I offer an explanation for why certain sequences of decisions strike us as irrational while others do not. I argue that we have a standing desire to tell flattering yet plausible narratives about ourselves, and that cases of diachronic behavior that strike us as irrational are those in which you had the opportunity to hide something unflattering and failed to do so.

In large, impersonal moral orders many of us wish to maintain good will toward our fellow citizens only if we are reasonably sure they will maintain good will toward us. The mutual maintaining of good will, then, requires that we somehow communicate our intentions to one another. But how do we actually do this? The current paper argues that when we engage in moral responsibility practices—that is, when we express our reactive attitudes by blaming, praising, and resenting—we communicate a desire (...) to maintain good will to those in the community we are imbedded in. Participating in such practices alone will not get the job done, though, for expressions of our reactive attitudes are often what economists call cheap talk. But when we praise and blame in cases of moral diversity, expressions of our reactive attitudes act as costly signals capable of solving our social dilemma. (shrink)

Recently, philosophers have drawn on tools from game theory to explore behavior in Hobbes’ state of nature. I take a similar approach and argue the Lockean state of nature is best conceived of as a conflictual coordination game. I also discuss Nozick’s famous claim regarding the emergence of the state and argue the path to the minimal state is blocked by a hitherto unnoticed free-rider problem. Finally, I argue that on my representation of the Lockean state of nature both widespread (...) conflict and lasting peace are possible. This, I contend, is in line with one popular interpretation of Locke. (shrink)

Understanding Institutions offers a theory that is able to unify the two dominant approaches in the scientific and philosophical literature on institutions. Moreover, using the ‘rules-in-equilibrium’ theory, it tackles several ancient puzzles in the philosophy of social science.

Evolutionary debunking arguments appeal to selective etiologies of human morality in an attempt to undermine moral realism. But is morality actually the product of evolution by natural selection? Although debunking arguments have attracted considerable attention in recent years, little of it has been devoted to whether the underlying evolutionary assumptions are credible. In this paper, we take a closer look at the evolutionary hypotheses put forward by two leading debunkers, namely Sharon Street and Richard Joyce. We raise a battery of (...) considerations, both empirical and theoretical, that combine to cast doubt on the plausibility of both hypotheses. We also suggest that it is unlikely that there is in the vicinity a plausible alternative hypothesis suitable for the debunker’s cause. (shrink)

Some unpleasant emotions, like fear and disgust, appear straightforwardly susceptible to evolutionary explanation on account of the benefits they seem to provide to individuals. But guilt is more puzzling in this respect. Like other unpleasant emotions, guilt is often associated with a host of negative effects on the individual, such as psychological suffering and social withdrawal. Moreover, many guilt-induced behaviors, such as revealing one’s offenses and placing oneself before the mercy of others, could levy a cost to individuals that is (...) not outweighed by guilt’s benefits. Supposing there is an evolutionary story to tell about the origins of guilt, the question is how such negative effects were sufficiently outweighed by the potential fitness payoffs that guilt might have yielded to individuals. In this article, we consider which forms of evolution could have resulted in guilt, and whether current evidence can tell us which form of evolution most likely occurred. (shrink)

I introduce an extension of the Lewis-Skyrms signaling game, analysed from a dynamical perspective via simple reinforcement learning. In Lewis’ (Convention, Blackwell, Oxford, 1969) conception of a signaling game, salience is offered as an explanation for how individuals may come to agree upon a linguistic convention. Skyrms (Signals: evolution, learning & information, Oxford University Press, Oxford, 2010a) offers a dynamic explanation of how signaling conventions might arise presupposing no salience whatsoever. The extension of the atomic signaling game examined here—which I (...) will refer to as a salience game—introduces a variable parameter into the atomic signaling game which allows for degrees of salience, thus filling in the continuum between Skyrms’ and Lewis’ models. The model does not presuppose any salience at the outset, but illustrates a process by which accidentally evolved salience is amplified, to the benefit of the players. It is shown that increasing degrees of salience allow populations to avoid sub-optimal pooling equilibria and to coordinate upon conventions more quickly. (shrink)

