There has recently been an explosion of formal models of signalling, which have been developed to learn about different aspects of meaning. This paper discusses whether that success can also be used to provide an original naturalistic theory of meaning in terms of information or some related notion. In particular, it argues that, although these models can teach us a lot about different aspects of content, at the moment they fail to support the idea that meaning just is some kind (...) of information. As an alternative, I suggest a more modest approach to the relationship between informational notions used in models and semantic properties in the natural world. (shrink)

Influential thinkers such as Young, Sugden, Binmore, and Skyrms have developed game-theoretic accounts of the emergence, persistence and evolution of social contracts. Social contracts are sets of commonly understood rules that govern cooperative social interaction within societies. These naturalistic accounts provide us with valuable and important insights into the foundations of human societies. However, current naturalistic theories focus mainly on how social contracts solve coordination problems in which the interests of the individual participants are aligned, not competition problems in which (...) individual interests compete with group interests. In response, I set out to build on those theories and provide a comprehensive naturalistic account of the emergence, persistence and evolution of social contracts. My central claim is that social contracts have culturally evolved to solve cooperation problems, which include both coordination and competition problems. I argue that solutions to coordination problems emerge from “within-group” dynamics, while solutions to competition problems result largely from “between-group” dynamics. (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)

Unlike any other field, the science of morality has drawn attention from an extraordinarily diverse set of disciplines. An interdisciplinary research program has formed in which economists, biologists, neuroscientists, psychologists, and even philosophers have been eager to provide answers to puzzling questions raised by the existence of human morality. Models and simulations, for a variety of reasons, have played various important roles in this endeavor. Their use, however, has sometimes been deemed as useless, trivial and inadequate. The role of models (...) in the science of morality has been vastly underappreciated. This omission shall be remedied here, offering a much more positive picture on the contributions modelers made to our understanding of morality. (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)

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.

Social contract theorists often take the ideal contract to be the agreement or bargain individuals would make in some privileged choice situation. Recently, experimental philosophers have explored this kind of decision-making in the lab. One rather robust finding is that the exact circumstances of choice significantly affect the kinds of social arrangements experimental subjects unanimously endorse. Yet prior work has largely ignored the question of which of the many competing descriptions of the original position subjects find most compelling. This paper (...) aims to address this gap, exploring how attractive experimental subjects find various characterizations of these circumstances of choice. We find evidence suggesting that no one choice situation can fulfill the role that social contract theorists have hoped it would play. We also find that, contrary to what some prominent social contract theorists have expected, there is no robust relationship between an individual’s ranking of distributive principles and their ranking of various descriptions of the original position. In conclusion, we discuss the broader implications of these results for political philosophy. (shrink)

We use game theoretic models to take an in-depth look at the dynamics of discrimination and academic collaboration. We find that in collaboration networks, small minority groups may be more likely to end up being discriminated against while collaborating. We also find that discrimination can lead members of different social groups to mostly collaborate with in-group members, decreasing the effective diversity of the social network. Drawing on previous work, we discuss how decreases in the diversity of scientific collaborations might negatively (...) affect the progress of epistemic communities. (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)

We consider modifications to the standard David Lewis signaling game and relax a number of unrealistic implicit assumptions that are often built into the framework. In particular, we motivate and explore various asymmetries that exist between the sender and receiver roles. We find that endowing receivers with a more realistic set of responses significantly decreases the likelihood of signaling, while allowing for unequal selection pressure often has the opposite effect. We argue that the results of this article can also help (...) make sense of a well-known evolutionary puzzle regarding the absence of an evolutionary arms race between sender and receiver in conflict-of-interest signaling games. (shrink)

A “sender–receiver” framework based on models developed in several fields can provide a general treatment of communicative and symbolic phenomena, replacing traditional semiotic theories that have failed to live up to the hopes of their advocates. Sender–receiver models have mostly been applied to linguistic behavior, gestures, and other ephemeral interactions between individuals. I look at the application of this framework to enduring artifacts, including pictures, using indigenous rock art in Australia as a case study.

