I aim to illustrate how the recommender systems of digital platforms create a particularly problematic kind of vulnerability in their users. Specifically, through theories of scaffolded cognition and scaffolded affectivity, I argue that a digital platform’s recommender system is a cognitive and affective artifact that fulfills different functions for the platform’s users and its designers. While it acts as a content provider and facilitator of cognitive, affective and decision-making processes for users, it also provides a continuous and detailed amount of (...) information to platform designers regarding users’ cognitive and affective processes. This dynamic, I argue, engenders a kind of vulnerability in platform users, structuring a power imbalance between designers and users. This occurs because the recommender system can not only gather data on users’ cognitive and affective processes, but also affects them in an unprecedentedly economic and capillary manner. By examining one instance of ethically problematic practice from Facebook, I specifically argue that rather than being a tool for manipulating or exploiting people, digital platforms, especially by their underlying recommender systems, can single out and tamper with specific cognitive and affective processes as a tool specifically designed for mind invasion. I conclude by reflecting how the understanding of such AI systems as tools for mind invasion highlights some merits and shortcomings of the AI Act with regards to the protection of vulnerable people. (shrink)

In this paper, we will re-elaborate the notions of filter bubble and of echo chamber by considering human cognitive systems’ limitations in everyday interactions and how they experience digital technologies. Researchers who applied the concept of filter bubble and echo chambers in empirical investigations see them as forms of algorithmically-caused systems that seclude the users of digital technologies from viewpoints and opinions that oppose theirs. However, a significant majority of empirical research has shown that users do find and interact with (...) opposing views. Furthermore, we argue that the notion of filter bubble overestimates the social impact of digital technologies in explaining social and political developments without considering the not-only-technological circumstances of online behavior and interaction. This provides us with motivation to reconsider this notion’s validity and re-elaborate it in light of existing epistemological theories that deal with the discomfort people experience when dealing with what they do not know. Therefore, we will survey a series of philosophical reflections regarding the epistemic limitations of human cognitive systems. In particular, we will discuss how knowledge and mere belief are phenomenologically indistinguishable and how people’s experience of having their beliefs challenged is cause of epistemic discomfort. We will then go on to argue, in contrast with Pariser’s assumptions, that digital media users might tend to conform to their held viewpoints because of the “immediate” way they experience opposing viewpoints. Since online people experience others and their viewpoints as material features of digital environments, we maintain that this modality of confronting oneself with contrasting opinions prompts users to reinforce their preexisting beliefs and attitudes. (shrink)

Joint action among human beings is characterized by using elaborate cognitive feats, such as representing the mental states of others about a certain state of affairs. It is still debated how these capacities evolved in the hominid lineage. I suggest that the consolidation of a shared practice over time can foster the predictability of other’s behavior. This might facilitate the evolutionary passage from inferring what others might know by simply seeing them and what they are viewing towards a mutual awareness (...) of each other’s beliefs. I will examine the case for cooperative hunting in one chimpanzee community and argue that it is evidence that they have the potential to achieve common ground, suggesting that the consolidation of a practice might have supported the evolution of higher social cognition in the hominid lineage. (shrink)

Dispositionalism is the theory of modality according to which all (metaphysical and natural) modal truths are made true by some actual irreducibly dispositional property. The relationship between Dispositionalism and time is yet to be satisfactorily explored. In this paper we contribute to this task by examining how Dispositionalism deals with ‘dated truths’: propositions involving a specific time, e.g. “It might rain at 12.30”. We examine two possible accounts: the first, 'Dated Manifestations Strategy', is the idea that powers are very fine-grained, (...) and tend towards temporally very specific manifestations. We argue that such strategy should not be adopted, for it leads to unnecessary violations of ontological parsimony; it is unable to accommodate an ontology of platonic universals; and it is incapable of offering a principled explanation of the forward-looking nature of powers. We offer an alternative account, the "Duration Strategy", which relies on an independently determined arrow of time and the existence of some “duration facts” that specify how long a power takes to bring about its manifestation. We argue that the Duration Strategy is to be preferred. We then flesh out the account by exploring the connection between powers, duration facts, and processes. (shrink)