The paper puts forward a new skeptical solution to Kripke’s Wittgenstein’s rule-following paradox, a solution which revolves around the idea that human communication does not require meaning facts - at least as defined by Kripke. After a brief discussion of the paradox, I explain why I think that Kripkenstein’s solution needs revision and argue that the main goal of a skeptical solution to the rule-following paradox should be that of showing that communication does not require meaning. After that, I offer (...) two arguments for the thesis that communication does not require meaning. The first argument instantiates a rather direct strategy and focuses on the description of a concrete case of communication without meaning. The second one is more indirect in that I start by describing a world in which, although there are meaning facts, communication does not depend on them. The paper’s last section deals with the issue of meaning talk. (shrink)

According to the socio-cognitive revolution hypothesis, humans but not other great apes acquire language because only we possess the socio-cognitive abilities required for Gricean communication, which is a pre-requisite of language development. On this view, language emerged only following a socio-cognitive revolution in the hominin lineage that took place after the split of the Pan-Homo clade. In this paper, I argue that the SCR hypothesis is wrong. The driving forces in language evolution were not sweeping biologically driven changes to hominin (...) social cognition. Our LCA with non-human great apes was likely already a Gricean communicator, and what came with evolution was not a raft of new socio-cognitive abilities, but subtle tweaks to existing ones. It was these tweaks, operating in conjunction with more dramatic ecological changes and a significant increase in general processing power, that set our ancestors on the road to language. (shrink)

This paper is a partial review of the literature on ‘social preferences'. There are empirical findings that convincingly demonstrate the existence of social preferences, but there are also studies that indicate their fragility. So how robust are social preferences, and how exactly are they context dependent? One of the most promising insights from the literature, in my view, is an equilibrium explanation of mutually referring conditional social preferences and expectations. I use this concept of equilibrium, summarized by means of a (...) figure, to discuss a range of empirical studies. Where appropriate, I also briefly discuss a couple of insights from the (mostly parallel) evolutionary literature about cooperation. A concrete case of the Orma in Kenya will be used as a motivating example in the beginning. (shrink)

The handicap principle stipulates that signal reliability can be maintained if signals are costly to produce. Yet empirical biologists are typically unable to directly measure evolutionary costs, and instead appeal to expenditure as a sensible proxy. However the link between expenditure and cost is not always as straightforward as proponents of HP assume. We consider signaling interactions where whether the expenditure associated with signaling is converted into an evolutionary cost is in some sense dependent on the behavior of the intended (...) recipient of the signal. We illustrate this with a few empirical examples and demonstrate that on this alternative expenditure to cost mapping the traditional predictions of HP no longer hold. Instead of full information transfer, a partially informative communication system like those uncovered by Wagner :163–181, 2013) and Zollman et al. is possible. (shrink)

Here I discuss the philosophical contributions to Analytical Sociology and Social Mechanisms, a collection of essays edited by Pierre Demeulenaere. I begin by introducing the idea of a social mechanism and showing that it has already had an impact within empirical analytical sociology. I then discuss some examples of the philosophical work offered in Demeulenaere’s collection in support of this analytical “movement” in the social sciences. I argue that some of these examples demonstrate thin scholarship and only a veneer of (...) philosophical argument, but that Jon Elster’s contribution fuses impressively philosophical analysis and social science. I conclude by suggesting that analytical sociologists should focus on producing sociological explanations not philosophical theories. (shrink)

In A Darwinian left Peter Singer aims to reconcile Darwinian theory with left wing politics, using evolutionary game theory and in particular a model proposed by Robert Axelrod, which shows that cooperation can be an evolutionarily successful strategy. In this paper I will show that whilst Axelrod’s model can give support to a kind of left wing politics, it is not the kind that Singer himself envisages. In fact, it is shown that there are insurmountable problems for the idea of (...) increasing Axelrodian cooperation within a welfare state. My surprising conclusion will be that a Darwinian left worthy of the name would be anarchistic. Ó 2005 Elsevier Ltd. All rights reserved. (shrink)

