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 Frameworks. In particular, I show (...) that polarization may emerge in a BAF by simple and rational belief updates by participants. (shrink)

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 encoding the information of agents (...) in a debate relative to a given issue a. I then adapt a specific measure of the degree of acceptability of an opinion. Changes in the degree of acceptability of a, prior and posterior to information exchange, serve here as an indicator of polarization. I finally show that the way agents transmit and update information has a decisive impact on polarization and bipolarization. (shrink)

This article argues that philosophers and laypeople commonly conceptualize moral truths or justified moral beliefs as discoverable through intuition, argument, or some other purely cognitive or affective process. It then contends that three empirically well-supported theories all predict that this ‘Discovery Model’ of morality plays a substantial role in causing social polarization. The same three theories are then used to argue that an alternative ‘Negotiation Model’ of morality—according to which moral truths are not discovered but instead created by actively (...) negotiating compromises—promises to reduce polarization by fostering a progressive willingness to ‘work across the aisle’ to settle moral issues cooperatively. This article then examines potential methods for normatively evaluating polarization, arguing there are prima facie reasons to favor the Negotiation Model over the Discovery Model based on their hypothesized effects on polarization. Finally, I outline avenues for further empirical and philosophical research. (shrink)

Predictable polarization is everywhere: we can often predict how people’s opinions, including our own, will shift over time. Extant theories either neglect the fact that we can predict our own polarization, or explain it through irrational mechanisms. They needn’t. Empirical studies suggest that polarization is predictable when evidence is ambiguous, that is, when the rational response is not obvious. I show how Bayesians should model such ambiguity and then prove that—assuming rational updates are those which obey the (...) value of evidence—ambiguity is necessary and sufficient for the rationality of predictable polarization. The main theoretical result is that there can be a series of such updates, each of which is individually expected to make you more accurate, but which together will predictably polarize you. Polarization results from asymmetric increases in accuracy. This mechanism is not only theoretically possible, but empirically plausible. I argue that cognitive search—searching a cognitively accessible space for a particular item—often yields asymmetrically ambiguous evidence, I present an experiment supporting its polarizing effects, and I use simulations to show how it can explain two of the core causes of polarization: confirmation bias and the group polarization effect. (shrink)

We are increasingly exposed to polarized media sources, with clear evidence that individuals choose those sources closest to their existing views. We also have a tradition of open face-to-face group discussion in town meetings, for example. There are a range of current proposals to revive the role of group meetings in democratic decision-making. Here, we build a simulation that instantiates aspects of reinforcement theory in a model of competing social influences. What can we expect in the interaction of (...) polarized media with group interaction along the lines of town meetings? Some surprises are evident from a computational model that includes both. Deliberative group discussion can be expected to produce opinion convergence. That convergence may not, however, be a cure for extreme views polarized at opposite ends of the opinion spectrum. In a large class of cases, we show that adding the influence of group meetings in an environment of self-selected media produces not a moderate central consensus but opinion convergence at one of the extremes defined by polarized media. (shrink)

The study’s two aims are: to investigate whether groups, as compared to individuals, show a different degree of Endowment Effect during the negotiating of intangible assets, such as leisure time and to gain some insight into the underlying mechanism behind groups’ decision-making processes. A total of 138 graduate students were randomly assigned to 35 groups of 3 members each; and 33 were randomly labeled as “individuals.” The study simulated two scenarios in which the students, both individuals and groups, had (...) to decide what their demands from the university authorities were—once as “sellers” and another time as “buyers” in regard to their own leisure time. The findings indicate the presence of an Endowment Effect in both individuals and groups. However, groups significantly amplified the Endowment Effect in comparison to individuals. The mechanism which best explains why groups tend to amplify negotiating decisions was found to be the “Majority Rule,” but the “leader” also influences such amplification. (shrink)