A lot of attention has recently been devoted to the notion of Trustworthy AI (TAI). However, the very applicability of the notions of trust and trustworthiness to AI systems has been called into question. A purely epistemic account of trust can hardly ground the distinction between trustworthy and merely reliable AI, while it has been argued that insisting on the importance of the trustee’s motivations and goodwill makes the notion of TAI a categorical error. After providing an overview of the (...) debate, we contend that the prevailing views on trust and AI fail to account for the ethically relevant and value-laden aspects of the design and use of AI systems, and we propose an understanding of the notion of TAI that explicitly aims at capturing these aspects. The problems involved in applying trust and trustworthiness to AI systems are overcome by keeping apart trust in AI systems and interpersonal trust. These notions share a conceptual core but should be treated as distinct ones. (shrink)

In this paper I address issues related to the problem of future contingents and the metaphysical doctrine of fatalism. Two classical responses to the problem of future contingents are the third truth value view and the all-false view. According to the former, future contingents take a third truth value which goes beyond truth and falsity. According to the latter, they are all false. I here illustrate and discuss two ways to respectively argue for those two views. Both ways are similar (...) in spirit and intimately connected with fatalism, in the sense that they engage with the doctrine of fatalism and accept a large part of a standard fatalistic machinery. (shrink)

The main purpose of this exploratory analysis is to understand whether, based on evidence gathered from international best practices selected among corporations which adopt the Global Reporting Initiative guidelines in sustainability reporting (SR), stakeholders are significantly consulted and involved—as international literature would indicate—by assurance providers, during assurance processes of SR. We aim at verifying if this practice—known as stakeholder assurance—is in fact widespread in SR assurance by carrying out empirical research, through content analysis, into a sample of 161 assurance statements (...) of international corporations, in order to test characteristics of any stakeholder assurance implemented. (shrink)

The goal of this paper is to defend the general tenet that time travelers cannot change the past within B-theoretical models of time, independently of how many temporal dimensions there are. Baron Pacific Philosophical Quarterly, 98, 129–147 offered a strong argument intended to reach this general conclusion. However, his argument does not cover a peculiar case, i.e. a B-theoretical one-dimensional model of time that allows for the presence of internal times. Loss Pacific Philosophical Quarterly, 96, 1–11 used the latter model (...) to argue that time travelers can change the past within such model. We show a way to debunk Loss’s argument, so that the general tenet about the impossibility of changing the past within B-theoretical models is maintained. (shrink)

When we witness a great actor, musician, or sportsperson performing, we share something of their experience. Only recently has it become clear just how this sharing of experience is realised within the human brain. 'Mirrors in the brain' provides an accessible overview of mirror neurons, written by the man who first discovered them.

Vetter (2015) develops a localised theory of modality, based on potentialities of actual objects. Two factors play a key role in its appeal: its commitment to Hardcore Actualism, and to Naturalism. Vetter’s commitment to Naturalism is in part manifested in her adoption of Aristotelian universals. In this paper, we argue that a puzzle concerning the identity of unmanifested potentialities cannot be solved with an Aristotelian conception of properties. After introducing the puzzle, we examine Vetter’s attempt at amending the Aristotelian conception (...) in a way that avoids the puzzle, and conclude that this amended version is no longer to be considered naturalistic. Potentiality theory cannot be both actualist and naturalist. We then argue that, if naturalism is to be abandoned by the actualist, there are good reasons to adopt a Platonist conception of universals, for they offer a number of theoretical advantages and allow us to avoid some of the problems facing Vetter’s theory. (shrink)