Current debates in social ontology are dominated by approaches that view institutions either as rules or as equilibria of strategic games. We argue that these two approaches can be unified within an encompassing theory based on the notion of correlated equilibrium. We show that in a correlated equilibrium each player follows a regulative rule of the form ‘if X then do Y’. We then criticize Searle's claim that constitutive rules of the form ‘X counts as Y in C’ are fundamental (...) building blocks for institutions, showing that such rules can be derived from regulative rules by introducing new institutional terms. Institutional terms are introduced for economy of thought, but are not necessary for the creation of social reality. (shrink)

Philosophers and social scientists have recently turned to game theory and agent-based models to better understand social contract formation. The stag hunt game is an idealization of social contract formation. Using the stag hunt game, we attempt to determine what, if any, barrier diversity is to the formation of an efficient social contract. We uncover a deep connection between tolerance, diversity, and the social contract. We investigate a simple model in which individuals possess salient traits and behave cooperatively when the (...) difference between their trait and the trait of their counterpart is less than their ‘tolerance level’. If traits are fixed and correspond to permanent or semipermanent features of the individual, such as religion or race, social contract formation is a remote possibility. If traits are malleable, social contract formation is possible but comes at the steep cost of diversity and tolerance, that is, individuals are unwilling to cooperate with those much different from themselves. Yet homogeneity and intolerance are not a long-term feature of the population. Over time mutations allow for increasingly tolerant agents to prosper, thereby ushering in trait diversity. In the end, all reap the benefits of cooperation. (shrink)

Epicurean contractarianism is an attempt to reconcile individualistic hedonism with a robust account of justice. The pursuit of pleasure and the requirements of justice, however, have seemed to be incompatible to many commentators, both ancient and modern. It is not clear how it is possible to reconcile hedonism with the demands of justice. Furthermore, it is not clear why, even if Epicurean contractarianism is possible, it would be necessary for Epicureans to endorse a social contract. I argue here that Epicurean (...) contractarianism is both possible and necessary once we understand Epicurean practical rationality in a new way. We are left with an appealing version of teleological, individualistic contractarianism that is significantly different from Hobbesian contractarianism. (shrink)

1 Logic in philosophy The century that was Logic has played an important role in modern philosophy, especially, in alliances with philosophical schools such as the Vienna Circle, neopositivism, or formal language variants of analytical philosophy. The original impact was via the work of Frege, Russell, and other pioneers, backed up by the prestige of research into the foundations of mathematics, which was fast bringing to light those amazing insights that still impress us to-day. The Golden Age of the 1930s (...) deeply affected philosophy, and heartened the minority of philosophers with a formalanalytical bent. As Brand Blanshard writes in Reason and Analysis (1964) – I quote from memory here, to avoid the usual disappointment when re-reading an original text. (shrink)

Both the quantity of information and the informational content of a signal are defined in the context of signaling games. Informational content is a generalization of standard philosophical notions of propositional content. It is shown how signals that initially carry no information may spontaneously acquire informational content by evolutionary or learning dynamics. It is shown how information can flow through signaling chains or signaling networks.

David Lewis’ Convention has been a major source of inspiration for philosophers and social scientists alike for the analysis of norms. In this essay, I demonstrate its usefulness for the analysis of some moral norms. At the same time, conventionalism with regards to moral norms has attracted sustained criticism. I discuss three major strands of criticism and propose how these can be met. First, I discuss the criticism that Lewis conventions analyze norms in situations with no conflict of interest, whereas (...) most, if not all, moral norms deal with situations with conflicting interests. This criticism can be answered by showing that conventions can emerge in those contexts as well. Secondly, I discuss the objection that this type of conventionalism, inspired by Lewis, presents moral norms as fundamentally contingent, whereas most, if not all, moral norms are not. However, such critics fail to appreciate that conventions are not radically contingent. Moreover, if one distinguishes the question as to why an individual should comply with a norm from the question whether the norm in question itself can be justified, a core element of the complaint of contingency disappears. The third objection to conventionalism concerns the way in which conventionalists justify norms. I argue that reflection upon the way in which according to Lewis norms are justified reveals a fundamental tension in his theory. Possible solutions to this tension all have in common that the complaint of contingency returns in some form. Therefore, this third complaint cannot be avoided altogether. (shrink)