A central goal of philosophy of perception is to uncover the nature of sensory capacities. Ideally, we would like an account that specifies what conditions need to be met in order for an organism to count as having the capacity to sense or perceive its environment. And on the assumption that sensory states are the kinds of things that can be accurate or inaccurate, a further goal of philosophy of perception is to identify the accuracy conditions for sensory states. In (...) this paper I recommend a novel approach to these core issues, one that draws heavily on game-theoretic treatments of signaling in nature. A benefit of the approach is that it helps us to understand why biologists attribute sensory powers to such a diverse range of organisms, including plants, fungi, and algae. (shrink)

Recent rapid advances in Artificial Intelligence (AI) and Machine Learning have raised many questions about the regulatory and governance mechanisms for autonomous machines. Many commentators, scholars, and policy-makers now call for ensuring that algorithms governing our lives are transparent, fair, and accountable. Here, I propose a conceptual framework for the regulation of AI and algorithmic systems. I argue that we need tools to program, debug and maintain an algorithmic social contract, a pact between various human stakeholders, mediated by machines. To (...) achieve this, we can adapt the concept of human-in-the-loop (HITL) from the fields of modeling and simulation, and interactive machine learning. In particular, I propose an agenda I call society-in-the-loop (SITL), which combines the HITL control paradigm with mechanisms for negotiating the values of various stakeholders affected by AI systems, and monitoring compliance with the agreement. In short, ‘SITL = HITL + Social Contract.’. (shrink)

Signaling games with reinforcement learning have been used to model the evolution of term languages (Lewis 1969, Convention. Cambridge, MA: Harvard University Press; Skyrms 2006, “Signals” Presidential Address. Philosophy of Science Association for PSA). In this article, syntactic games, extensions of David Lewis’s original sender–receiver game, are used to illustrate how a language that exploits available syntactic structure might evolve to code for states of the world. The evolution of a language occurs in the context of available vocabulary and syntax—the (...) role played by each component is compared in the context of simple reinforcement learning. (shrink)

In interactive situations, agents can “learn” something that is not a preexisting truth. They can converge to an arbitrary convention, or tacit agreement. Once established they may even view it as an objective truth. Here we investigate accommodation dynamics for interpersonal comparisons of utility intervals. We show, for a large class of dynamics, convergence to a convention.

In models of multi-level selection, the property of Darwinian fitness is attributed to entities at more than one level of the biological hierarchy, e.g. individuals and groups. However, the relation between individual and group fitness is a controversial matter. Theorists disagree about whether group fitness should always, or ever, be defined as total (or average) individual fitness. This paper tries to shed light on the issue by drawing on work in social choice theory, and pursuing an analogy between fitness and (...) utility. Social choice theorists have long been interested in the relation between individual and social utility, and have identified conditions under which social utility equals total (or average) individual utility. These ideas are used to shed light on the biological problem. (shrink)

Recent work by Brian Skyrms offers a very general way to think about how information flows and evolves in biological networks — from the way monkeys in a troop communicate, to the way cells in a body coordinate their actions. A central feature of his account is a way to formally measure the quantity of information contained in the signals in these networks. In this paper, we argue there is a tension between how Skyrms talks of signalling networks and his (...) formal measure of information. Although Skyrms refers to both how information flows through networks and that signals carry information, we show that his formal measure only captures the latter. We then suggest that to capture the notion of flow in signalling networks, we need to treat them as causal networks. This provides the formal tools to define a measure that does capture flow, and we do so by drawing on recent work defining causal specificity. Finally, we suggest that this new measure is crucial if we wish to explain how evolution creates information. For signals to play a role in explaining their own origins and stability, they can’t just carry information about acts: they must be difference-makers for acts. (shrink)