The powerful role that teachers can play in our development is the focus Binyamin, Jayusi, and Tamir’s chapter in this volume. They argue that teachers, in particular teachers that don’t share the same background as their students, can help counter the increasing polarization that characterizes our current era. In these critical notes I raise three challenges to their proposal. First, by exploring the mechanisms of polarization I demonstrate that polarization is not a problem unique to thick diversity (...) or thick multiculturalism. Second, the central premise of the authors’ proposal rests on the ability of greater contact to reduce prejudice. The contact hypothesis, however, has numerous backlash effects and unintended consequences that can increase prejudice rather than reduce prejudice. These backlash effects and unintended consequences raise serious doubts for the success of placing minority teachers in majority classrooms to reduce prejudice. Third, I raise concerns about how the proposal tokenizes minority teachers, the use of instrumental rationales for diversity, and the politics of deference and being-in-the-room privilege that also go unaddressed in their proposal. (shrink)

Most donated organs in the United States come from brain dead donors, while a small percentage come from patients who die in “controlled,” or expected, circumstances, typically after the family or surrogate makes a decision to withdraw life support. The number of organs available for transplant could be substantially if donations were permitted in “uncontrolled” circumstances–that is, from people who die unexpectedly, often outside the hospital. According to projections from the Institute of Medicine, establishing programs permitting “uncontrolled donation after circulatory (...) determination of death,” or uDCDD, throughout the United States has the potential to provide 22,000 more donation opportunities annually. In contrast, U.S. controlled donation after circulatory determination of death, or cDCDD, cases have increased progressively over the past decade from 87 to 848 donors, but currently account for only 10.6 percent of all deceased donors. Following the IOM recommendations, several projects exploring the feasibility of uDCDD were funded by the federal government, including a grant from the Health Resources and Services Administration that supported a pilot project in New York City in which the authors of this article participated.A key feature of our protocol, and indeed of many uDCDD protocols, is the initiation of preservation methods such as chest compressions and extracorporeal membrane oxygenation shortly after death in order to perfuse and preserve the donor's organs. Critics of uDCDD argue that the means of determining death deviates from generally ascribed principles. They assert that reinstituting circulation in order to preserve organs has the effect of “undoing” the prior determination of death. The result is that cDCDD is widely accepted and practiced routinely even though it only marginally increases the number of organs available for transplantation, and uDCDD is widely considered unacceptable despite being ethically embraced and proven to significantly increase organ donation opportunities in other countries. This article explores the evolution of this counterintuitive state of affairs and calls for a policy that, in line with the IOM report, allows for both cDCDD and uDCDD protocols. (shrink)

According to some, the current political fracture is best described as political polarization – where extremism and political separation infest an entire whole population. Political polarization accounts often point to the psychological phenomenon of belief polarization – where being in a like-minded groups tends to boost confidence. The political polarization story is an essentially symmetrical one, where both sides are subject to the same basic dividing forces and cognitive biases, and are approximately as blame-worthy. On a (...) very different account, what's going on is best described propaganda – where a discrete set of bad actors have manipulated some part of the media environ-ment. The propaganda story is usually told as a highly asymmetrical story, where only some media consumers are under the spell of the propagandists. Which is right? I consider two analyses of the 2016 American election: Robert Talisse's polarization-style account in Overdoing Democracy, and Benkler et. al.'s propaganda-style account in Network Propaganda. I suggest that the propaganda account has better empirical support. I also offer a diagnosis of the appeal of the polarization story. Those who accept a polarization account are often political centrists, who accuse those at the political extremes of motivated reasoning – of believing what they find comfortable. Such centrists also tend to treat political extremism as the product of the irrational belief polarization, arising from living in like-minded groups. But, I argue, these arguments are too quick. First, we can’t dismiss a group as irrational merely be-cause they are likeminded. The existence of like-minded group can be explained in terms of irrational belief polarization, but it can also be explained by rational convergence on the truth. Second, belief polarization is not always irrational, such as when its emotional effects are used to repair impaired self-confidence. Third, political centrists are also subject to similar debunking argument. When we accept a polarization account, we get to feel the comfort of being “above it all”. Political centrists are just as plausibly subject to the irrational effects of living in like-minded groups. Belief polarization isn’t just for extremists. (shrink)