In this paper I argue that even the most radical metaphysics of powers (such as that adopted by Mumford & Anjum, Cartwright, or Groff) are compatible with eternalism. I first offer a taxonomy of powers ontologies, and attempt to characterise the difference between moderate and radical powers ontologies – the latter are characterised by an emphasis on production and dynamicity. I consider an argument by C. Friebe to the effect that the productive character of powers is inconsistent with Eternalism and (...) find it wanting. I then elucidate the notion of dynamicity that radical powers theorists employ by making apparent their link with an ontology of irreducible processes. Finally, I respond to an argument by Donatella Donati to the effect that eternalism entails a reductive account of change which is inconsistent with process ontologies, and show that the the two are compatible. I conclude that we have no reason to think that radical powers metaphysics (and, a fortiori, every powers ontology) are not compatible with eternalism. (shrink)

This paper develops a novel theory of the meaning of moral equality. This theory has two original and significant implications: first, it shows—contra what is commonly held in the literature—that adults and children are not always each other’s equals; rather, the former are sometimes inferior and sometimes superior to the latter, depending on the interest at stake. Second, it reveals that human beings’ comparative moral status changes across time, and what matters is that they are each other’s equals at simultaneous (...) segments of their lives. (shrink)

While growing empirical evidence suggests a continuity between human and non-human psychology, many philosophers still think that only humans can act and form beliefs rationally. In this paper, we challenge this claim. We first clarify the notion of rationality. We then focus on the rationality of beliefs and argue that, in the relevant sense, humans are not the only rational animals. We do so by first distinguishing between unreflective and reflective responsiveness to epistemic reasons in belief formation and revision. We (...) argue that unreflective responsiveness is clearly within the reach of many animals. We then defend that a key demonstration of reflective responsiveness would be the ability to respond to undermining defeaters. We end by presenting some empirical evidence that suggests that some animal species are capable of processing these defeaters, which would entail that even by the strictest standards, humans are not the only rational animals. (shrink)

Establishing Dispositionalism as a viable theory of modality requires the successful fulfilment of two tasks: showing that all modal truths can be derived from truths about actual powers, and offering a suitable metaphysics of powers. These two tasks are intertwined: difficulties in one can affect the chances of success in the other. In this paper, I generalise an objection to Dispositionalism by Jessica Leech and argue that the theory in its present form is ill-suited to account for de re truths (...) about merely possible entities. I argue that such difficulty is rooted in a problem in the metaphysics of powers. In particular, I contend that the well-known tension between two key principle of powers ontology, namely Directedness and Independence has received an unsatisfactory solution so far, and that it is this unsatisfactory solution concerning the status of “unmanifested manifestations” that makes it hard for Dispositionalism to account for mere possibilia. I develop a novel account of the status of unmanifested manifestations and an overall metaphysics of powers which allows to better respond to Leech's objection and handle mere possibilia. The central idea of the proposal is that unmanifested manifestations are akin to mere logical existents, and are best characterised as non-essentially non-located entities. (shrink)

Taking the inspiration from some points made by Scott Sturgeon and Albert Casullo, I articulate a view according to which an important difference between undermining and overriding defeaters is that the former require the subject to engage in some higher-order epistemic thinking, while the latter don’t. With the help of some examples, I argue that underminers push the cognizer to reflect on the way she formed a belief by challenging the epistemic worthiness of either the source of justification or the (...) specific justificatory process. By contrast, overriders needn’t pose any such challenge. I also consider some problems for the proposed view, and I put forward some possible solutions. Finally, I provide some details on how undermining defeat works in different cases. (shrink)

