•  10
    Dynamic epistemic logics for abstract argumentation
    with Antonio Yuste-Ginel
    Synthese 199 (3-4): 8641-8700. 2021.
    This paper introduces a multi-agent dynamic epistemic logic for abstract argumentation. Its main motivation is to build a general framework for modelling the dynamics of a debate, which entails reasoning about goals, beliefs, as well as policies of communication and information update by the participants. After locating our proposal and introducing the relevant tools from abstract argumentation, we proceed to build a three-tiered logical approach. At the first level, we use the language of propo…Read more
  •  20
    Bivalence and future contingency
    with Gabriel Sandu and Francois Rivenc
    In Vincent Hendricks & Sven Ove Hansson (eds.), Handbook of Formal Philosophy, Springer. forthcoming.
    This work presents an overview of four different approaches to the problem of future contingency and determinism in temporal logics. All of them are bivalent, viz. they share the assumption that propositions concerning future contingent facts have a determinate truth-value. We introduce Ockhamism, Peirceanism, Actualism and T x W semantics, the four most relevant bivalent alternatives in this area, and compare them from the point of view of their expressiveness and their underlying metaphysics o…Read more
  •  17
    This paper studies the relation between persuasive argumentation and the speaker’s epistemic attitude. Dung-style abstract argumentation and dynamic epistemic logic provide the necessary tools to characterize the notion of persuasion. Within abstract argumentation, persuasive argumentation has been previously studied from a game-theoretic perspective. These approaches are blind to the fact that, in real-life situations, the epistemic attitude of the speaker determines which set of arguments will…Read more
  •  6
    Discussion among individuals about a given issue often induces polarization and bipolarization effects, i.e. individuals radicalize their initial opinion towards either the same or opposite directions. Experimental psychologists have put forward Persuasive Arguments Theory as a clue for explaining polarization. PAT claims that adding novel and persuasive arguments pro or contra the debated issue is the major cause for polarization. Recent developments in abstract argumentation provide the tools …Read more
  •  6
    Understanding Group Polarization with Bipolar Argumentation Frameworks
    Frontiers in Artificial Intelligence and Applications 287. 2016.
    Group polarization occurs when an initial attitude or belief of individuals becomes more radical after group discussion. Polarization often leads subgroups towards opposite directions. Since the 1960s this effect has been observed and repeatedly confirmed in lab experiments by social psychologists. Persuasive Arguments Theory emerged as the most convincing explanation for this phenomenon. This paper is a first attempt to frame the PAT explanation more formally by means of Bipolar Argumentation F…Read more
  •  2
    The Peter Principle states that employees tend to be promoted until they reach their level of incompetence. In a sophisticated simulation study, Pluchino et al confirmed a version of the principle. However, they also noted that their model has the counterintuitive consequence that “the best ways for improving the efficiency of a given organization are either to promote each time an agent at random or to promote randomly the best and the worst members”. We argue that what promotion rule is used c…Read more
  •  13
    Probabilistic Semantics for a Discussive Temporal Logic
    with Roberto Ciuni
    The Logica Yearbook. forthcoming.
    The paper introduces a probabilistic semantics for the paraconsistent temporal logic Ab presented by the authors in a previous work on future contingents. Probabilistic concepts help framing two possible interpretations of the logic in question - a `subjective' and an `objective' one - and explaining the rationale behind both of them. We also sketch a proof-method for Ab and address some considerations regarding the conceptual appeal of our proposal and its possible future developments.
  •  9
    Explicating Ignorance and Doubt : A Possible Worlds Approach
    In Rik Peels & Martijn Blaauw (eds.), The Epistemic Dimensions of Ignorance, Cambridge University Press. pp. 81-95. 2016.
  •  2
    Ceteris paribus modalities and the future contingents problem
    In Lena Kurzen & Fernando Velasquez Quesada (eds.), Logics for Dynamics of Information and Preferences., . pp. 304-325. 2009.
    This paper presents two systems of temporal logic, \Lambda_{CPT} and \Lambda_{[email protected]}, with ceteris paribus modalities. The principal aim is to show how this approach can be useful to give an ockhamist solution to the future contingents problem along the same lines of A. Prior. The interest of this work lies also in the fact that \Lambda_{[email protected]} represents an alternative modal account of supervaluationist and post-semantics approaches to temporal reasoning.
  •  28
    The problem of future contingents is one of the most ancient and debated puzzles in Western philosophy, and Supervaluationism is, today, one of the most prominent solutions to the problem. Recently, John MacFarlane has carried a well-known criticism to Supervaluationism and put forward a new solution of the problem of future contingents, which is known as Double Time Reference Theory. Here, we compare DTRT with Supervaluationist semantics, and we show that the success of MacFarlane's criticism c…Read more
  •  2
    Discussion among individuals about a given issue often induces polarization and bipolarization effects, i.e. individuals radicalize their initial opinion towards either the same or opposite directions. Experimental psychologists have put forward Persuasive Arguments Theory as a clue for explaining polarization. PAT claims that adding novel and persuasive arguments pro or contra the debated issue is the major cause for polarization. Recent developments in abstract argumentation provide the tools …Read more
  •  8
    The dynamics of group polarization
    In Alexandru Baltag, Jeremy Seligman & Tomoyuki Yamada (eds.), Logic, Rationality, and Interaction. LORI 2017. Lecture Notes in Computer Science, vol 10455, Springer. pp. 195-208. 2017.