Belief polarization is said to occur when two people respond to the same evidence by updating their beliefs in opposite directions. This response is considered to be “irrational” because it involves contrary updating, a form of belief updating that appears to violate normatively optimal responding, as for example dictated by Bayes' theorem. In light of much evidence that people are capable of normatively optimal behavior, belief polarization presents a puzzling exception. We show that Bayesian networks, or Bayes nets, (...) can simulate rational belief updating. When fit to experimental data, Bayes nets can help identify the factors that contribute to polarization. We present a study into belief updating concerning the reality of climate change in response to information about the scientific consensus on anthropogenic global warming. The study used representative samples of Australian and U.S. participants. Among Australians, consensus information partially neutralized the influence of worldview, with free-market supporters showing a greater increase in acceptance of human-caused global warming relative to free-market opponents. In contrast, while consensus information overall had a positive effect on perceived consensus among U.S. participants, there was a reduction in perceived consensus and acceptance of human-caused global warming for strong supporters of unregulated free markets. Fitting a Bayes net model to the data indicated that under a Bayesian framework, free-market support is a significant driver of beliefs about climate change and trust in climate scientists. Further, active distrust of climate scientists among a small number of U.S. conservatives drives contrary updating in response to consensus information among this particular group. (shrink)

This article aims to describe the last 10 years of the collaborative scientific endeavors on polarization in particular and collective problem-solving in general by our multidisciplinary research team. We describe the team’s disciplinary composition—social psychology, political science, social philosophy/epistemology, and complex systems science— highlighting the shared and unique skill sets of our group members and how each discipline contributes to studying polarization and collective problem-solving. With an eye to the literature on team dynamics, we describe team logistics (...) and processes that we believe make our multidisciplinary team persistent and productive. We emphasize challenges and difficulties caused by disciplinary differences in terms of terminology, units/levels of analysis, methodology, and theoretical assumptions. We then explain how work disambiguating the concepts of polarization and developing an integrative theoretical and methodological framework with complex systems perspectives has helped us overcome these challenges. We summarize the major findings that our research has produced over the past decade, and describe our current research and future directions. Last, we discuss lessons we have learned, including difficulties in a “three models” project and how we addressed them, with suggestions for effective multidisciplinary team research. (shrink)

Recent research on thick terms like “rude” and “friendly” has revealed a polarity effect, according to which the evaluative content of positive thick terms like “friendly” and “courageous” can be more easily canceled than the evaluative content of negative terms like “rude” and “selfish”. In this paper, we study the polarity effect in greater detail. We first demonstrate that the polarity effect is insensitive to manipulations of embeddings (Study 1). Second, we show that the effect occurs (...) not only for thick terms but also for thin terms such as “good” or “bad” (Study 2). We conclude that the polarity effect indicates a pervasive asymmetry between positive and negative evaluative terms. (shrink)

In this chapter, we turn our attention to the effects of the attention economy on our ability to act autonomously as a group. We begin by clarifying which sorts of groups we are concerned with, which are structured groups (groups sufficiently organized that it makes sense to attribute agency to the group itself). Drawing on recent work by Purves and Davis (2022), we describe the essential roles of trust (i.e., depending on groups to fulfill their commitments) and trustworthiness (...) (i.e., the property of a group that makes trusting them fitting) in autonomous group action, with particular emphasis on democratic institutions (which we view as group agents) and democratic legitimacy (which depends on trust and trustworthiness). We then explain how engagement maximization promotes polarization, which is detrimental to trust and trustworthiness and, in turn, democratic legitimacy and democratic institutions. We close by considering what groups might do to protect themselves from the threat posed to them by the attention economy. (shrink)

Group polarization—roughly, the tendency of groups to incline towards more extreme positions than initially held by their individual members— has been rigorously studied by social psychol- ogists, though in a way that has overlooked important philosophical questions about this phenomenon which remain unexplored. Two such salient questions are metaphysical and epistemological, respectively. From a metaphysical point of view, can group polarization, understood as an epistemic feature of a group, be reduced to epistemic features of its (...) individual members? Relatedly, from an epistemological point of view, is group polarization best understood as a kind of cognitive bias or rather in terms of intellectual vice? This book taxonomizes this possibility space by comparing four models which combine potential answers to the metaphysical and epistemological questions. The models we consider are: group polarization as a collective bias, a summation of individual epistemic vices; a summation of individual biases; and a collective epistemic vice. We defend a collective vice model of group polarization over the competing alternatives. (shrink)

How and Why Groups Polarize Polarization and Democracy Deliberative Trouble Notes.