There is a tension between Dispositionalism––the view that all metaphysical modality is grounded in actual irreducible dispositional properties––and the possibility of time travel. This is due to the fact that Dispositionalism makes it much harder to solve a potentiality-based version of the grandfather paradox. We first present a potentiality-based version of the grandfather paradox, stating that the following theses are inconsistent: 1) time travel is possible, 2) powers fully ground modality, 3) self-defeating actions are impossible, 4) time-travellers retain their intrinsic (...) powers upon time-travelling, and 5) time-travellers are ordinary agents with basic intrinsic potentialities. We then consider a number of potential solutions, and find them wanting. We argue that the metaphysical impossibility of performing a self-defeating action acts as a necessary perfect mask––while time-travel lets us “slip” the potentiality under the mask, thus generating the contradiction. We conclude considering what are the options for the dispositionalist. (shrink)

Establishing Dispositionalism as a viable theory of modality requires the successful fulfilment of two tasks: (i) showing that all modal truths can be derived from truths about actual powers, and (ii) offering a suitable metaphysics of powers. These two tasks are intertwined: difficulties in one can affect the chances of success in the other. In this paper, I generalise an objection to Dispositionalism by Jessica Leech and argue that the theory in its present form is ill-suited to account for de (...) re truths about merely possible entities. I argue that such difficulty is rooted in a problem in the metaphysics of powers. In particular, I contend that the well-known tension between two key principle of powers ontology, namely Directedness (all powers are “for” their manifestation) and Independence (some powers might fail to bring about their manifestation) has received an unsatisfactory solution so far, and that it is this unsatisfactory solution concerning the status of “unmanifested manifestations” that makes it hard for Dispositionalism to account for mere possibilia. I develop a novel account of the status of unmanifested manifestations and an overall metaphysics of powers which allows to better respond to Leech's objection and handle mere possibilia. The central idea of the proposal is that unmanifested manifestations are akin to mere logical existents, and are best characterised as non-essentially non-located entities. (shrink)

Business Ethics, the Environment &Responsibility, Volume 31, Issue 3, Page 875-887, July 2022.

In this paper I argue that even the most radical metaphysics of powers (such as that adopted by Mumford and Anjum, Cartwright, or Groff) are compatible with eternalism. I first offer a taxonomy of powers ontologies, and attempt to characterise the difference between moderate and radical powers ontologies—the latter are characterised by an emphasis on _production_ and _dynamicity_. I consider an argument by C. Friebe to the effect that the productive character of powers is inconsistent with Eternalism and find it (...) wanting. I then elucidate the notion of _dynamicity_ that radical powers theorists employ by making apparent their link with an ontology of irreducible processes. Finally, I respond to an argument by Donatella Donati to the effect that eternalism entails a reductive account of change which is inconsistent with process ontologies, and show that the the two are compatible. I conclude that we have no reason to think that radical powers metaphysics (and, a fortiori, every powers ontology) are not compatible with eternalism. (shrink)

The notion of perfect recall in extensive games was introduced by Kuhn (1953), who interpreted it as "equivalent to the assertion that each player is allowed by the rules of the game to remember everything he knew at previous moves and all of his choices at those moves''. We provide a characterization and axiomatization of perfect recall based on two notions of memory: (1) memory of past knowledge and (2) memory of past actions.

Famously, Kripke has argued that the central portion of the Philosophical Investigations describes both a skeptical paradox and its skeptical solution. Solving the paradox involves the element of the community, which determines correctness conditions for rule-following behavior. What do such conditions precisely consist of? Is it accurate to say that there is no fact to the matter of rule following? How are the correctness conditions sustained in the community? My answers to these questions revolve around the idea that a rule (...) is followed insofar as a convention is in place. In particular, I consider the game-theoretic definition of convention offered by David Lewis and I show that it illuminates essential aspects of the communitarian understanding of rule-following. Make the following experiment: say “It’s cold here” and mean “It’s warm here”. Can you do it?Ludwig Wittgenstein, Philosophical Investigations, 1953, §510.I can’t say “it’s cold here” and mean “it’s warm here”—at least, not without a little help from my friends.David Lewis, Convention. (shrink)