Do conventions need to be common knowledge in order to work? David Lewis builds this requirement into his definition of a convention. This paper explores the extent to which his approach finds support in the game theory literature. The knowledge formalism developed by Robert Aumann and others militates against Lewis’s approach, because it shows that it is almost impossible for something to become common knowledge in a large society. On the other hand, Ariel Rubinstein’s Email Game suggests that coordinated action (...) is no less hard for rational players without a common knowledge requirement. But an unnecessary simplifying assumption in the Email Game turns out to be doing all the work, and the current paper concludes that common knowledge is better excluded from a definition of the conventions that we use to regulate our daily lives. (shrink)

The central claim of my paper is that pragmatics has a wider scope of application than has been generally appreciated. In particular, I will argue that many discussions of pragmatics are guilty of a problematic form of provincialism. The provincialism at issue restricts the class of target systems of study to those involving groups of developmentally typical humans (or slightly idealized versions thereof), either explicitly as a matter of principle or implicitly as consequence of how it construes the underlying pragmatic (...) notions. In what follows, I will argue that this kind of provincialism is problematic because there are patterns of non-human animal social interaction that cannot be properly explained without recourse to the theoretical tool-kit of pragmatics. Crucially, rejecting provincialism about pragmatics does not entail that there are not important theoretical differences between human and non-human systems of pragmatics. It does, however, require that our core philosophical theories of social interaction and communication be centered on features independent not merely of those at work in human languages but also of uniquely human features of cognition and sociality more generally. (shrink)

John Rawls’s most mature notion of political order is “stability for the right reasons.” Stability for the right reasons is the kind of political order that Rawls hoped a well-ordered society could ideally achieve. In this paper, I demonstrate through the tools of modern game theory, the instability of “stability for the right reasons.” Specifically, I will show that a well-ordered society can completely destabilize by the introduction of an arbitrarily small number of non- compliers whenever individuals fail to achieve (...) full common knowledge ever so slightly. (shrink)

Current empirical studies of moral behavior of healthcare professionals are almost entirely focused on self-reports, usually collected under the assumption that an ethical disposition characterizes individuals across various contexts. It is well known, however, that individuals adjust their behavior to what they see being done by those in their peer group. That presents a methodological challenge to traditional research within a community of peers because the behavior of each individual is both the result of norms and a contributor to the (...) norms of others. Computer simulations can be used to address this methodological challenge. A Markov replicator model that runs on an Excel spreadsheet was used to investigate a community with four agent types in the dental community: devious practitioners, ethical practitioners who avoid involvement in the poor ethics of others, ethical practitioners who accept it as part of their professional responsibility to challenge colleagues who act unprofessionally, and those who enforce ethical standards. A panel of leaders in the profession independently estimated parameters for the model and criteria for a possible distribution of agent types in the community. The simulation converged on distributions of the agent types that were very similar to the expectations of the panel. The simulation suggests the following characteristics of such moral communities: The structure of such communities is robust across a wide distribution. It appears that reduction in unethical behavior is more sensitive to the way ethical practitioners interact with each other than to sanctions the enforcement community imposes on unethical practitioners, and that large external interventions will be short lived. (shrink)

The human faculty of moral judgment is not well suited to address problems, like climate change, that are global in scope and remote in time. Advocates of ‘moral bioenhancement’ have proposed that we should investigate the use of medical technologies to make human beings more trusting and altruistic, and hence more willing to cooperate in efforts to mitigate the impacts of climate change. We survey recent accounts of the proximate and ultimate causes of human cooperation in order to assess the (...) prospects for bioenhancement. We identify a number of issues that are likely to be significant obstacles to effective bioenhancement, as well as areas for future research. (shrink)

Using evolutionary game theory, I consider how guilt can provide individual fitness benefits to actors both before and after bad behavior. This supplements recent work by philosophers on the evolution of guilt with a more complete picture of the relevant selection pressures.

