In February 2020, the British Society for the History of Science hosted its first entirely digital conference via Twitter, with the dual goals of improving outreach and engagement with international historians of science, and exploring methods of reducing the carbon footprint of academic activities. In this article we discuss how we planned and organized this conference, and provide a summary of our experience of the conference itself. We also describe in greater detail the motivations behind its organization, and explore the (...) good and bad dimensions of this relatively new kind of conferencing. As the climate crisis becomes more acute and, in turn, the pressure to reduce the carbon footprint of academic activities increases, we argue that digital conferences of this style will necessarily become more central to how academia operates. By sharing our own experiences of running such a conference, we seek to contribute to a rapidly growing body of knowledge on the subject that might be drawn on to improve our practices going forward. We also share some of our own ideas about how best to approach digital conference organization which helped us to make the most of this particular event. (shrink)

Abstract Some philosophers find linguistic meaning mysterious. Two approaches suggest themselves for removing the felt mystery, or demystifying meaning. One involves providing a substantive account of meaning in meaning-free terms. Although this approach has come under serious attack in recent years, Paul Horwich has recently presented a version of the approach that might be thought impervious. A preliminary attempt is made to argue that Horwich's version is vulnerable to the considerations felt to undermine other versions of the substantive approach to (...) demystification. That leaves the second approach, quietism, which involves showing that although meaning is primitive it is un-mysterious. It is suggested that this approach is worthy of exploration. (shrink)

In this paper we discuss how Causal Decision Theory should be modified to handle a class of problematic cases involving deterministic laws. Causal Decision Theory, as it stands, is problematically biased against your endorsing deterministic propositions (for example it tells you to deny Newtonian physics, regardless of how confident you are of its truth). Our response is that this is not a problem for Causal Decision Theory per se, but arises because of the standard method for assessing the truth of (...) certain counterfactuals. The truth of deterministic laws is `modally fragile' on the standard semantics for counterfactuals: if determinism is true and you were to do otherwise, the laws would be different. We provide two ways of avoiding this problem: 1) supplement the standard semantics for counterfactuals with impossible worlds, or 2) introduce rigid designators into the description of problematic decision situations. We argue that both of these approaches are well-motivated and can be readily incorporated into Lewisian Causal Decision Theory. (shrink)

This paper suggests that art cannot be defined in terms of individually necessary and jointly sufficient conditions. Instead, we propose that there are several sufficient conditions for something's being art, and that a successful definition will consist of a disjunction of minimally sufficient conditions. Our proposal owes much to the insights of Berys Gaut's ‘“Art” as a Cluster Concept’ but offers a much simpler logical formulation, which, in addition, is immune to the objections that have been raised to Gaut's account. (...) This paper agrees with Gaut's claim that there are borderline cases of art, and suggests that they arise from indeterminacy about the content of some of the minimally sufficient conditions. It is argued that this disjunctive account is superior to classical theories, resemblance-to-paradigm theories, and prototype theories of art. (shrink)

I discuss the conjecture that understanding what is said in an utterance is to be modelled as knowing what is said in that utterance. My main aim is to present a number of alter- native models, as a prophylactic against premature acceptance of the conjecture as the only game in town. I also offer preliminary assessments of each of the models, including the propositional knowledge model, in part by considering their respective capacities to sub-serve the transmission of knowledge through testimony. (...) In each case, the preliminary assessment is unfavourable. I end by very briefly sketching an additional model as an object for future consideration. (shrink)

Two sources of possible disagreement in bioethics may be associated with pessimism about what bioethics can achieve. First, pluralism implies that bioethics engages with interlocutors who hold divergent moral beliefs. Pessimists might believe that these disagreements significantly limit the extent to which bioethics can provide normatively robust guidance in relevant areas. Second, the interdisciplinary nature of bioethics suggests that interlocutors may hold divergent views on the nature of bioethics itself—particularly its practicality. Pessimists may suppose that interdisciplinary disagreements could frustrate the (...) goals of bioethics. In this article, I explore how wonder may alleviate the concerns of the first group of pessimists regarding problems associated with pluralism, provided that we are willing to accept some interdisciplinary frustrations. Then, I invite readers of this issue of The Journal of Medicine & Philosophy to test these intuitions by considering the role of wonder in these articles. (shrink)

This book engages Christian love theologies, feminist economics, and political theory to identify elements of a Christian ethic of dependent care relations.