We consider strategic-form games with ordinal payoffs and provide a syntactic analysis of common belief/knowledge of rationality, which we define axiomatically. Two axioms are considered. The first says that a player is irrational if she chooses a particular strategy while believing that another strategy is better. We show that common belief of this weak notion of rationality characterizes the iterated deletion of pure strategies that are strictly dominated by pure strategies. The second axiom says that a player is irrational if (...) she chooses a particular strategy while believing that a different strategy is at least as good and she considers it possible that this alternative strategy is actually better than the chosen one. We show that common knowledge of this stronger notion of rationality characterizes the restriction to pure strategies of the iterated deletion procedure introduced by Stalnaker (1994). Frame characterization results are also provided. (shrink)

For the past 20 years or so the literature on noncooperative games has been centered on the search for an equilibrium concept that expresses the notion of rational behavior in interactive situations. A basic tenet in this literature is that if a “rational solution” exists, it must be a Nash equilibrium. The consensus view, however, is that not all Nash equilibria can be accepted as rational solutions. Consider, for example, the game of Figure 1.

In this paper we examine whether and how powers ontologies can back formal causation. We attempt to answer three questions: i) what is formal causation; ii) whether we need formal causation, and iii) whether formal causation need powers and whether it can be grounded in powers. We take formal causal explanations to be explanations in which something's essence features prominently in the explanans. Three kinds of essential explanations are distinguished: constitutive, consequential, and those singling out something's propria. This last kind (...) of explanation has been somewhat overlooked in the literature, but we argue that it features in much of the most relevant uses of formal explanations in philosophy and science. These are the explanations for why an object has certain propertis that are not, properly speaking, parts of its essence, but that belong to it more intimately than just being part of its consequential essence: they are the properties that ‘flow’ from something's essence. It is argued that a powers metaphysics is uniquely placed to make sense of this last phenomenon. We then distinguish three grades of involvement in which powers might be salient for formal causal explanations: i) powers might be the subject matter of the essence operator, ii) the essence of something might include (or be exhausted) by powers, or iii) powers can explain how propria can flow from something's constitutive existence. (shrink)

This paper investigates the epistemic assumptions that David Lewis makes in his account of social conventions. In particular, I focus on the assumption that the agents have common knowledge of the convention to which they are parties. While evolutionary analyses show that the common knowledge assumption is unnecessary in certain classes of games, Lewis’ original account (and, more recently, Cubitt and Sugden’s reconstruction) stresses the importance of including it in the definition of convention. I discuss arguments pro et contra to (...) argue that, although the assumption might be relevant to a descriptively adequate account of social convention, it is not required for its rational reconstruction. I then point out that Lewis’ account, properly speaking, is of common reason to believe, rather than of common knowledge, and argue that, in order to formalize aptly the distinction between reason to believe and belief, standard formal epistemic models need to be supplemented with so-called awareness structures. Finally, I stress that the notion of knowledge implicit in Lewis’ text involves interesting elements that cannot be captured in the standard propositional formalizations, but need the full expressive force of quantified epistemic logic. (shrink)

Standard liberal theories of justice rest on the assumption that only those beings that hold the capacity for moral personality have moral status and therefore are right-holders. As many pointed out, this has the disturbing implication of excluding a wide range of entities from the scope of justice. Call this the under-inclusiveness objection. This paper provides a response to the under-inclusiveness objection and illustrates its implications for liberal theories of justice. In particular, the paper defends two claims: first, it argues (...) that both the CMP and the potential capacity for moral personality are bases of moral status. This pluralist account of the basis of moral status can broaden the scope of justice and provide a solid philosophical justification for the common-sense intuition that almost all human beings have a moral status that is different and superior to that of nonhuman animals. Second, contra what is commonly suggested, it contends that potential and actual moral persons have different and unequal rights, other things being equal. (shrink)

