures and enhancing philosophical discourse on fundamental questions of truth and self-consistency. (shrink)

The standard of disinterested objectivity embedded within the US Data Quality Act (2001) has been used by corporate and political interests as a way to limit the dissemination of scientific research results that conflict with their goals. This is an issue that philosophers of science can, and should, publicly address because it involves an evaluation of the strength and adequacy of evidence. Analysis of arguments from a philosophical tradition that defended a concept of useful knowledge (later displaced by Logical (...) Empiricism) is used here to suggest how the legitimacy of scientific findings can be supported in the absence of disinterested objectivity. (shrink)

What role does ‘ordinary language philosophy’ play in the defense of common sense beliefs? J.L. Austin and Ludwig Wittgenstein each give central place to ordinary language in their responses to skeptical challenges to common sense beliefs. But Austin and Wittgenstein do not always respond to such challenges in the same way, and their working methods are different. In this paper, I compare Austin’s and Wittgenstein’s metaphilosophical positions, and show that they share many metaphilosophical commitments. I then examine Austin (...) and Wittgenstein’s respective takes on the problem of other minds and the problem of our knowledge of the external world. Interestingly, we find Wittgenstein employing methods more frequently associated Austin and vice versa. Moreover, we find that a variety of defenses of common sense beliefs are compatible with ‘ordinary language philosophy.’. (shrink)

This paper aims to discuss the philosophical roles of common sense in Thomas Reid’s thought. I argue that there is not only one way of appealing to common sense in attempt of discovering truth and allowing knowledge. According to my understanding, Reid makes at least three distinct uses of common sense: (1) the foundational use, in which common sense is taken as the foundation upon which knowledge must be built; (2) the methodological use, in (...) which common sense arises as a source of methodo-logical presuppositions of philosophical investigations; (3) the instrumental use, in which common sense, in the light of the emotion of ridicule, is used as an instrument to refute philosophical principles and conclusions. (shrink)

I argue that knowledge is a particular kind of concept known as a thick concept. Examples of thick concepts include courage, generosity, loyalty, brutality, and so forth. These concepts are commonly said to combine both evaluation and description, and one of the main goals of this dissertation is to provide a new account of how a thick concept combines these elements. It is argued that thick concepts are semantically evaluative, and that they combine evaluation and description in a way (...) similar to that of concepts like good qua dancer and bad qua violinist. In the final chapter, this basic idea is applied to the concept of knowledge. There, the concept of knowledge is analyzed in terms of good qua belief. The upshot is that two central epistemological problems—the Gettier Problem and the Value Problem—can be resolved. (shrink)

In the literature on assertion, there is a common assumption that having the knowledge that p is a sufficient condition for having the epistemic right to assert that p—call this the Knowledge is Sufficient for Assertion Principle, or KSA. Jennifer Lackey has challenged KSA based on several counterexamples that all, roughly, involve isolated secondhand knowledge. In this article, I argue that Lackey’s counterexamples fail to be convincing because her intuition that the agent in her counterexamples both (...) has knowledge and do not have the epistemic right to assert is wrong. The article will progress as follows: In section 2, I present Lackey’s argument. In section 3, I suggest some more general reasons for doubting that the agent in her counterexamples actually has knowledge. I then show that from a virtue theoretic and Edward Craig’s practical explication of knowledge perspectives the agent in Lackey’ s counterexamples does not know. Since the agent in Lackey’s counterexamples does not have knowledge, she has failed to convincingly prove that KSA is false. In section 4, I conclude by suggesting that, at most, what Lackey’s counterexamples demonstrate is a problem with a simplistic evidentialist and/or process reliabilist epistemology. (shrink)

Scientific consensus is widely deferred to in public debates as a social indicator of the existence of knowledge. However, it is far from clear that such deference to consensus is always justified. The existence of agreement in a community of researchers is a contingent fact, and researchers may reach a consensus for all kinds of reasons, such as fighting a common foe or sharing a common bias. Scientific consensus, by itself, does not necessarily indicate the existence of (...) shared knowledge among the members of the consensus community. I address the question of under what conditions it is likely that a consensus is in fact knowledge based. I argue that a consensus is likely to be knowledge based when knowledge is the best explanation of the consensus, and I identify three conditions—social calibration, apparent consilience of evidence, and social diversity, for knowledge being the best explanation of a consensus. (shrink)

