I argue that Moore's propositions, for example, 'I went to the pictures last Tuesday but I don't believe that I did' cannot be rationally believed. Their assertors either cannot be rationally believed or cannot be believed to be rational. This analysis is extended to Moorean propositions such as God knows that I am an atheist and I believe that this proposition is false. I then defend the following definition of assertion: anyone asserts that p iff that person expresses a belief (...) that p with the intention of causing relevant epistemic change in the cognition of an actual or potential audience. (shrink)

ABSTRACT Timothy Williamson offers the ordinary practice, the lottery and the Moorean argument for the ‘knowledge account’ that assertion is the only speech-act that is governed by the single rule that one must know its content. I show that these fail to support it and that the emptiness of the knowledge account renders mysterious why breaking the knowledge rule should be a source of criticism. I argue that focussing exclusively on the sincerity of the speech-act of letting one know engenders (...) a category mistake about the nature of constraints on assertion. After giving an analysis of assertion I propose that the norm of a type of assertion is the epistemic state one needs for one’s speech-act to succeed in being an assertion of that type and that the epistemic state in question is determined by the point of the type of assertion. One is practically irrational in violating the norm. (shrink)

According to the subjective view of lying, speakers can lie by asserting a true proposition, as long as they believe this proposition to be false. This view contrasts with the objective view, according to which lying requires the actual falsity of the proposition asserted. The aim of this paper is to draw attention to pairs of assertions that differ only in intuitively redundant content and to show that such pairs of assertions are a reason to favour the subjective view of (...) lying over the objective one. (shrink)

Besides pure declarative arguments, whose premises and conclusions are declaratives, and pure imperative arguments, whose premises and conclusions are imperatives, there are mixed-premise arguments, whose premises include both imperatives and declaratives, and cross-species arguments, whose premises are declaratives and whose conclusions are imperatives or vice versa. I propose a general definition of argument validity: an argument is valid exactly if, necessarily, every fact that sustains its premises also sustains its conclusion, where a fact sustains an imperative exactly if it favors (...) the satisfaction over the violation proposition of the imperative, and a fact sustains a declarative exactly if, necessarily, the declarative is true if the fact exists. I argue that this definition yields as special cases the standard definition of validity for pure declarative arguments and my previously defended definition of validity for pure imperative arguments, and that it yields intuitively acceptable results for mixed-premise and cross-species arguments. (shrink)

Assertion is widely regarded as an act associated with an epistemic position. To assert is to represent oneself as occupying this position and/or to be required to occupy this position. Within this approach, the most common view is that assertion is strong: the associated position is knowledge or certainty. But recent challenges to this common view present new data that are argued to be better explained by assertion being weak. Old data widely taken to support assertion being strong has also (...) been challenged. This paper examines such challenges and finds them wanting. Far from diminishing the case for strong assertion, carefully considering new and old data reveals that assertion is as strong as ever. (shrink)

In this paper we present an extension of (bunched) separation logic, Boolean BI, with epistemic and dynamic epistemic modalities. This logic, called action model separation logic ( \(\mathrm {AMSL}\) ), can be seen as a generalization of public announcement separation logic in which we replace public announcements with action models. Then we not only model public information change (public announcements) but also non-public forms of information change, such as private announcements. In this context the semantics for the connectives \(*\) and (...) \(\mathrel {-*}\) from separation logic are epistemic versions of their usual semantics. This is because formulas are interpreted in states, not in resources, and agents may be uncertain between different states representing the same resource. We present the logic \(\mathrm {AMSL}\) and its semantics, with a detailed case study that highlights its interest for modeling. We also prove the elimination of the dynamics modalities and discuss some alternative epistemic semantics for the separation connectives. (shrink)

Why is it that philosophers find it so hard to come to agreement? Many disputes that have gone on for centuries or even millennia are still unresolved, even though there has been increased conceptual sophistication on the part of the contending parties. Consider, for example, the question of free will, where libertarians still contest the field with determinists and compatibilists.