The question of the basis of human equality has recently gained increasing attention. However, much of the literature has focused on whether persons—understood as fully competent adults—have equal moral status, while relatively less attention has been devoted to the analysis of what grounds the equal moral status of those human beings who are not fully competent adults. This paper contributes to this debate by addressing the question of the equality of moral status between adults and children. Specifically, this paper has (...) three aims. First, it provides a conceptual map of this complex issue. Second, it argues that the challenges that have been raised against standard accounts of persons’ equal moral status are even more forceful when applied to the question of adults and children’s moral equality. Finally, it examines what a commitment to adults and children’s moral _inequality_ entails and what it does not, thereby showing that the justificatory role of the principle of moral equality is not as far-reaching as commonly assumed. (shrink)

Hardly anyone denies that (nearly) all human beings have equal moral status and therefore should be considered and treated as equals. Yet, if humans possess the property that confers moral status upon them to an unequal degree, how come they should be considered and treated as equals? It has been argued that this is because the variations in the degree to which the status‐conferring property is held above a relevant threshold are contingencies that do not generate differences in degrees of (...) moral status. Call this the contingency argument for the basis of moral equality. In this paper, I reject the contingency argument. Instead, I develop an attitude‐based account of the basis of moral equality: according to this account, the basis of moral equality lies in a fitting, basic, and independent moral attitude which is owed to human beings qua moral status‐holders, and provides a coherent and plausible explanation for why the variations above the threshold for moral status do not matter. (shrink)

The philosophy of language of Robert Brandom is based on a theoretical structure composed of three main elements: the normative analysis of linguistic practices, the inferential characterization of conceptual contents and the expressive articulation of the relations between the former two. Normative pragmatics aims to explain how linguistic practices are sufficient to confer contentful states in those who engage in them. Inferential semantics provides a theory of such pragmatic significances in terms of the inferential relations that articulate conceptual contents. Rational (...) expressivism is the thesis that concept application is essentially a process of turning something that can only be done into something that can also be said. Such a threefold structure is the core of normative inferentialism. This book is a concise, selfcontained and comprehensive presentation of this philosophical enterprise. It guides the reader through the analysis of Brandom’s imposing theoretical apparatus, the discovery of the roots of his approach in American pragmatism and German idealism, till the exploration of some of its most interesting and recent outcomes in pragmatics and semantics. It is a valuable resource for both those who approach Brandom’s work for the first time and those who are interested in the potential of normative inferentialism. (shrink)

The future is different from the past. What is past is fixed and set in stone. The future, on the other hand, is open insofar as it holds numerous possibilities. Branching-tree models of time account for this asymmetry by positing an ontological difference between the past and the future. Given a time t, a unique unified past lies behind t, whereas multiple alternative existing futures lie ahead of t. My goal in this paper is to show that there is an (...) incompatibility between the way branching-tree models account for the open future and the possibility of time travel. That is, I argue that once time travel enters the picture, branching time fails to model the openness of the future by means of alternative future branches. I show how this holds independently of whether branching-time models are cashed out in A-theoretic or B-theoretic terms. (shrink)

This paper introduces a new kind of explanation that we describe as ‘purely theoretical’. We first present an example, E, of what we take to be a case of purely theoretical explanation. We then show that the explanation we have in mind does not fit neatly into any of the existing categories of explanation. We take this to give us prima facie motivation for thinking that purely theoretical explanation is a distinctive kind of explanation. We then argue that it can (...) earn its keep via application to two existing literatures: the literature on how we explain the truth of true negative existential propositions and the literature on how we explain the truth of true propositions about the past. We reply to some possible concerns regarding the introduction of purely theoretical explanations. We conclude that there is nothing obviously wrong with them and explore the ramifications for particular debates in metaphysics. (shrink)