Quantum mechanical and molecular dynamics methods were used to analyze the structure and stability of neutral and zwitterionic configurations of the extracted active site sequence from a Burkholderia cepacia lipase, histidyl-seryl-glutamin (His86-Ser87-Gln88) and its mutated form, histidyl-cysteyl-glutamin (His86-Cys87-Gln88) in vacuum and different solvents. The effects of solvent dielectric constant, explicit and implicit water molecules and side chain mutation on the structure and stability of this sequence in both neutral and zwitterionic forms are represented. The quantum mechanics computations represent that the (...) relative stability of zwitterionic and neutral configurations depends on the solvent structure and its dielectric constant. Therefore, in vacuum and the considered non-polar solvents, the neutral form of the interested sequences is more stable than the zwitterionic form, while their zwitterionic form is more stable than the neutral form in the aqueous solution and the investigated polar solvents in most cases. However, on the potential energy surfaces calculated, there is a barrier to proton transfer from the positively charged ammonium group to the negatively charged carboxylat group or from the ammonium group to the adjacent carbonyl oxygen and or from side chain oxygen and sulfur to negatively charged carboxylat group. Molecular dynamics simulations (MD) were also performed by using periodic boundary conditions for the zwitterionic configuration of the hydrated molecules in a box of water molecules. The obtained results demonstrated that the presence of explicit water molecules provides the more compact structures of the studied molecules. These simulations also indicated that side chain mutation and replacement of sulfur with oxygen leads to reduction of molecular flexibility and packing. (shrink)

Polarity Items are linguistic expressions known for being a ‘lexically controlled’ phenomenon. In this paper we show how their behavior can be implemented in a deductive system. Further- more, we point out some possible directions to recast the deductive solution into a Tree Ad- joining Grammar system. In particular, we suggest to compare the proof system developed for Multimodal Categorial Grammar (Moot & Puite, 1999) with the Partial Proof Trees proposed in (Joshi & Kulick, 1997).

There have been many discussions recently from philosophers, cognitive scientists, and psychologists about group polarization, with online and social media environments in particular receiving a lot of attention, both because of people's increasing reliance on such environments for receiving and exchanging information and because such environments often allow individuals to selectively interact with those who are like-minded. My goal here is to argue that the group epistemologist can facilitate understanding the kinds of factors that drive group (...) polarization in a way that has been overlooked by the existing research. Specifically, I argue that polarization can occur in part because of the ways that members of a group treat the group itself (as opposed to an individual member within that group) as a source of information, and in doing so makes their own position, as well as that of the group, more extreme. I refer to this as a structural factor in driving polarization, and argue that such factors can contribute to explanations of polarization that occurs specifically in an important subset of groups, namely online and social media groups in which little is known about other members within the group, what I refer to as anonymous, semi-anonymous and pseudonymous (ASAP) groups. (shrink)

Poe's Law is roughly that online parodies of religious extremism are indistinguishable from instances of sincere extremism. Poe's Law may be expressed in a variety of ways, each highlighting either a facet of indirect discourse generally, attitudes of online audiences, or the quality of online religious material. As a consequence of the polarization of online discussions, invocations of Poe's Law have relevance in wider circles than religion. Further, regular invocations of Poe's Law in critical discussions have the threat of (...) further entrenching and polarizing views. (shrink)

In the current paper, we present and discuss a series of experiments in which we investigated people’s willingness to ascribe intentions, as well as blame and praise, to groups. The experiments draw upon the so-called “Knobe Effect”. Knobe [2003. “Intentional action and side effects in ordinary language.” Analysis 63: 190–194] found that the positiveness or negativeness of side-effects of actions influences people’s assessment of whether those side-effects were brought about intentionally, and also that people are more willing to assign (...) blame for negative side-effects of actions than they are to assign praise for positive side-effect of actions. Building upon this research, we found evidence that the positiveness or negativeness of side-effects of group actions influences people’s willingness to attribute intentions to groups, and that people are more willing to assign blame to groups for negative side-effects of actions than they are to assign praise to groups for positive side-effects of... (shrink)