In this article I develop a big picture of the evolution of human cooperation, and contrast it to an alternative based on group selection. The crucial claim is that hominin history has seen two major transitions in cooperation, and hence poses two deep puzzles about the origins and stability of cooperation. The first is the transition from great ape social lives to the lives of Pleistocene cooperative foragers; the second is the stability of the social contract through the early Holocene (...) transition to complex hierarchical societies. The first of these transitions is driven, at least initially, by individual advantage: cooperation paid off for individual foragers, initially through mutualist interaction, then through reciprocation. This argument leads to a reanalysis of the role of violence and the nature of the freeriding threat to cooperation. But the conditions that select for cooperative individuals in the Pleistocene were eroded in the Pleistocene–Holocene transition. So we need an alternative account of the survival, and indeed the expansion, of cooperation in the Holocene. Group selection driven by intercommunal conflict really may well be central to this second transition. (shrink)

Using results from evolutionary game theory, we analyze the conditions under which guilt can provide individual fitness benefits to actors, and so evolve. In particular, we focus on the individual benefits of guilty apology. We find that guilty apology is more likely to evolve in cases where actors interact repeatedly over long periods of time, where the costs of apology are low or moderate, and where guilt is hard to fake.

The problem of trust is discussed in terms of David Hume’s meadow-draining example. This is analyzed in terms of rational choice, evolutionary game theory and a dynamic model of social network formation. The kind of explanation that postulates an innate predisposition to trust is seen to be unnecessary when social network dynamics is taken into account.

Natural languages are compositional in that the meaning of complex expressions depends on those of the parts and how they are put together. Here, I ask the following question: why are languages compositional? I answer this question by extending Lewis–Skyrms signaling games with a rudimentary form of compositional signaling and exploring simple reinforcement learning therein. As it turns out: in complex worlds, having compositional signaling helps simple agents learn to communicate. I am also able to show that learning the meaning (...) of a function word, once meanings of atomic words are known, presents no difficulty. (shrink)

This article presents a community-based account of salience as an alternative and a complement to the ‘natural salience’ approach which is endorsed by almost all game theorists who use this concept. While in the naturalistic approach, salience is understood as an objective and natural property of some entities, the community-based account claims that salience is a function of community membership. Building on David Lewis’s theory of common knowledge and on some of its recent refined accounts, I suggest that salience acts (...) as a correlating device in a correlated equilibrium. What is constitutive of salience is common understanding, the fact that agents have common knowledge that they share the same modes of reasoning with respect to a well-identified set of events. I argue that the basis for common understanding is community membership. The relevance of this account stems from the fact that it answers the objection that salience is either unnecessary or unable to account for coordination between rational agents. (shrink)

One approach to moral economy wishes to show that it is rational to be moral. As rational morality has received little attention from economics, as opposed to political philosophy, this article examines it in an economics framework. Rational morality refers primarily to individual behaviour so that one may also speak of it as moral microeconomics. When a group of agents are disposed to constrain their maximisation, that behaviour may be considered rational. However, this relies on ‘moralised’ assumptions about individual behaviour. (...) Constrained maximisation may also rely on repeated interactions within social structures that then transmit information thus serving as enforcement mechanisms. In this way agents obtain knowledge of others’ past behaviour and choose their interlocutors accordingly. Thus, it pays to behave morally as it will attract similarly disposed agents to participate in cooperative ventures for mutual advantage. An analysis of rational morality on the individual level demonstrates how this.. (shrink)

We apply spatialized game theory and multi-agent computational modeling as philosophical tools: (1) for assessing the primary social psychological hypothesis regarding prejudice reduction, and (2) for pursuing a deeper understanding of the basic mechanisms of prejudice reduction.

Helen Frowe has recently offered what she calls a “practical” account of self-defense. Her account is supposed to be practical by being subjectivist about permissibility and objectivist about liability. I shall argue here that Frowe first makes up a problem that does not exist and then fails to solve it. To wit, her claim that objectivist accounts of permissibility cannot be action-guiding is wrong; and her own account of permissibility actually retains an objectivist (in the relevant sense) element. In addition, (...) her attempt to restrict subjectivism primarily to “urgent” situations like self-defense contradicts her own point of departure and is either incoherent or futile. Finally, the only actual whole-heartedly objectivist account she criticizes is an easy target; while those objectivist accounts one finds in certain Western European jurisdictions are immune to her criticisms. Those accounts are also clearly superior to hers in terms of action-guidingness. (shrink)

