Message Exchange Games in Strategic Contexts

When two people engage in a conversation, knowingly or unknowingly, they are playing a game. Players of such games have diverse objectives, or winning conditions: an applicant trying to convince her potential employer of her eligibility over that of a competitor, a prosecutor trying to convict a defendant, a politician trying to convince an electorate in a political debate, and so on. We argue that infinitary games offer a natural model for many structural characteristics of such conversations. We call such games message exchange games, and we compare them to existing game theoretic frameworks used in linguistics—for example, signaling games—and show that message exchange games are needed to handle non-cooperative conversation. In this paper, we concentrate on conversational games where players’ interests are opposed. We provide a taxonomy of conversations based on their winning conditions, and we investigate some essential features of winning conditions like consistency and what we call rhetorical cooperativity. We show that these features make our games decomposition sensitive, a property we define formally in the paper. We show that this property has far-reaching implications for the existence of winning strategies and their complexity. There is a class of winning conditions (decomposition invariant winning conditions) for which message exchange games are equivalent to Banach- Mazur games, which have been extensively studied and enjoy nice topological results. But decomposition sensitive goals are much more the norm and much more interesting linguistically and philosophically.     

Analogous selection processes in declarative and procedural working memory: N-2 list-repetition and task-repetition costs

Working memory (WM) holds and manipulates representations for ongoing cognition. Oberauer (Psychology of Learning and Motivation, 51, 45–100, 2009) distinguishes between two analogous WM sub-systems: a declarative WM which handles the objects of thought, and a procedural WM which handles the representations of (cognitive) actions. Here, we assessed whether analogous effects are observed when participants switch between memory sets (declarative representations) and when they switch between task sets (procedural representations). One mechanism assumed to facilitate switching in procedural WM is the inhibition of previously used, but currently irrelevant task sets, as indexed by n-2 task-repetition costs (Mayr & Keele, Journal of Experimental Psychology: General, 129(1), 4–26, 2000). In this study we tested for an analogous effect in declarative WM. We assessed the evidence for n-2 list-repetition costs across eight experiments in which participants switched between memory lists to perform speeded classifications, mental arithmetic, or a local recognition test. N-2 list-repetition costs were obtained consistently in conditions assumed to increase interference between memory lists, and when lists formed chunks in long-term memory. Further analyses across experiments revealed a substantial contribution of episodic memory to n-2 list-repetition costs, thereby questioning the interpretation of n-2 repetition costs as reflecting inhibition. We reanalyzed the data of eight task-switching experiments, and observed that episodic memory also contributes to n-2 task-repetition costs. Taken together, these results show analogous processing principles in declarative and procedural WM, and question the relevance of inhibitory processes for efficient switching between mental sets.     

Neuromodulation can reduce aggressive behavior elicited by violent video games

Research has shown that exposure to violent media increases aggression. However, the neural underpinnings of violent-media-related aggression are poorly understood. Additionally, few experiments have tested hypotheses concerning how to reduce violent-media-related aggression. In this experiment, we focused on a brain area involved in the regulation of aggressive impulses—the right ventrolateral prefrontal cortex (rVLPFC). We tested the hypothesis that brain polarization through anodal transcranial direct current stimulation (tDCS) over rVLPFC reduces aggression related to violent video games. Participants (N = 79) were randomly assigned to play a violent or a nonviolent video game while receiving anodal or sham stimulation. Afterward, participants aggressed against an ostensible partner using the Taylor aggression paradigm (Taylor Journal of Personality, 35, 297–310, 1967), which measures both unprovoked and provoked aggression. Among those who received sham stimulation, unprovoked aggression was significantly higher for violent-game players than for nonviolent-game players. Among those who received anodal stimulation, unprovoked aggression did not differ for violent- and nonviolent-game players. Thus, anodal stimulation reduced unprovoked aggression in violent-game players. No significant effects were found for provoked aggression, suggesting tit-for-tat responding. This experiment sheds light on one possible neural underpinning of violent-media-related aggression—the rVLPFC, a brain area involved in regulating negative feelings and aggressive impulses.     