Much apprehension has been expressed by philosophers about the method of renormalisation in quantum field theory, as it apparently requires illegitimate procedure of infinite cancellation. This has lead to various speculations, in particular in Teller (1989). We examine Teller's discussion of perturbative renormalisation of quantum fields, and show why it is inadequate. To really approach the matter one needs to understand the ideas and results of the renormalisation group, so we give a simple but comprehensive account of this topic. (...) With this in hand, we explain how renormalisation can and should be understood. One thing that is revealed is that apparently very successful theories such as quantum electro-dynamics cannot be universally true; resolving the tension between success and falsity leads to a picture in which any theory may be viewed as irreducibly phenomenological. We explain how, and argue that the support for this view is tenuous at best. (shrink)

The principle of homophily says that people associate with other groups of people who are mostly like themselves. Many online communities are structured around groups of socially similar individuals. On Twitter, however, people are exposed to multiple, diverse points of view through the public timeline. The authors captured 30,000 tweets about the shooting of George Tiller, a late-term abortion doctor, and the subsequent conversations among pro-life and pro-choice advocates. They found that replies between like-minded individuals strengthen group identity, whereas (...) replies between different-minded individuals reinforce in-group and out-group affiliation. Their results show that people are exposed to broader viewpoints than they were before but are limited in their ability to engage in meaningful discussion. They conclude with implications for different kinds of social participation on Twitter more generally. (shrink)

In this paper, we investigate the effect described in the literature as the Group Knobe Effect, which is an asymmetry in ascription of intentionality of negative and positive side-effects of an action performed by a group agent. We successfully replicate two studies originally conducted by Michael and Szigeti, who observed this effect and provide empirical evidence of the existence of two related effects—Group Epistemic and Doxastic Knobe Effects—which show analogous asymmetry with respect to knowledge (...) and belief ascriptions. We explain how the existence of the Group Knobe Effect and its epistemic and doxastic counterparts affects the philosophical debate on collective agency and intentionality and supports the intuitiveness of realism about collective agency among laypeople. We also critically assess the reasoning presented by Michael and Szigeti in favor of the realist-collectivist interpretation of their results. We argue that a thorough analysis of both their data and our new findings shows a rather wide range of differing intuitions among laypeople regarding the status of groups as agents. These results show that while some laypeople may have realist-collectivist intuitions, the contrary realist-distrubutivist intuitions are also widespread and the claim that the majority of laypeople hold collectivist intuitions regarding group agency is unjustified. (shrink)

Various axiomatic models for unsharp quantum measurements are investigated. These include effect spaces (E-spaces), effect test spaces (E-test spaces), effect algebras, and test groups. It is shown that a test group G is the universal group of an E-test space if and only if G is strongly atomistic. It follows that if G is strongly atomistic, then G is an interpolation group. We then demonstrate that if G is an interpolation group, then G (...) is the universal group of an E-space. Finally, it is shown that an E-space is isomorphic to an E-test space if and only if it is strongly atomistic. (shrink)

In this paper we present the results of a simulation study of credence developments in groups of communicating Bayesian agents, as they update their beliefs about a given proposition p. Based on the empirical literature, one would assume that these groups of rational agents would converge on a view over time, or at least that they would not polarize. This paper presents and discusses surprising evidence that this is not true. Our simulation study shows that these groups of Bayesian agents (...) show group polarization behavior under a broad range of circumstances. This is, we think, an unexpected result, that raises deeper questions about whether the kind of polarization in question is irrational. If one accepts Bayesian agency as the hallmark of epistemic rationality, then one should infer that the polarization we find is also rational. On the other hand, if we are inclined to think that there is something epistemically irrational about group polarization, then something must be off in the model employed in our simulation study. We discuss several possible interfering factors, including how epistemic trust is defined in the model. Ultimately, we propose that the notion of Bayesian agency is missing something in general, namely the ability to respond to higher-order evidence. (shrink)