But as for most genes, they are not the units of interest once we get to the network level: it is the whole conspiracy we care about. Biologists, more precisely evolutionary biologists, and not only psychologists and philosophers also speak of modularity. However the way in which this theoretical construct functions in their discipline is relatively different from the role it obtains in evolutionary psychology and cognitive science. Rather than postulating modules to explain particular traits of organisms, such as the (...) specificity of input systems or limitations of human reasoning abilities, biologists originally simply assume that some form of modularity constitutes a precondition of evolution. They argue that, in order for natural selection to fine tune organisms to their environment, different traits must be able to evolve independently from one another. This implies modularity in one form or another. Organisms will only be able to adapt if they do not come all in one piece, so to speak. It must therefore be possible for changes to occur in one characteristic of an animal without those changes having repercussions throughout the whole organism. (shrink)

The concept of information has acquired a strikingly prominent role in contemporary biology. This trend is especially marked within genetics, but it has also become important in other areas, such as evolutionary theory and developmental biology, particularly where these fields border on genetics. The most distinctive biological role for informational concepts, and the one that has generated the most discussion, is in the description of the relations between genes and the various structures and processes that genes play a role in (...) causing. For many biologists, the causal role of genes should be understood in terms of their carrying information about their various products. That information might require the cooperation of various environmental factors before it can be "expressed," but the same can be said of other kinds of message. An initial response might be to think that this mode of description is entirely anchored in a set of well-established facts about the role of DNA and RNA within protein synthesis, summarized in the familiar chart representing the "genetic code," mapping DNA base triplets to amino acids. However, informational enthusiasm in biology predates even a rudimentary understanding of these mechanisms (Schrodinger 1944). And more importantly, current applications of informational concepts extend far beyond anything that can receive an obvious justification in terms of the familiar facts about the specification of protein molecules by DNA. This includes: 1 (i) The description of whole-organism phenotypic traits (including complex behavioral traits) as specified or coded for by information contained in the genes, (ii) The treatment of many causal processes within cells, and perhaps of the wholeorganism developmental sequence, in terms of the execution of a program stored in the genes, (iii) The idea that genes themselves, for the purpose of evolutionary theorizing, should be seen as, in some sense, "made" of information.. (shrink)

Robustness analysis is widespread in science, but philosophers have struggled to justify its confirmatory power. We provide a positive account of robustness by analysing some explicit and implicit uses of within and across-model robustness in evolutionary theory. We argue that appeals to robustness are usually difficult to justify because they aim to increase the likeliness that a phenomenon obtains. However, we show that robust results are necessary for explanations of phenomena with specific properties. Across-model robustness is necessary for how-possibly explanations (...) of multiply instantiated phenomena, while within-model robustness is necessary for explanations of phenomena with multiple evolutionary starting points. In such cases, the appeal of robustness is explanatory rather than confirmatory. (shrink)

What is the function of morality? On this question, something approaching a consensus has recently emerged. Impressed by developments in evolutionary theory, many philosophers now tell us that the function of morality is to reduce social tensions, and to thereby enable a society to efficiently promote the well-being of its members. In this paper, I subject this consensus to rigorous scrutiny, arguing that the functional hypothesis in question is not well supported. In particular, I attack the supposed evidential relation between (...) an evolutionary genealogy of morals and the functional hypothesis itself. I show that there are a great many functionally relevant discontinuities between our own culture and the culture within which morality allegedly emerged, and I argue that this seriously weakens the inference from morality’s evolutionary history to its present-day function. (shrink)

In a recent article, Gauthier rejects orthodox rational choice contractarianism in favor of a revisionist approach to the social contract that, according to him, justifies his principle of maximin proportionate gain as a principle of distributive justice. I agree with Gauthier that his principle of maximin proportionate gain cannot be justified by orthodox rational choice contractarianism. I argue, however, that orthodox rational choice contractarianism, before and after Gauthier, is still a viable approach to the social contract, although the scope of (...) this approach is limited. Orthodox rational choice contractarianism can be applied fruitfully to moral philosophy only in situations of deep moral pluralism in which moral reasoning is reduced to instrumental reasoning, because the members of society do not share, as assumed by traditional moral theories, a consensus on moral ideals as traditionally conceived as a starting point for the derivation of moral rules but only an overarching end that they aim to reach. If orthodox rational choice contractarianism is applied adequately, then it offers a viable approach to the social contract that, in contrast to Gauthier’s theory, justifies a rival principle for distributive conflicts that is valid for deeply morally pluralistic societies. (shrink)