In the paper, a detailed analysis of some new logical aspects of Cantor’s diagonal proof of the uncountability of continuum is presented. For the first time, strict formal, axiomatic, and algorithmic definitions of the notions of potential and actual infinities are presented. It is shown that the actualization of infinite sets and sequences used in Cantor’s proof is a necessary, but hidden, condition of the proof. The explication of the necessary condition and its factual usage within the framework of Cantor’s (...) proof makes, Cantor’s proof invalid. It’s shown that traditional Cantor’s proof has a second necessary, but hidden as well, condition which is teleological by its nature, i.e., is not mathematical. The explication of the second necessary condition makes Cantor’s statement on the uncountability of continuum unprovable from the point of view of classical logic.One of the most dramatic facts in history of science is connected just with the notion of actual infinity and consists in the following. On the one hand, Aristotle, Berkeley, Locke, Descartes, Spinoza, Gauss, Kant, Cauchy, Kronecker, Hermite, Poincaré, Bair, Borel, Brouwer, Quine, Wittgenstein, Weyl, Luzin, and a lot of other outstanding creators of classical logic and classical mathematics, during millenniums, stated categorically and insistently warned about that the actual infinity is a self-contradictory notion and its usage in mathematics is inadmissible (e.g., according to Poincare, “There is no actual infinity. - Cantorians forgot that and fell into contradictions. Later generations will regard Mengenlehre (set theory) as a disease from which one has recovered”). On the other hand, a lot of outstanding scientists of the XX c.c., such as Hilbert, Church, Turing, Gödel, etc., and modern axiomatic set theory as a whole ignored this (intuitive though) opinion of genii and accepted Cantor’s “transfinite paradise”, based on the actual infinity. In the paper some logical, philosophical, and psychological aspects of this historical “favorable opposition” are analyzed, and the fact that the scientific intuition of genii has won the historical battle against the mytho-’logic’ of Cantor’s transfinite ‘paradise’ is explained and logically justified. (shrink)

In the paper, a detailed analysis of some new logical aspects of Cantor’s diagonal proof of the uncountability of continuum is presented. For the first time, strict formal, axiomatic, and algorithmic definitions of the notions of potential and actual infinities are presented. It is shown that the actualization of infinite sets and sequences used in Cantor’s proof is a necessary, but hidden, condition of the proof. The explication of the necessary condition and its factual usage within the framework of Cantor’s (...) proof makes, Cantor’s proof invalid. It’s shown that traditional Cantor’s proof has a second necessary, but hidden as well, condition which is teleological by its nature, i.e., is not mathematical. The explication of the second necessary condition makes Cantor’s statement on the uncountability of continuum unprovable from the point of view of classical logic.One of the most dramatic facts in history of science is connected just with the notion of actual infinity and consists in the following. On the one hand, Aristotle, Berkeley, Locke, Descartes, Spinoza, Gauss, Kant, Cauchy, Kronecker, Hermite, Poincaré, Bair, Borel, Brouwer, Quine, Wittgenstein, Weyl, Luzin, and a lot of other outstanding creators of classical logic and classical mathematics, during millenniums, stated categorically and insistently warned about that the actual infinity is a self-contradictory notion and its usage in mathematics is inadmissible (e.g., according to Poincare, “There is no actual infinity. - Cantorians forgot that and fell into contradictions. Later generations will regard Mengenlehre (set theory) as a disease from which one has recovered”). On the other hand, a lot of outstanding scientists of the XX c.c., such as Hilbert, Church, Turing, Gödel, etc., and modern axiomatic set theory as a whole ignored this (intuitive though) opinion of genii and accepted Cantor’s “transfinite paradise”, based on the actual infinity. In the paper some logical, philosophical, and psychological aspects of this historical “favorable opposition” are analyzed, and the fact that the scientific intuition of genii has won the historical battle against the mytho-’logic’ of Cantor’s transfinite ‘paradise’ is explained and logically justified. (shrink)

The various themes explored in this superb collection of essays are organised around one thinker, John McDowell, and one central idea.

John Cook Wilson is an important predecessor of contemporary knowledge first epistemologists: among other parallels, he claimed that knowledge is indefinable. We reconstruct four arguments for this claim discernible in his work, three of which find no clear analogues in contemporary discussions of knowledge first epistemology. We pay special attention to Cook Wilson’s view of the relation between knowledge and forms of thinking (like belief). Claims of Cook Wilson’s that support the indefinability of knowledge include: that knowledge, unlike belief, straddles (...) an active/passive divide; that, rather than entailing belief, knowledge excludes belief; and that understanding forms of thinking other than knowledge (such as belief) depends on understanding knowledge. Reflecting on Cook Wilson’s framework highlights underappreciated concerns relevant to any attempt to define knowledge. (shrink)