Hatred: Understanding Our Most Dangerous Emotion The first in-depth philosophical analysis of personal hate and group hate, Hate: Understanding Our Most Dangerous Emotion explores how personal hatred can foster domestic violence and emotional abuse, how hate-proneness is a main contributor to the aggressive tendencies of borderlines, narcissists and psychopaths, how seemingly ordinary people embark on some of history's worst hate crimes, and how cohesive groups, subjected to spontaneous forces of group polarization, can develop extremist viewpoints of the (...) sort that motivate hate crimes, mass shootings, and terrorism. The book's first part explores hate in intimate relationships, looking for an answer to the question of why our intimate relationships can survive hate and resentment, but not disrespect or contempt. Berit "Brit" Brogaard shows that where contempt creates an irreparable power imbalance, hate is tied to fear, which our brains may reinterpret as thrill, attraction and excitement. But this can also make hate a dangerous emotion that convinces people to hang onto abusive relationships. When tied to vengeance and the dark triad of personality, hate is not only dangerous but also dehumanizing. Vengeance and the dark personalities are not essential to hate, however. Without them, hate can have more admirable ends. The book's second part explores the polarizing forces that can bias cohesive groups of like-minded individuals and contribute to what is effectively a hate crisis. Drawing on history, politics, legal theory, philosophy, and psychology, Brogaard shows how cultural myths about femininity, ethnic groups, and the land of opportunity perpetuate misogyny, white supremacy and anti-Semitism. But, she argues, politicians and policymakers have it in their power to address the hate crisis through legislation that preserves the original incentive behind the first-amendment right to free speech. (shrink)

The notion of ecological rationality implies that the accuracy of a decision strategy depends on features of the information environment in which it is tested. We demonstrate that the performance of a group may be strongly affected by the decision strategies used by its individual members and specify how this effect is moderated by environmental features. Specifically, in a set of simulation studies, we systematically compared four decision strategies used by the individual group members: two linear, compensatory (...) decision strategies and two simple, noncompensatory heuristics. Individual decisions were aggregated by using a majority rule. To assess the ecological rationality of the strategies, we varied (a) the distribution of cue validities, (b) the quantity, and (c) the quality of shared information. Group performance strongly depended on the distribution of cue validities. When validities were linearly distributed, groups using a compensatory strategy achieved the highest accuracy. Conversely, when cue validities followed a J-shaped distribution, groups using a simple lexicographic heuristic performed best. While these effects were robust across different quantities of shared information, the quality of shared information exerted stronger effects on group performance. Consequences for prescriptive theories on group decision making are discussed. (shrink)

Poorly saturated colors are closer to a pure grey than strongly saturated ones and, therefore, appear less “colorful”. Color saturation is effectively manipulated in the visual arts for balancing conflicting sensations and moods and for inducing the perception of relative distance in the pictorial plane. While perceptual science has proven quite clearly that the luminance contrast of any hue acts as a self-sufficient cue to relative depth in visual images, the role of color saturation in such figure-ground organization has remained (...) unclear. We presented configurations of colored inducers on grey ‘test’ backgrounds to human observers. Luminance and saturation of the inducers was uniform on each trial, but varied across trials. We ran two separate experimental tasks. In the relative background brightness task, perceptual judgments indicated whether the apparent brightness of the grey test background contrasted with, assimilated to, or appeared equal (no effect) to that of a comparison background with the same luminance contrast. Contrast polarity and its interaction with color saturation affected response proportions for contrast, assimilation and no effect. In the figure-ground task, perceptual judgments indicated whether the inducers appeared to lie in front of, behind, or in the same depth with the background. Strongly saturated inducers produced significantly larger proportions of foreground effects indicating that these inducers stand out as figure against the background. Weakly saturated inducers produced significantly larger proportions of background effects, indicating that these inducers are perceived as lying behind the backgrounds. We infer that color saturation modulates figure-ground organization, both directly by determining relative inducer depth, and indirectly, and in interaction with contrast polarity, by affecting apparent background brightness. The results point towards a hitherto undocumented functional role of color saturation in the genesis of form, and in particular figure-ground percepts in the absence of chromatostereopsis. (shrink)