    Exchange of arguments in a discussion often makes individuals more radical about their initial opinion. This phenomenon is known as Group-induced Attitude Polarization. A byproduct of it are bipolarization effects, where the distance between the attitudes of two groups of individuals increases after the discussion. This paper is a first attempt to analyse the building blocks of information exchange and information update that induce polarization. I use Argumentation Frameworks as a tool for enco…Read more
  •  5
    Claude Gratton, Infinite Regress Arguments
    Cogency - Journal of Reasoning and Argumentation 4 (1): 213-215. 2012.
  •  53
    Mereology and time travel
    Philosophical Studies 177 (8): 2245-2260. 2020.
    Core principles of mereology have been questioned by appealing to time travel scenarios. This paper questions the methodology of employing time travel scenarios to argue against mereology. We show some time travel scenarios are structurally equivalent to more standard ones not involving time travel; and that the three main theories about persistence through time can each solve both the time travel scenario as well as the structurally similar classical scenario. Time travel scenarios that are not…Read more
  •  37
    The Fitch-Church Paradox and First Order Modal Logic
    Erkenntnis 81 (1): 87-104. 2016.
    Reformulation strategies for solving Fitch’s paradox of knowability date back to Edgington. Their core assumption is that the formula \, from which the paradox originates, does not correctly express the intended meaning of the verification thesis, which should concern possible knowledge of actual truths, and therefore the contradiction does not represent a logical refutation of verificationism. Supporters of these solutions claim that can be reformulated in a way that blocks the derivation of th…Read more
  •  44
    We provide a brief introduction to this special issue on social dynamics and collective rationality, and summarize the gist of the papers collected therein
  •  21
    Reflecting on Social Influence in Networks
    with Zoé Christoff and Jens Ulrik Hansen
    Journal of Logic, Language and Information 25 (3-4): 299-333. 2014.
    In many social contexts, social influence seems to be inescapable: the behavior of others influences us to modify ours, and vice-versa. However, social psychology is full of examples of phenomena where individuals experience a discrepancy between their public behavior and their private opinion. This raises two central questions. First, how does an individual reason about the behavior of others and their private opinions in situations of social influence? And second, what are the laws of the resu…Read more
  •  54
    Natural Numbers and Infinitesimals: A Discussion between Benno Kerry and Georg Cantor
    History and Philosophy of Logic 29 (4): 343-359. 2008.
    During the first months of 1887, while completing the drafts of his Mitteilungen zur Lehre vom Transfiniten, Georg Cantor maintained a continuous correspondence with Benno Kerry. Their exchange essentially concerned two main topics in the philosophy of mathematics, namely, (a) the concept of natural number and (b) the infinitesimals. Cantor's and Kerry's positions turned out to be irreconcilable, mostly because of Kerry's irremediably psychologistic outlook, according to Cantor at least. In this…Read more
  •  48
    Intuitionistic Epistemic Logic, Kripke Models and Fitch’s Paradox
    Journal of Philosophical Logic 41 (5): 877-900. 2012.
    The present work is motivated by two questions. (1) What should an intuitionistic epistemic logic look like? (2) How should one interpret the knowledge operator in a Kripke-model for it? In what follows we outline an answer to (2) and give a model-theoretic definition of the operator K. This will shed some light also on (1), since it turns out that K, defined as we do, fulfills the properties of a necessity operator for a normal modal logic. The interest of our construction also lies in a better…Read more
  •  75
    A DDL Approach to Pluralistic Ignorance and Collective Belief
    with Erik J. Olsson
    Journal of Philosophical Logic 43 (2-3): 499-515. 2014.
    A group is in a state of pluralistic ignorance (PI) if, roughly speaking, every member of the group thinks that his or her belief or desire is different from the beliefs or desires of the other members of the group. PI has been invoked to explain many otherwise puzzling phenomena in social psychology. The main purpose of this article is to shed light on the nature of PI states – their structure, internal consistency and opacity – using the formal apparatus of Dynamic Doxastic Logic, and also to …Read more
  •  313
    Fitch’s paradox and ceteris paribus modalities
    Synthese 173 (1): 75-87. 2010.
    The paper attempts to give a solution to the Fitch's paradox though the strategy of the reformulation of the paradox in temporal logic, and a notion of knowledge which is a kind of ceteris paribus modality. An analogous solution has been offered in a different context to solve the problem of metaphysical determinism.
  •  62
    The abundance of the future. A paraconsistent approach to future contingents
    with Roberto Ciuni
    Logic and Logical Philosophy 22 (1): 21-43. 2013.
    Supervaluationism holds that the future is undetermined, and as a consequence of this, statements about the future may be neither true nor false. In the present paper, we explore the novel and quite different view that the future is abundant: statements about the future do not lack truth-value, but may instead be glutty, that is both true and false. We will show that (1) the logic resulting from this “abundance of the future” is a non-adjunctive paraconsistent formalism based on subvaluations, w…Read more