Congruence Lattices of Semilattices with Operators

The duality between congruence lattices of semilattices, and algebraic subsets of an algebraic lattice, is extended to include semilattices with operators. For a set G of operators on a semilattice S, we have \({{\rm Con}(S,+,0,G) \cong^{d} {{\rm S}_{p}}(L,H)}\), where L is the ideal lattice of S, and H is a corresponding set of adjoint maps on L. This duality is used to find some representations of lattices as congruence lattices of semilattices with operators. It is also shown that these congruence lattices satisfy the Jónsson–Kiefer property.     

Reapproaching Ramsey: Conditionals and Iterated Belief Change in the Spirit of AGM

According to the Ramsey Test, conditionals reflect changes of beliefs: α?>?β is accepted in a belief state iff β is accepted in the minimal revision of it that is necessary to accommodate α. Since Gärdenfors’s seminal paper of 1986, a series of impossibility theorems (“triviality theorems”) has seemed to show that the Ramsey test is not a viable analysis of conditionals if it is combined with AGM-type belief revision models. I argue that it is possible to endorse that Ramsey test for conditionals while staying true to the spirit of AGM. A main focus lies on AGM’s condition of Preservation according to which the original belief set should be fully retained after a revision by information that is consistent with it. I use concrete representations of belief states and (iterated) revisions of belief states as semantic models for (nested) conditionals. Among the four most natural qualitative models for iterated belief change, two are identified that indeed allow us to combine the Ramsey test with Preservation in the language containing only flat conditionals of the form α?>?β. It is shown, however, that Preservation for this simple language enforces a violation of Preservation for nested conditionals of the form α?>?(β?>?γ). In such languages, no two belief sets are ordered by strict subset inclusion. I argue that it has been wrong right from the start to expect that Preservation holds in languages containing nested conditionals.     

The Mereological Foundation of Megethology

In Mathematics is megethology (Lewis (1993). Philosophia Mathematica, 1(1), 3–23) David K. Lewis proposes a structuralist reconstruction of classical set theory based on mereology. In order to formulate suitable hypotheses about the size of the universe of individuals without the help of set-theoretical notions, he uses the device of Boolos’ plural quantification for treating second order logic without commitment to set-theoretical entities. In this paper we show how, assuming the existence of a pairing function on atoms, as the unique assumption non expressed in a mereological language, a mereological foundation of set theory is achievable within first order logic. Furthermore, we show how a mereological codification of ordered pairs is achievable with a very restricted use of the notion of plurality without plural quantification.     

The Modal Logic of Gödel Sentences

The modal logic of Gödel sentences, termed as GS, is introduced to analyze the logical properties of ‘true but unprovable’ sentences in formal arithmetic. The logic GS is, in a sense, dual to Grzegorczyk’s Logic, where modality can be interpreted as ‘true and provable’. As we show, GS and Grzegorczyk’s Logic are, in fact, mutually embeddable. We prove Kripke completeness and arithmetical completeness for GS. GS is also an extended system of the logic of ‘Essence and Accident’ proposed by Marcos (Bull Sect Log 34(1):43–56, 2005). We also clarify the relationships between GS and the provability logic GL and between GS and Intuitionistic Propositional Logic.     