Doxastic normativism is the thesis that norms are constitutive of or essential to belief, such that no mental state not subject to those norms counts as a belief. A common normativist view is that belief is essentially governed by a norm of truth. According to Krister Bykvist and Anandi Hattiangadi, truth norms for belief cannot be formulated without unpalatable consequences: they are either false or they impose unsatisfiable requirements on believers. I propose that we construe the fundamental norm of (...) belief as a knowledge norm, rather than a truth norm. I argue that a specific kind of knowledge norm—one that has a subject's obligation to believe that p depend on her being in a position to know that p—might avoid the well-known formulation problems with truth norms. (shrink)

In this article I focus on some unduly neglected common-sense considerations supporting the view that one's evidence is the propositions that one knows. I reply to two recent objections to these considerations.

The view of nature we adopt in the natural attitude is determined by common sense, without which we could not survive. Classical physics is modelled on this common-sense view of nature, and uses mathematics to formalise our natural understanding of the causes and effects we observe in time and space when we select subsystems of nature for modelling. But in modern physics, we do not go beyond the realm of common sense by augmenting our knowledge of (...) what is going on in nature. Rather, we have measurements that we do not understand, so we know nothing about the ontology of what we measure. We help ourselves by using entities from mathematics, which we fully understand ontologically. But we have no ontology of the reality of modern physics; we have only what we can assert mathematically. In this paper, we describe the ontology of classical and modern physics against this background and show how it relates to the ontology of common sense and of mathematics. (shrink)

It is a commonly held view in contemporary epistemology that for having knowledge it is necessary to have an appropriately based belief, although numerous different views exist about when a belief’s base is appropriate. Broadly speaking, they all share the view that one can only have knowledge if the belief’s base is in some sense truth-related or tracking the truth. Baseless knowledge can then be defi ned as knowledge where the belief is acquired and sustained in (...) a way that does not track the truth. I will argue that rejecting baseless knowledge leads to controversial consequences. The problem increases if we consider contrasting persons who know because of appropriate belief forming processes but who fail to possess further epistemic virtues such as understanding. I will not argue which belief bases constitute a suffi cient condition for knowledge. Rather I will stress the point that the common assumption that an appropriate basing relation constitutes a necessary condition for knowledge has controversial consequences. (shrink)

Intentional action is, in some sense, non-accidental, and one common way action theorists have attempted to explain this is with reference to control. The idea, in short, is that intentional action implicates control, and control precludes accidentality. But in virtue of what, exactly, would exercising control over an action suffice to make it non-accidental in whatever sense is required for the action to be intentional? One interesting and prima facie plausible idea that we wish to explore in this paper (...) is that control is non-accidental in virtue of requiring knowledge – either knowledge-that or knowledge-how (e.g., Beddor and Pavese 2021; cf., Setiya 2008; 2012 and Habgood-Coote 2018). We review in detail some key recent work defending such knowledge-centric theories of control, and we show that none of these accounts holds water. We conclude with some discussion about how control opposes the sort of luck intentional action excludes without doing so by requiring knowledge (that- or how). (shrink)

I discuss several problems for Williamson’s counterfactual-theory of modal knowledge and argue that they have a common source, in that the theory neglects to elucidate the proper constraints on modal reasoning. Williamson puts forward an empirical hypothesis that rests on the role of counterfactual reasoning for modal knowledge. But he overlooks central questions of normative modal epistemology. In order for counterfactual reasoning to yield correct beliefs about modality, it needs to be suitably constrained. I argue that what (...) is needed is, specifically, information concerning the nature or essence of things. By integrating this information, essentialist deduction arguably provides a better account of our knowledge of modality. Furthermore, I argue that essences have distinctive causal and explanatory powers—indeed, essences are superexplanatory for how things are. Compared to Williamson’s counterfactual-theory, superexplanatory essentialism clarifies what the proper constraints on modal reasoning are, and why they have such a special status. (shrink)