John Rawls's transition from A Theory of Justice to Political Liberalism was driven by his rejection of Theory's account of stability. The key to his later account of stability is the idea of public reason. We see Rawls's account of stability as an attempt to solve a mutual assurance problem. We maintain that Rawls's solution fails because his primary assurance mechanism, in the form of public reason, is fragile. His conception of public reason relies on a condition of consensus that (...) we argue is unrealistic in modern, pluralistic democracies. After rejecting Rawls's conception of public reason, we offer an ‘indirect alternative’ that we believe is much more robust. We cite experimental evidence to back up this claim. (shrink)

Australasian Journal of Philosophy, Volume 90, Issue 1, Page 192-195, March 2012.

Dov Gabbay is a prolific logician just by himself. But beyond that, he is quite good at making other people investigate the many further things he cares about. As a result, King's College London has become a powerful attractor in our field worldwide. Thus, it is a great pleasure to be an organizer for one of its flagship events: the Augustus de Morgan Workshop of 2005. Benedikt Loewe and I proposed the topic of 'interactive logic' for this occasion, with an (...) emphasis on social software – the logical analysis and design of social procedures – and on games, arguably the formal interactive setting par excellence. This choice reflects current research interests in our logic community at ILLC Amsterdam and beyond. In this broad area of interfaces between logic, computer science, and game theory, this paper is my own attempt at playing Dov. I am, perhaps not telling, but at least asking other people to find out for me what I myself cannot. (shrink)

This paper applies the theoretical criteria laid out by D’Arms et al. to various aspects of evolutionary models of signalling. The question that D’Arms et al. seek to answer can be formulated as follows: Are the models that we use to explain the phenomena in question conceptually adequate? The conceptual adequacy question relates the formal aspects of the model to those aspects of the natural world that the model is supposed to capture. Moreover, this paper extends the analysis of D’Arms (...) et al. by asking the following additional question: Are the models that we use sufficient to explain the phenomena in question? The sufficiency question asks what formal resources are minimally required for the model to get the right results most of the time. (shrink)

Traditionally, epistemologists have distinguished between epistemic and pragmatic goals. In so doing, they presume that much of game theory is irrelevant to epistemic enterprises. I will show that this is a mistake. Even if we restrict attention to purely epistemic motivations, members of epistemic groups will face a multitude of strategic choices. I illustrate several contexts where individuals who are concerned solely with the discovery of truth will nonetheless face difficult game theoretic problems. Examples of purely epistemic coordination problems and (...) social dilemmas will be presented. These show that there is a far deeper connection between economics and epistemology than previous appreciated. (shrink)

The evolution of color categorization systems is investigated by simulating categorization games played by a population of artificial agents. The constraints placed on individual agent’s perception and cognition are minimal and involve limited color discriminability and learning through reinforcement. The main dynamic mechanism for population evolution is pragmatic in nature: There is a pragmatic need for communication between agents, and if the results of such communications have positive consequences in their shared world then the agents involved are positively rewarded, whereas (...) if the results have negative consequences, then involved agents are punished. A mechanism for changing the composition of the population due to agents’ birth and death is also investigated. This birth-death mechanism is found to effectively move an established population color naming system toward a theoretically more optimal one. The simulation results of this article provide insights regarding mechanisms that may constrain universal tendencies in human color categorization systems observed in the linguistic and anthropological literatures. (shrink)

So-called evolutionary error theorists, such as Michael Ruse and Richard Joyce, have argued that naturalistic accounts of the moral sentiments lead us to adopt an error theory approach to morality. Roughly, the argument is that an appreciation of the etiology of those sentiments undermines any reason to think that they track moral truth and, furthermore, undermines any reason to think that moral truth actually exists. I argue that this approach offers us a false dichotomy between error theory and some form (...) of moral realism. While accepting the presuppositions of the evolutionary error theorist, I argue that contract-based approaches to morality can be sensitive to those presuppositions while still vindicating morality. Invoking Stephen Darwall’s distinction between contractualism and contractarianism, I go on to offer an evolutionary-based contractarianism. (shrink)