Reasoning defeasibly about probabilities

In concrete applications of probability, statistical investigation gives us knowledge of some probabilities, but we generally want to know many others that are not directly revealed by our data. For instance, we may know prob(P/Q) (the probability of P given Q) and prob(P/R), but what we really want is prob(P/Q&;R), and we may not have the data required to assess that directly. The probability calculus is of no help here. Given prob(P/Q) and prob(P/R), it is consistent with the probability calculus for prob(P/Q&;R) to have any value between 0 and 1. Is there any way to make a reasonable estimate of the value of prob(P/Q&;R)? A related problem occurs when probability practitioners adopt undefended assumptions of statistical independence simply on the basis of not seeing any connection between two propositions. This is common practice, but its justification has eluded probability theorists, and researchers are typically apologetic about making such assumptions. Is there any way to defend the practice? This paper shows that on a certain conception of probability—nomic probability—there are principles of “probable probabilities” that license inferences of the above sort. These are principles telling us that although certain inferences from probabilities to probabilities are not deductively valid, nevertheless the second-order probability of their yielding correct results is 1. This makes it defeasibly reasonable to make the inferences. Thus I argue that it is defeasibly reasonable to assume statistical independence when we have no information to the contrary. And I show that there is a function Y(r, s, a) such that if prob(P/Q) = r, prob(P/R) = s, and prob(P/U) = a (where U is our background knowledge) then it is defeasibly reasonable to expect that prob(P/Q&;R) = Y(r, s, a). Numerous other defeasible inferences are licensed by similar principles of probable probabilities. This has the potential to greatly enhance the usefulness of probabilities in practical application.     

A class of k-modes algorithms for extracting knowledge structures from data

One of the most crucial issues in knowledge space theory is the construction of the so-called knowledge structures. In the present paper, a new data-driven procedure for large data sets is described, which overcomes some of the drawbacks of the already existing methods. The procedure, called k-states, is an incremental extension of the k-modes algorithm, which generates a sequence of locally optimal knowledge structures of increasing size, among which a “best” model is selected. The performance of k-states is compared to other two procedures in both a simulation study and an empirical application. In the former, k-states displays a better accuracy in reconstructing knowledge structures; in the latter, the structure extracted by k-states obtained a better fit.     

Determination of the number of independent parameters of a score matrix from the examination of rank orders

Two ordinal consequences are drawn from the linear multiple-factor analysis model. First, the numberR(s, d) of distinct ways in whichs subjects can be ranked by linear functions ofd factors is limited by the recursive expressionR(s, d)=R(s?1,d)+(s?1)R(s?1,d?1). Second, every setS ofd+2 subjects can be separated into two subsetsS* andS ? S* such that no linear function ofd variables can rank allS* over allS ? S*, and vice versa. When these results are applied to the hypothetical data of Thurstone's “box problem,” three independent parameters are found. Relations to Thurstone's suggestion for a non-correlational factor analysis are discussed.     

Antisocial Process Screening Device Subscales Predict Recidivism in an Australian Juvenile Offender Sample

The present study is the first to examine the psychometric properties of the self-report Antisocial Process Screening Device (APSD-SR), and the predictive utility of its subscales for reoffending, among Australian juvenile offenders (N?= 308, M age = 17.00, SD?=?1.49). Exploratory factor analysis supported a modified three-factor structure in which four items loaded differently to prior studies. Total APSD-SR and modified subscale scores were positively associated with criminal history and mental health problems (e.g., internalizing and externalizing problems, alcohol and substance abuse/dependence). Survival analyses indicated that youth scoring high on the APSD-SR total score were faster to reoffend nonviolently (Hazard Ratio [HR]?= 1.31, p?=?.0003) and violently (HR?=?1.42, p?=?.0003) than those scoring low. Whereas the modified grandiose-manipulative subscale predicted faster time to nonviolent recidivism (HR?=?1.18, p?=?.026) as a single predictor, when all subscales were simultaneously entered into the model only callous-unemotional (CU) traits and impulsivity predicted nonviolent recidivism (HR?=?1.19, p?=?.026 and 1.22, p?=?.015, respectively), and only impulsivity predicted violent recidivism (HR?=?1.26, p?=?.014). Findings inform current understanding of the relative contribution of adolescent psychopathy dimensions to designating a particularly high-risk group of Australian youth in custody.     

Analytic Tableaux for all of <Emphasis Type="Italic">SIXTEEN</Emphasis><Subscript>3</Subscript>

In this paper we give an analytic tableau calculus P L _{1 6} for a functionally complete extension of Shramko and Wansing’s logic. The calculus is based on signed formulas and a single set of tableau rules is involved in axiomatising each of the four entailment relations ? _t , ? _f , ? _i , and ? under consideration—the differences only residing in initial assignments of signs to formulas. Proving that two sets of formulas are in one of the first three entailment relations will in general require developing four tableaux, while proving that they are in the ? relation may require six.     