According to the dominant view, the later Wittgenstein identified the meaning of an expression with its use in the language and vehemently rejected any kind of mentalism or intentionalism about linguistic meaning. I argue that the dominant view is wrong. The textual evidence, which has either been misunderstood or overlooked, indicates that at least since the Blue Book Wittgenstein thought speakers' intentions determine the contents of linguistic utterances. His remarks on use are only intended to emphasize the heterogeneity of natural (...) language. Taking into account remarks written after he finished the Investigations, I show how Wittgenstein anticipated the basic tenets of Gricean intention-based semantics. These are, in particular, the distinction between ‘natural’ and ‘non-natural’ meaning and the distinction between what a speaker means by an utterance and what the expression uttered means in the speaker’s natural language. Importantly, Wittgenstein also believed that only the meaning of the speaker determined the content of ambiguous expressions, such as ‘bank’, on a particular occasion of utterance. (shrink)

Collaboration is increasingly popular across academia. Collaborative work raises certain ethical questions, however. How will the fruits of collaboration be divided? How will the work for the collaborative project be split? In this paper, we consider the following question in particular. Are there ways in which these divisions systematically disadvantage certain groups? -/- We use evolutionary game theoretic models to address this question. First, we discuss results from O'Connor and Bruner (unpublished). In this paper, we show that underrepresented groups in (...) academia can be disadvantaged in such situations by dint of their small numbers. Second, we present novel results exploring how the hierarchical structure of academia can lead to bargaining disadvantage. We investigate models where one actor has a higher baseline of academic success, less to lose if collaboration goes south, or greater rewards for non-collaborative work. We show that in these situations, the less powerful partner is disadvantaged in bargaining over collaboration. (shrink)

In this commentary, I review diverse lines of research conducted at both the macrosocial and microbehavioral level that dispute the view that cruelty is inherently gratifying. Expressions of pain and suffering typically inhibit rather than reinforce cruel conduct in humans. With regard to functional value, cruelty has diverse personal and social effects, not just the alluring benefits attributed to it.

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)

The philosopher David Lewis is credited by many social scientists, including mainstream economists, with having founded the modern (game-theoretical) approach to conventions, viewed as solutions to recurrent coordination problems. Yet it is generally ignored that he revised his approach, soon after the publication of his well-known book. I suggest that this revision has deep implications (probably not perceived by Lewis himself) on the analytical links between coordination, uncertainty and rationality. Thinking anew about these issues leads me to map out an (...) alternative social scientific research programme. The traditional ontological equipment of methodological individualism should be reinforced in order to admit the existence of an “intersubjective” world beside the two familiar worlds: the “objective” world of observable things, and the “subjective” world of expectations and individual beliefs. In particular, language becomes necessary to understand coordination via conventions, rather than the other way round. That has led a group of institutionalist economists and pragmatist sociologists to develop an enlarged model of rationality, no longer isolated from questions of coordination and values. This model is the basis for the “Economics of Conventions”. (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)

Sender–receiver games, first introduced by David Lewis ([1969]), have received increased attention in recent years as a formal model for the emergence of communication. Skyrms ([2010]) showed that simple models of reinforcement learning often succeed in forming efficient, albeit not necessarily minimal, signalling systems for a large family of games. Later, Alexander et al. ([2012]) showed that reinforcement learning, combined with forgetting, frequently produced both efficient and minimal signalling systems. In this article, I define a ‘dynamic’ sender–receiver game in which (...) the state–action pairs are not held constant over time and show that neither of these two models of learning learn to signal in this environment. However, a model of reinforcement learning with discounting of the past does learn to signal; it also gives rise to the phenomenon of linguistic drift. 1 Introduction2 Dynamic Signalling Games with Reinforcement Learning2.1 Introducing new states2.2 Swapping state–action pairs3 Discounting the Past3.1 Learning to signal in a dynamic world3.2 An unexpected outcome: linguistic drift4 ConclusionAppendix: A Markov Chain Analysis. (shrink)