In this article, I derive a weak version of Kant's categorical imperative within an informal game-theoretic framework. More specifically, I argue that Hobbesian agents would choose what I call the weak principle of universalization, if they had to decide on a rule of conflict resolution in an idealized but empirically defensible hypothetical decision situation. The discussion clarifies (i) the rationality requirements imposed on agents, (ii) the empirical conditions assumed to warrant the conclusion, and (iii) the political institutions that are necessary (...) to implement the derived principle. The analysis demonstrates the moral significance of the weak principle of universalization and its epistemic advantage over the categorical imperative. (shrink)

The structuring of our environment to provide cues and reminders for ourselves is common: We leave notes on the fridge, we have a particular place for our keys where we deposit them, making them easy to find. We alter our world to streamline our cognitive tasks. But how did hominins gain this capacity? What pushed our ancestors to structure their physical environment in ways that buffered thinking and began the process of using the world cognitively? I argue that the capacity (...) to engage in these behaviours is a by-product of increased tool investment and tool curation, which in turn was necessary because of increasingly heterogeneous environments. The minute tools are carried and cared for, they begin to undergo selection for added functions, becoming available as cognitive primers and as signals. I explore the trajectory of this co-evolutionary feedback loop of hominins and their tools, and demonstrate the role tools have in shaping our thinking. (shrink)

Evolutionary researchers argue that religion evolves to support cooperation, where it is assumed that cooperation is threatened by freeriding. I identify a distinct threat to cooperation from uncertainty. I briefly explain how the distinction between freeriding and uncertainty is relevant to both ultimate and proximate explanations of the biocultural mechanisms that express religious traits.

Intersectionality theory explores the special sorts of disadvantage that arise as the result of occupying multiple disadvantaged demographic categories. One significant methodological problem for the quantitative study of intersectionality is the difficulty of acquiring data sets large enough to produce significant results when one is looking for intersectional effects. For this reason, we argue, simulation methods may be particularly useful to this branch of theorizing because they can generate precise predictions and causal dependencies in a relatively cheap way, and can (...) thus guide future empirical work. We illustrate this point through models which show that intersectional oppression can arise under conditions where social groups are disadvantaged in the emergence of bargaining norms. As we show, intersectional disadvantage can arise even when actors from all social categories are completely identical in terms of preferences and abilities. The conditions necessary to derive such disadvantage are relatively minimal. And when actors behave in ways that reflect stronger intersectional identities, the potential for disadvantage increases. (shrink)

We argue that conceptual analyses of collective action should be informed by game-theoretic analyses of collective action. In particular, we argue that Ariel Rubenstein’s so-called ‘Electronic Mail Game’ provides a useful model of collective action, and of the formation of collective intentions.

Group-structured populations, of the kind prominent in discussions of multilevel selection, are contrasted with ‘neighbor-structured’ populations. I argue that it is a necessary condition on multilevel description of a selection process that there should be a nonarbitrary division of the population into equivalence classes (or an approximation to this situation). The discussion is focused via comparisons between two famous problem cases involving group structure (altruism and heterozygote advantage) and two neighbor-structured cases that resemble them. Conclusions are also drawn about the (...) role of correlated interaction in the evolution of altruism. 1 Introduction 2 Two Kinds of Population Structure 3 Objections and Replies 4 Particles on a Line 5 Conclusion Appendix: Neighborhoods and Selection CiteULike Connotea Del.icio.us What's this? (shrink)

Hobbes’s own justification for the existence of governments relies on the assumption that, without a government, our lives in the state of nature would result in a state of war of every man against every man. Many contemporary scholars have tried to explain why universal war is unavoidable in Hobbes’s state of nature by utilizing modern game theory. However, most game-theoretic models that have been presented so far do not accurately capture what Hobbes deems to be the primary cause of (...) conflict in the state of nature – which is uncertainty, rather than people’s egoistic psychology. Any game- theoretic model that does not incorporate uncertainty into the picture is, therefore, I claim, the wrong model. In this paper, I use Bayesian game-theory to show how universal conflict can break-out in the state of nature - even when the majority of the population would strictly prefer to cooperate and seek peace with other people - due to uncertainty about the other person’s type. Along the way, I show that the valuation of one’s own life is one of the central mechanisms that drives Hobbes’s pessimistic conclusion. (shrink)