Consequence Mining

The standard semantic definition of consequence with respect to a selected set X of symbols, in terms of truth preservation under replacement (Bolzano) or reinterpretation (Tarski) of symbols outside X, yields a function mapping X to a consequence relation \(\Rightarrow_X\). We investigate a function going in the other direction, thus extracting the constants of a given consequence relation, and we show that this function (a) retrieves the usual logical constants from the usual logical consequence relations, and (b) is an inverse to—more precisely, forms a Galois connection with—the Bolzano–Tarski function.     

Subjunctive Conditional Probability

There seem to be two ways of supposing a proposition: supposing “indicatively” that Shakespeare didn’t write Hamlet, it is likely that someone else did; supposing “subjunctively” that Shakespeare hadn’t written Hamlet, it is likely that nobody would have written the play. Let P(B//A) be the probability of B on the subjunctive supposition that A. Is P(B//A) equal to the probability of the corresponding counterfactual, A □→B? I review recent triviality arguments against this hypothesis and argue that they do not succeed. On the other hand, I argue that even if we can equate P(B//A) with P(A □→B), we still need an account of how subjunctive conditional probabilities are related to unconditional probabilities. The triviality arguments reveal that the connection is not as straightforward as one might have hoped.     

Gesture as representational action: A paper about function

A great deal of attention has recently been paid to gesture and its effects on thinking and learning. It is well established that the hand movements that accompany speech are an integral part of communication, ubiquitous across cultures, and a unique feature of human behavior. In an attempt to understand this intriguing phenomenon, researchers have focused on pinpointing the mechanisms that underlie gesture production. One proposal––that gesture arises from simulated action (Hostetter & Alibali Psychonomic Bulletin & Review, 15, 495–514, 2008)––has opened up discussions about action, gesture, and the relation between the two. However, there is another side to understanding a phenomenon and that is to understand its function. A phenomenon’s function is its purpose rather than its precipitating cause––the why rather than the how. This paper sets forth a theoretical framework for exploring why gesture serves the functions that it does, and reviews where the current literature fits, and fails to fit, this proposal. Our framework proposes that whether or not gesture is simulated action in terms of its mechanism––it is clearly not reducible to action in terms of its function. Most notably, because gestures are abstracted representations and are not actions tied to particular events and objects, they can play a powerful role in thinking and learning beyond the particular, specifically, in supporting generalization and transfer of knowledge.     

Wittgenstein as a Philosopher of Technology: Tool Use,Forms of Life,Technique, and a Transcendental Argument

The work of Ludwig Wittgenstein is seldom used by philosophers of technology, let alone in a systematic way, and in general there has been little discussion about the role of language in relation to technology. Conversely, Wittgenstein scholars have paid little attention to technology in the work of Wittgenstein. In this paper we read the Philosophical Investigations and On Certainty in order to explore the relation between language use and technology use, and take some significant steps towards constructing a framework for a Wittgensteinian philosophy of technology. This framework takes on board, and is in line with, insights from postphenomenological and hermeneutic approaches, but moves beyond those approaches by benefiting from Wittgenstein’s insights into the use of tools, technique, and performance, and by offering a transcendental interpretation of games, forms of life, and grammar. Focusing on Wittgenstein’s philosophy of language in the Investigations, we first discuss the relation between language use and technology use, understood as tool use, by drawing on his analogy between language and tools. This suggests a more general theory of technology use, understood as performance. Then we turn to his epistemology and argue that Wittgenstein’s understanding of language use can be embedded within a more general theory about technology use understood as tool use and technique, since language-in-use is always already a skilled and embodied technological practice. Finally, we propose a transcendental interpretation of games, forms of life, and grammar, which also gives us a transcendental way of looking at technique, technological practice, and performance. With this analysis and interpretation, further supported by comments on robotics and music, we contribute to using and integrating Wittgenstein in a more systematic way within philosophy of technology and engage with perennial questions from the philosophical tradition.     