The principle of moral equality is one of the cornerstones of any liberal theory of justice. It is usually assumed that persons’ equal moral status should be grounded in the equal possession of a status-conferring property. Call this the property-first approach to the basis of moral equality. This approach, however, faces some well-known difficulties: in particular, it is difficult to see how the possession of a scalar property can account for persons’ equal moral status. A plausible way of circumventing such (...) difficulties is to explore another avenue for the justification of persons’ equal moral status: moral equality should be grounded in the wrongness of treating others as inferiors. Call this the relation-first approach to the basis of moral equality. This paper aims at providing some reasons as to why this approach should be rejected and clarifying why the property-first approach still represents the most promising way of justifying our commitment to moral equality. Two objections will be pressed against the relation-first approach: first, grounding moral equality in the wrongness of treating others as inferiors gives rise to some disturbing normative implications; second, relation-first accounts cannot vindicate the idea that a range of beings has equal fundamental rights. This, however, is precisely what an account of moral equality is meant to justify. The paper, then, concludes that the relation-first approach fails to provide a plausible answer to the question of the basis of moral equality. Property-first accounts, whatever problems they encounter, are still more viable in principle. (shrink)

This paper suggests a way of formalizing the amount of information that can be conveyed to each player along every possible play of an extensive game. The information given to each player i when the play of the game reaches node x is expressed as a subset of the set of terminal nodes. Two definitions are put forward, one expressing the minimum amount of information and the other the maximum amount of information that can be conveyed without violating the constraint (...) represented by the information sets. Our definitions provide intuitive characterizations of such notions as perfect recall, perfect information and simultanetty. (shrink)

Among the many possible approaches to dealing with logical omniscience, I consider here awareness and impossible worlds structures. The former approach, pioneered by Fagin and Halpern, distinguishes between implicit and explicit knowledge, and avoids logical omniscience with respect to explicit knowledge. The latter, developed by Rantala and by Hintikka, allows for the existence of logically impossible worlds to which the agents are taken to have access; since such worlds need not behave consistently, the agents’ knowledge is fallible relative to logical (...) omniscience. The two approaches are known to be equally expressive in propositional systems interpreted over Kripke semantics. In this paper I show that the two approaches are equally expressive in propositional systems interpreted over Montague-Scott (neighborhood) semantics. Furthermore, I provide predicate systems of both awareness and impossible worlds structures interpreted on neighborhood semantics and prove the two systems to be equally expressive. (shrink)

While the sociality of software agents drives toward the definition of institutions for multi agent systems, their autonomy requires that such institutions are ruled by appropriate norm mechanisms. Computational institutions represent useful abstractions. In this paper we show how computational institutions can be built on top of the RoleX infrastructure, a role-based system with interesting features for our aim. We achieve a twofold goal: on the one hand, we give concreteness to the institution abstractions; on the other hand, we demonstrate (...) the flexibility of the RoleX infrastructure. (shrink)

The logic of common belief does not always reflect that of individual beliefs. In particular, even when the individual belief operators satisfy the KD45 logic, the common belief operator may fail to satisfy axiom 5. That is, it can happen that neither is A commonly believed nor is it common belief that A is not commonly believed. We identify the intersubjective restrictions on individual beliefs that are incorporated in axiom 5 for common belief.

One important distinction in the debate over the nature of epistemic justification is the one between propositional and doxastic justification. Roughly, while doxastic justification is a property of beliefs, propositional justification is a property of propositions. On a rather common view, which accounts for doxastic justification in terms of propositional justification plus the so-called ‘basing relation’, propositional justification is seen as the prior notion, and doxastic justification is explained in terms of it. According to the opposing view, the direction of (...) explanation needs to be reversed, and doxastic justification should be seen as primary. I distinguish between two notions of priority, and I argue that they give different verdicts with respect to the issue of which notion of justification comes first. The lesson may be taken to be that propositional and doxastic justification are in a relation of intertwinement. (shrink)

I extend the Higher-Order View of Undermining Defeat (HOVUD) defended in Melis (2014) to account for the defeat of propositional justification. In doing so, I clarify the important notion of higher-order commitment, and I make some considerations concerning the defeat of externalist epistemic warrants.