Experiments are presented showing that visual search for Mueller-Lyer (ML) stimuli is based on complete configurations, rather than component segments. Segments easily detected in isolation were difficult to detect when embedded in a configuration, indicating preemption by low-level groups. This preemption—which caused stimulus components to become inaccessible to rapid search—was an all-or-nothing effect, and so could serve as a powerful test of grouping. It is shown that these effects are unlikely to be due to blurring by simple spatial filters (...) at early visual levels. It is proposed instead that they are due to more sophisticated processes that rapidly bind contour fragments into spatially-extended assemblies. These results support the view that rapid visual search cannot access the primitives formed at the earliest stages of visual processing; rather, it can access only higher-level, more ecologically-relevant structures. (shrink)

The scalar approach to negative polarity item (NPI) licensing assumes that NPIs are allowable in contexts in which the introduction of the NPI leads to proposition strengthening (e.g., Kadmon & Landman 1993, Krifka 1995, Lahiri 1997, Chierchia 2006). A straightforward processing prediction from such a theory is that NPI’s facilitate inference verification from sets to subsets. Three experiments are reported that test this proposal. In each experiment, participants evaluated whether inferences from sets to subsets were valid. Crucially, we manipulated whether (...) the premises contained an NPI. In Experiment 1, participants completed a metalinguistic reasoning task, and Experiments 2 and 3 tested reading times using a self-paced reading task. Contrary to expectations, no facilitation was observed when the NPI was present in the premise compared to when it was absent. In fact, the NPI significantly slowed down reading times in the inference region. Our results therefore favor those scalar theories that predict that the NPI is costly to process (Chierchia 2006), or other, nonscalar theories (Giannakidou 1998, Ladusaw 1992, Postal 2005, Szabolcsi 2004) that likewise predict NPI processing cost but, unlike Chierchia (2006), expect the magnitude of the processing cost to vary with the actual pragmatics of the NPI. (shrink)

Several studies have lately revealed that social media conceal at least three dangerous pitfalls. Firstly, social media can negatively impact sociopolitical processes in advanced liberal democracies by becoming vehicles for the spread of false information that augments political polarization (Lee et al. 2017; Ostillio 2018). Secondly, as a result of the first point, social mediacan rapidly become a source of incorrect beliefs for those subjects with low digital literacy (Guess et al. 2019). Thirdly, because of the first and second (...) points, intentionally deceitful manipulations of social media content are potent generators of information cascades that increase group polarizations across groups of vulnerable social media users (Jang and Kim2018, Wang et al. 2018, Colliander 2019). These findings support the claim that the circulation of biased content on social media potentially threatens sociopolitical stability in liberal Western democracies (Duffy 2018; Sunstein 2018). Although this claim is far from being speculative, as shown by the FacebookFile investigations (Wall Street Journal 2019) and the center for humane technology’s recen tresearch, it introduces a thorny dilemma regarding the founding principles of liberal Western democracies. Namely, should Western legislators limit free speech by introducing severe penalties for those who spread fake news and the likes on social media? Or should they let the free market autonomously produce efficient technology allowing people to identify biased social media content?In other words, is a libertarian solution to the plight of online fake news and the like preferable to adequate legislation that punishes those who spread such content? Though appealing, it is unrealistic to believe that the free market can resolve this problem. On the other hand, it is realistic to suppose that Western governments should engage in a merciless battle against biased social media content. For instance, following the publication of the Report of the independent High level Group on fake news and online disinformation in 2018, the European Union introduced new directives to limit the spread of fake news online in 2021, when the Covid19 pandemic started fading. Although initiatives as such might look like limitations of free speech, there is solid philosophical ground to defend such initiatives. To prove this contention, we resort to Hobbes’s (1651, Part II, §18 and §29) argument that humans can avoid falling back into the Hobbesian state of war only if they stipulate a covenant. Specifically, we appeal to Hobbes’s (1651) argument in favor of bestowing the sovereign the right to ban those seditious doctrines that might undermine peace and sociopolitical stability in the Hobbesian Commonwealth. In this regard, we show that the Hobbesian covenant resolves conflict among humans in the same way a correlated equilibrium limits noncooperation in game theory. Namely, like game theory players, citizens enjoy greater welfare whenever they observe rules that mitigate conflict (Slomp 2010). Accordingly, we argue that citizens would be better off only if Western governments introduced severe penalties for those who intentionally spread fake news. Notably, we argue that effective regulation would create disincentives for spreading biased content and incentives for spreading truthful content. Furthermore, we argue that effective regulation against online fake news would assuage the polarizing effects of online availability cascades on social networks. Importantly, we provide empirical evidence supporting these claims by showing that the lack of effective regulation led the American government to miserably fail to contain the devasting effects of the online infodemic (i.e., the epidemic of false online information)that took place during the first two waves of the Covid19 pandemic (Evanega et al. 2020, Milosh et al. 2020). (shrink)