Fer-ho Anaphora in Catalan: Semantic and Discourse Properties

This paper considers the anaphoric status of the pro-form fer-ho (do it) in Catalan [This paper contains some ideas included in Busquets (2005)]. I discuss some anaphoric properties of fer-ho as deep anaphora. I also compare these properties to those of other types of anaphora, like VPE and pseudogapping (pg). I show that its interpretation is strongly constrained by information and discourse structure.     

Decisional Procrastination: Assessing Characterological and Contextual Variables around Indecision

University students (n = 75; M age = 21.4 years old) and community adults (n = 55: M age = 36.6 years old) completed self-reported measures of decisional procrastination (indecision), character (life satisfaction, meaningful life, and need for cognition), context (place attachment, sense of community, and psychological home) and “cross-over” factors relating character and context (self-identity with possessions, people/thing orientation, and clutter), to provide an ecological understanding of persons who claim indecision. Controlling for social desirability tendencies, indecision was negatively related to all character but none of the context variables. Indecision also was related to both person and thing orientation and clutter. Multiple regression analysis indicated that only need for cognition significantly predicted (negatively) indecision among character, context, and cross-over variable sets. Subjective well-being also predicted indecision with low need for cognition among cross-over variables. Taken together, decisional procrastinators reported too much clutter (stuff), interfering with a positive quality of life and related to character over context and cross-over, ecological variables.     

The Hidden Set-Theoretical Paradox of the <Emphasis Type="Italic">Tractatus</Emphasis>

We are familiar with various set-theoretical paradoxes such as Cantor's paradox, Burali-Forti's paradox, Russell's paradox, Russell-Myhill paradox and Kaplan's paradox. In fact, there is another new possible set-theoretical paradox hiding itself in Wittgenstein’s Tractatus (Wittgenstein 1989). From the Tractatus’s Picture theory of language (hereafter LP) we can strictly infer the two contradictory propositions simultaneously: (a) the world and the language are equinumerous; (b) the world and the language are not equinumerous. I call this antinomy the world-language paradox. Based on a rigorous analysis of the Tractatus, with the help of the technical resources of Cantor’s naive set theory (Cantor in Mathematische Annalen, 46, 481–512, 1895, Mathematische Annalen, 49, 207–246, 1897) and Zermelo-Fraenkel set theory with the axiom of choice (hereafter ZFC) (Jech 2006: 3–15; Kunen 1992: xv–xvi; Bagaria 2008: 619–622), I outline the world-language paradox and assess the unique possible solution plan, i.e., the mathematical plan utilizing ‘infinity’. I conclude that Wittgenstein cannot solve the hidden set-theoretical paradox of the Tractatus successfully unless he gives up his finitism.     

Contested Technologies and Design for Values: The Case of Shale Gas

The introduction of new energy technologies may lead to public resistance and contestation. It is often argued that this phenomenon is caused by an inadequate inclusion of relevant public values in the design of technology. In this paper we examine the applicability of the value sensitive design (VSD) approach. While VSD was primarily introduced for incorporating values in technological design, our focus in this paper is expanded towards the design of the institutions surrounding these technologies, as well as the design of stakeholder participation. One important methodological challenge of VSD is to identify the relevant values related to new technological developments. In this paper, we argue that the public debate can form a rich source from which to retrieve the values at stake. To demonstrate this, we have examined the arguments used in the public debate regarding the exploration and exploitation of shale gas in the Netherlands. We identified two important sets of the underlying values, namely substantive and procedural values. This paper concludes with two key findings. Firstly, contrary to what is often suggested in the literature, both proponents and opponents seem to endorse the same values. Secondly, contestation seems to arise in the precise operationalization of these values among the different stakeholders. In other words, contestation in the Dutch shale gas debate does not arise from inter-value conflict but rather from intra-value conflicts. This multi-interpretability should be incorporated in VSD processes.