In this paper, I take up the question of how epistemic injustices can be resisted. Miranda Fricker, who introduced the term to describe situations in which subjects are wronged as knowers, has initially advocated an individualist, virtue-based account to counteract epistemic injustices. Epistemic injustices, however, do not merely operate at an individual level but are rooted in social practices and structures. Arguably therefore, individually virtuous epistemic conduct is not enough to uproot patterns of epistemic injustice. Institutional change and collective actions (...) are needed. Recently, Elizabeth Anderson has proposed such a structural remedy. Diagnosing patterns of social segregation that track existing inequalities to be the principal structural cause of epistemic injustices, Anderson suggests that integration is required to achieve epistemic justice. Pace Anderson, I argue that certain segregated spaces —namely spaces provided by subaltern counter-publics— can function and, in fact, have historically functioned as important sites of epistemic resistance. In particular, I argue that even if integration is sharply distinguished from assimilation, Anderson’s proposal insufficiently acknowledges the subversive potential of those spaces, in which shielded from the gaze of the oppressors, marginally situated subjects can assemble and question hegemonic epistemic practices. (shrink)

Moore’s Paradox is a test case for any formal theory of belief. In Knowledge and Belief, Hintikka developed a multimodal logic for statements that express sentences containing the epistemic notions of knowledge and belief. His account purports to offer an explanation of the paradox. In this paper I argue that Hintikka’s interpretation of one of the doxastic operators is philosophically problematic and leads to an unnecessarily strong logical system. I offer a weaker alternative that captures in a more accurate way (...) our logical intuitions about the notion of belief without sacrificing the possibility of providing an explanation for problematic cases such as Moore’s Paradox. (shrink)

Given the prominent position Habermas' philosophy has gained, it is surprising that his method, rational reconstruction, has not caused more debate. This article clarifies what this method consists of, and shows how it is used in two of Habermas' research programs. The method is an interesting, but problematic way of confronting some of the basic epistemological questions in the social sciences. It represents an alternative to both the empirical-analytical and the hermeneutic tradition. On the basis of this methodology, Habermas' work (...) is situated between the transcendental and the empirical approach. A fundamental problem is that it remains unclear how to test the hypothesis put forward through rational reconstruction. (shrink)

Homoeopathy is commonly recognised as pseudoscience. However, there is, to date, no systematic discussion that seeks to establish this view. In this paper, we try to fill this gap. We explain the nature of homoeopathy, discuss the notion of pseudoscience, and provide illustrative examples from the literature indicating why homoeopathy fits the bill. Our argument contains a conceptual and an empirical part. In the conceptual part, we introduce the premise that a doctrine qualifies as a pseudoscience if, firstly, its proponents (...) claim scientific standing for it and, secondly, if they produce bullshit to defend it, such that, unlike science, it cannot be viewed as the most reliable knowledge on its topic. In the empirical part, we provide evidence that homoeopathy fulfils both criteria. The first is quickly established since homoeopaths often explicitly claim scientificity. To establish the second, we dive into the pseudo-academic literature on homoeopathy to provide evidence of bullshit in the arguments of homoeopaths. Specifically, we show that they make bizarre ontological claims incompatible with natural science, illegitimately shift the burden of proof to sceptics, and mischaracterise, cherry-pick, and misreport the evidence. Furthermore, we demonstrate that they reject essential parts of established scientific methodology and use epistemically unfair strategies to immunise their doctrine against recalcitrant evidence. (shrink)

What does 'might' mean? One hypothesis is that 'It might be raining' is essentially an avowal of ignorance like 'For all I know, it's raining'. But it turns out these two constructions embed in different ways, in particular as parts of larger constructions like Wittgenstein's 'It might be raining and it's not' and Moore's 'It's raining and I don't know it', respectively. A variety of approaches have been developed to account for those differences. All approaches agree that both Moore sentences (...) and Wittgenstein sentences are classically consistent. In this paper I argue against this consensus. I adduce a variety of new data which I argue can best be accounted for if we treat Wittgenstein sentences as being classically inconsistent. This creates a puzzle, since there is decisive reason to think that 'Might p' is classically consistent with 'Not p'. How can it also be that 'Might p and not p' and 'Not p and might p' are classically inconsistent? To make sense of this situation, I propose a new theory of epistemic modals and their interaction with embedding operators. This account makes sense of the subtle embedding behavior of epistemic modals, shedding new light on their meaning and, more broadly, the dynamics of information in natural language. -/- . (shrink)

By all indications, the popularity of the Sense-Datum Theory is definitely on the wane. This once-proud theory, which was perhaps the most characteristic feature of British Philosophy during the first half of this century, has been attacked from so many different sides that even its foremost protagonists have either accepted the very watered-down version according to which it is just an alternative language for speaking about the facts of perception or else they hold their peace and let the youngsters play. (...) There are still some diehards who carry on as if nothing had happened, but they are an insignificant minority. (shrink)

A true lie is a lie that becomes true when announced. In a logic of announcements, where the announcing agent is not modelled, a true lie is a formula that becomes true when announced. We investigate true lies and other types of interaction between announced formulas, their preconditions and their postconditions, in the setting of Gerbrandy’s logic of believed announcements, wherein agents may have or obtain incorrect beliefs. Our results are on the satisfiability and validity of instantiations of these semantically (...) defined categories, on iterated announcements, including arbitrarily often iterated announcements, and on syntactic characterization. We close with results for iterated announcements in the logic of knowledge, and for lying as private announcements to different agents. Detailed examples illustrate our lying concepts. (shrink)