This paper explores the influence of group context on the ethical predispositions of group members. Results indicate that groups exert a powerful influence on individuals' ethical frameworks, and that the patterns of these influences differ depending on the type of ethical framework involved. Individuals' ethical utilitarianism was affected by both leadership style and group cohesiveness. Ethical formalism was most affected by the leadership style in the group.

This study uses a quasi-experimental design to investigate what happens to individual socially responsible attitudes when they are exposed to group dynamics. Findings show that group engagement increases individual attitudes toward social responsibility. We also found that individuals with low attitudes toward social responsibility are more likely to change their opinions when group members show more positive attitudes toward social responsibility. Conversely, individuals with high attitudes do not change much, independent of group characteristics. To better analyze (...) the effect of group dynamics, the study proposes to split social responsibility into relative and absolute components. Findings show that relative social responsibility is correlated with but different from absolute social responsibility although the latter is more susceptible than the former to group dynamics. (shrink)

Background: Previous studies on the effectiveness of psychological interventions in oncology mainly used quantitative measures and no study was conducted with regard to both caregivers and patients. Aim: This study evaluates the effectiveness of psychoeducational support groups, both for women with breast cancer, and for their informal caregivers through the use of quantitative and qualitative measures. Methods: A longitudinal design was used comparing two psychoeducational support groups with other two groups in a standard care control condition. Participants were 28 women (...) with a diagnosis of breast cancer in the care of a hospital in Northern Italy, and 21 family caregivers. The quantitative data were collected by Cognitive Behavioral Assessment for Outcome Evaluation (CBA-OE) and the qualitative data through the use of semi-structured interviews. Results: The statistical analysis showed a significant change attributable to the psychological intervention that proves the effectiveness of such an intervention in the patients’ and caregivers’ group. The qualitative analysis allowed us to interpret the behavioral and psychological profile emerging from CBA-OE, by considering the subjective experience of the treatment groups. The group experience offered affective, relational and informative support, and allowed participants to create a network and to feel understood and reassured. Conclusions: The results suggest the usefulness of psychoeducational support groups for women with breast cancer and for their caregivers. The value of this kind of intervention is not only at an individual level but also at a systems level, and family involvement ensures the best positive outcomes. (shrink)

Profinite groups are Galois groups. The effective study of infinite Galois groups was initiated by Metakides and Nerode [8] and further developed by LaRoche [5]. In this paper we study profinite groups without considering Galois extensions of fields. The Artin method of representing a finite group as a Galois group has been generalized by Waterhouse [14] to profinite groups. Thus, there is no loss of relevance in our approach.The fundamental notions of a co-r.e. profinite group, recursively profinite (...) group, and the degree of a co-r.e. profinite group are defined in §1. In this section we prove that every co-r.e. profinite group can be effectively represented as an inverse limit of finite groups. The degree invariant is shown to behave very well with respect to open subgroups and quotients. The work done in this section is basic to the rest of the paper.The commutator subgroup, the Frattini subgroup, thep-Sylow subgroups, and the center of a profinite group are essential in the study of profinite groups. It is only natural to ask if these subgroups are effective. The following question exemplifies our approach to this problem: Is the center a co-r.e. profinite group? Theorem 2 provides a general method for answering this type of question negatively. Examples 3,4 and 5 are all applications of this theorem. (shrink)

We investigate effective categoricity of computable Abelian p-groups . We prove that all computably categorical Abelian p-groups are relatively computably categorical, that is, have computably enumerable Scott families of existential formulas. We investigate which computable Abelian p-groups are categorical and relatively categorical.