The goal of philosophy of information is to understand what information is, how it operates, and how to put it to work. But unlike ‘information’ in the technical sense of information theory, what we are interested in is meaningful information. To understand the nature and dynamics of information in this sense we have to understand meaning. What we offer here are simple computational models that show emergence of meaning and information transfer in randomized arrays of neural nets. These we take (...) to be formal instantiations of a tradition of theories of meaning as use. What they offer, we propose, is a glimpse into the origin and dynamics of at least simple forms of meaning and information transfer as properties inherent in behavioral coordination across a community. (shrink)

Ethological theories usually attribute semantic content to animal signals. To account for this fact, many biologists and philosophers appeal to some version of teleosemantics. However, this picture has recently came under attack: while mainstream teleosemantics assumes that representational systems must cooperate, some biologists and philosophers argue that in certain cases signaling can evolve within systems lacking common interest. In this paper I defend the standard view from this objection.

We extend previous work on cooperation to some related questions regarding the evolution of simple forms of communication. The evolution of cooperation within the iterated Prisoner's Dilemma has been shown to follow different patterns, with significantly different outcomes, depending on whether the features of the model are classically perfect or stochastically imperfect (Axelrod 1980a, 1980b, 1984, 1985; Axelrod and Hamilton, 1981; Nowak and Sigmund, 1990, 1992; Sigmund 1993). Our results here show that the same holds for communication. Within a simple (...) model, the evolution of communication seems to require a stochastically imperfect world. (shrink)

This paper is interested in the relationship between evolutionary thinking and moral behavior and commitments, ethics. There is a traditional way of forging or conceiving of the relationship. This is traditional evolutionary ethics, known as Social Darwinism. Many think that this position is morally pernicious, a redescription of the worst aspects of modern, laissez-faire capitalism in fancy biological language. It is argued that, in fact, there is much more to be said for Social Darwinism than many think. In respects, it (...) could be and was an enlightened position to take; but it flounders on the matter of justification. Universally, the appeal is to progress—evolution is progressive and, hence, morally we should aid its success. I argue, however, that this progressive nature of evolution is far from obvious and, hence, traditional social Darwinism fails. There is another way to do things. This is to argue that the search for justification is mistaken. Ethics just is. It is an adaptation for humans living socially and has exactly the same status as other adaptations, like hands and teeth and genitalia. As such, ethics is something with no standing beyond what it is. However, if we all thought that this was so, we would stop being moral. So part of the experience of ethics is that it is more than it is. We think that it has an objective referent. In short, ethics is an illusion put in place by our genes to make us good social cooperators. (shrink)

A computer simulation runs a model generating a phenomenon under investigation. For the simulation to be explanatory, the model has to be explanatory. The model must be isomorphic to the natural system that realizes the phenomenon. This paper elaborates the method of assessing a simulation's explanatory power. Then it illustrates the method by applying it to two simulations in game theory. The first is Brian Skyrms's (1990) simulation of interactive deliberations. It is intended to explain the emergence of a Nash (...) equilibrium in a noncooperative game. The second is Skyrms's (2004) simulation of the evolution of cooperation. It is intended to explain cooperation in assurance games. The final section suggests ways of enhancing the explanatory power of these simulations. (shrink)

We study a low-rationality learning dynamics called probe and adjust. Our emphasis is on its properties in games of information transfer such as the Lewis signaling game or the Bala-Goyal network game. These games fall into the class of weakly better reply games, in which, starting from any action profile, there is a weakly better reply path to a strict Nash equilibrium. We prove that probe and adjust will be close to strict Nash equilibria in this class of games with (...) arbitrarily high probability. In addition, we compare these asymptotic properties to short-run behavior. (shrink)