Contingency and accident are two important notions in philosophy and philosophical logic. Their meanings are so close that they are mixed up sometimes, in both daily life and academic research. This indicates that it is necessary to study them in a unified framework. However, there has been no logical research on them together. In this paper, we propose a language of a bimodal logic with these two concepts, investigate its model-theoretical properties such as expressivity and frame definability. We axiomatize this (...) logic over various classes of frames, whose completeness proofs are shown with the help of a crucial schema. The interactions between contingency and accident can sharpen our understanding of both notions. Then we extend the logic to a dynamic case: public announcements. By finding the required reduction axioms, we obtain a complete axiomatization, which gives us a good application to Moore sentences. (shrink)

Hobbes's central insight about ethics was that it should not be understood to require that we make ourselves a prey for others. It is this insight that both varieties of contractarianism [Hobbesian and Kantian] respect. Consider a relationship between two human beings that exists for reasons of either love or duty; let us also suppose that it is a relationship that can be instrumentally valuable to both parties. In order for that relationship to receive our full moral endorsement, we must (...) ask whether either party uses the duty or the love connecting them in a way that affects the other party's ability to realize the instrumental value from that relationship. To be sure, good marriages and good friendships ought not to be centrally concerned with the question of justice, but they must also be, at the very least, relationships in which love or duty are not manipulated by either party in order to use the other party to her detriment. (shrink)

It is generally accepted that Popper‘s degree of corroboration, though “inductivist” in a very general and weak sense, is not inductivist in a strong sense, i.e. when by ‘inductivism’ we mean the thesis that the right measure of evidential support has a probabilistic character. The aim of this paper is to challenge this common view by arguing that Popper can be regarded as an inductivist, not only in the weak broad sense but also in a narrower, probabilistic sense. In section (...) 2, first, I begin by briefly characterizing the relevant notion of inductivism that is at stake here; second, I present and discuss the main Popperian argument against it and show that in the only reading in which the argument is formally it is restricted to cases of predicted evidence, and that even if restricted in this way the argument is formally valid it is nevertheless materially unsound. In section 3, I analyze the desiderata that, according to Popper, any acceptable measure for evidential support must satisfy, I clean away its ad-hoc components and show that all the remaining desiderata are satisfied by inductuvist-in-strict-sense measures. In section 4 I demonstrate that two of these desiderata, accepted by Popper, imply that in cases of predicted evidence any measure that satisfies them is qualitatively indistinguishable from conditional probability. Finally I defend that this amounts to a kind of strong inductivism that enters into conflict with Popper’s anti-inductivist argument and declarations, and that this conflict does not depend on the incremental versus non-incremental distinction for evidential-support measures, making Popper’s position inconsistent in any reading.Keywords: Popper; Inductivism; Confirmation; Corroboration. (shrink)

Baltag, Moss, and Solecki proposed an expansion of classical modal logic, called logic of epistemic actions and knowledge (EAK), in which one can reason about knowledge and change of knowledge. Kurz and Palmigiano showed how duality theory provides a flexible framework for modeling such epistemic changes, allowing one to develop dynamic epistemic logics on a weaker propositional basis than classical logic (for example an intuitionistic basis). In this paper we show how the techniques of Kurz and Palmigiano can be further (...) extended to define and axiomatize a bilattice logic of epistemic actions and knowledge (BEAK). Our propositional basis is a modal expansion of the well-known four-valued logic of Belnap and Dunn, which is a system designed for handling inconsistent as well as potentially conflicting information. These features, we believe, make our framework particularly promising from a computer science perspective. (shrink)

This book provides the first comprehensive account of Hume’s conception of objects in Book I of the Treatise. What, according to Hume, are objects? Ideas? Impressions? Mind-independent objects? All three? None of the above? Through a close textual analysis, I show that Hume thought that objects are imagined ideas. However, I argue that he struggled with two accounts of how and when we imagine such ideas. On the one hand, Hume believed that we always and universally imagine that objects are (...) the causes of our perceptions. On the other hand, he thought that we only imagine such causes when we reach a “philosophical” level of thought. This tension manifests itself in Hume’s account of personal identity; a tension that, I argue, Hume acknowledges in the Appendix to the Treatise. As a result of presenting a detailed account of Hume’s conception of objects, we are forced to accommodate new interpretations of, at least, Hume’s notions of belief, personal identity, justification and causality. (shrink)