In The Order of Public Reason (2011a), Gerald Gaus rejects the instrumental approach to morality as a viable account of social morality. Gaus' rejection of the instrumental approach to morality, and his own moral theory, raise important foundational questions concerning the adequate scope of instrumental morality. In this article, I address some of these questions and I argue that Gaus' rejection of the instrumental approach to morality stems primarily from a common but inadequate application of this approach. The scope of (...) instrumental morality, and especially the scope of pure moral instrumentalism, is limited. The purely instrumental approach to morality can be applied fruitfully to moral philosophy only in situations of extreme pluralism in which moral reasoning is reduced to instrumental reasoning, because the members of a society do not share, as assumed by traditional moral theories, a consensus on moral ideals as a basis for the derivation of social moral rules, but only an end that they aim to reach. Based on this understanding, I develop a comprehensive two-level contractarian theory that integrates traditional morality with instrumental morality. I argue that this theory, if implemented, is most promising for securing mutually beneficial peaceful long-term cooperation in deeply pluralistic societies, as compared to cooperation in a non-moralized state of nature. (shrink)

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

Kin selection, reciprocity and group selection are widely regarded as evolutionary mechanisms capable of sustaining altruism among humans andother cooperative species. Our research indicates, however, that these mechanisms are only particular examples of a broader set of evolutionary possibilities.In this paper we present the results of a series of simple replicator simulations, run on variations of the 2–player prisoner's dilemma, designed to illustrate the wide range of scenarios under which altruism proves to be robust under evolutionary pressures. The set of (...) mechanisms we explore is divided into four categories :correlation, group selection, imitation, and punishment. We argue that correlation is the core phenomenon at work in all four categories. (shrink)

Since at least as long ago as Plato’s time, philosophers have considered the possibility that justice is at bottom a system of rules that members of society follow for mutual advantage. Some maintain that justice as mutual advantage is a fatally flawed theory of justice because it is too exclusive. Proponents of a Vulnerability Objection argue that justice as mutual advantage would deny the most vulnerable members of society any of the protections and other benefits of justice. I argue that (...) the Vulnerability Objection presupposes that in a justice-as-mutual-advantage society only those who can and do contribute to the cooperative surplus of benefits that compliance with justice creates are owed any share of these benefits. I argue that justice as mutual advantage need not include such a Contribution Requirement. I show by example that a justice-as-mutual-advantage society can extend the benefits of justice to all its members, including the vulnerable who cannot contribute. I close by arguing that if one does not presuppose a Contribution Requirement, then a justice-as-mutual-advantage society might require its members to extend the benefits of justice to humans that some maintain are not persons (for example, embryos) and to certain nonhuman creatures. I conclude that the real problem for defenders of justice as mutual advantage is that this theory of justice threatens to be too inclusive. (shrink)

Group selection is one acknowledged mechanism for the evolution of altruism. It is well known that for altruism to spread by natural selection, interactions must be correlated; that is, altruists must tend to associate with one another. But does group selection itself require correlated interactions? Two possible arguments for answering this question affirmatively are explored. The first is a bad argument, for it rests on a product/process confusion. The second is a more subtle argument, whose validity (or otherwise) turns on (...) issues concerning the meaning of multi-level selection and how it should be modelled. A cautious defence of the second argument is offered. Introduction Multi-level selection and the evolution of altruism Price's equation and multi-level selection Contextual analysis and multi-level selection The neighbour approach Recapitulation and conclusion. (shrink)

Does rational bargaining yield a social contract that is efficient and so inclusive? A core allocation, that is, an allocation that gives each coalition at least as much as it can get on its own, is efficient. However, some coalitional games lack a core allocation, so rationality does not require one in those games. Does rationality therefore permit exclusion from the social contract? I replace realization of a core allocation with another type of equilibrium achievable in every coalitional game. Fully (...) rational agents coordinate the pursuit of incentives so that equilibria of this type are efficient. They adopt a social contract that is efficient and inclusive. (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)