Mental causation is notoriously threatened by the causal exclusion argument. A prominent strategy to save mental causation from causal exclusion consists in subscribing to an interventionist account of causation. This move has, however, recently been challenged by several authors. In this paper, we do two things: We (i) develop what we consider to be the strongest version of the interventionist causal exclusion argument currently on the market and (ii) propose a new way how it can in principle be overcome. In (...) particular, we propose to replace strict supervenience in the assumption that the mental supervenes on the physical by probabilistic supervenience and show how this move has the potential to license the inference to mental causation. Finally, we argue that probabilistic supervenience captures some of the most important intuitions that strict supervenience captures and discuss possible objections to weakening strict supervenience in the way we suggest. (shrink)

Contemporary recognition of the importance of divisions amongst pragmatic and semantic phenomena has its roots in earlier recognition of the importance of pragmatic phenomena. This chapter begins with the idea that semantics concerns the stable meanings of words and expressions while pragmatics concerns language use, or things done with words. It provides some grounds for rejecting, a defense of orthodoxy that sought to treat the variations that Charles Travis highlights as occurring only with respect to derivative illocutionary acts. The chapter (...) argues that the orthodox view comes under pressure from reflection on certain forms of variation in the illocutionary acts that speakers perform. It explores how the meanings of the words that the speaker used, which figure most directly in the locutionary act that they performed, figure less directly in the illocutionary act or acts that they perform, and less directly still in the further, perlocutionary consequences of the performance of that illocutionary act. (shrink)

Protestant Christian ethicist Timothy Jackson and secular feminist philosopher Eva Feder Kittay each explore the relationship between love or care and justice through the lens of human dependency. Jackson sharply prioritizes agape over justice, whereas Kittay articulates a more complex and integrated understanding of the relationship of care and distributive justice. An account of Christian love and its relation to justice must account for the gratuity, mutuality, and reciprocity that pervade human existence. Such an account must integrate provision for another's (...) basic needs, a feature of agape, with a distributive justice that fairly allocates the material prerequisites of care and the burden of caring labor. Kittay's treatment of care and justice is more adequate to the realities of human embodiment and the social organization of care than Jackson's, but neither offers a fully adequate ground for the moral personhood of all human beings, including deeply dependent persons. (shrink)

A new speculative ontology of aesthetics. In Aesthesis and Perceptronium, Alexander Wilson presents a theory of materialist and posthumanist aesthetics founded on an original speculative ontology that addresses the interconnections of experience, cognition, organism, and matter. Entering the active fields of contemporary thought known as the new materialisms and realisms, Wilson argues for a rigorous redefining of the criteria that allow us to discriminate between those materials and objects where aesthesis (perception, cognition) takes place and those where it doesn't. (...) Aesthesis and Perceptronium negotiates between indiscriminately pluralist views that attribute mentation to all things and eliminative views that deny the existence of mentation even in humans. By recasting aesthetic questions within the framework of "epistemaesthetics," which considers cognition and aesthetics as belonging to a single category that can neither be fully disentangled nor fully reduced to either of its terms, Wilson forges a theory of nonhuman experience that avoids this untenable dilemma. Through a novel consideration of the evolutionary origins of cognition and its extension in technological developments, the investigation culminates in a rigorous reevaluation of the status of matter, information, computation, causality, and time in terms of their logical and causal engagement with the activities of human and nonhuman agents. (shrink)

THE RECENT CONVERSATION WITHIN CHRISTIAN ETHICS ABOUT THE RELAtionship between universal obligations and particular, intensive relations—between agape and "special relations"—largely accepts Gene Outka's formulation that these are separate and competing moral claims that must be balanced within the Christian moral life. I examine the relationship between agape and special relations through the lens of dependency and dependent-care relations. Attention to dependent care and the material needs addressed within them raises questions about the sharp division between universal and particular obligations. Drawing (...) on the work of feminist philosopher Eva Feder Kittay, I argue that an adequate understanding of Christian love must take account of both our fundamental human equality and the pervasiveness of dependency in human life. Such an understanding of Christian love reveals that agape is a matter of personal and social ethics. (shrink)

Since World War II, US Catholic anti-abortion discourse has been framed in term of rights-language, ascribing civil and human rights to the prenate from the moment of conception. Yet many of those who would criminalize abortion have allied with anti-democratic political movements that buttress White supremacy and threaten civil rights. This contradiction exposes the theoretical inadequacy and epistemological hubris of current Catholic abortion discourse. While the Catholic Church and individual Catholics may subscribe to absolute moral norms against abortion, they should (...) not leverage rights-language to legislate such norms in a pluralistic democracy. Instead, Catholics should draw on our rich tradition of virtuous practical reasoning for an abortion ethic that honors the moral agency of pregnant persons and democratic citizens. (shrink)

The purpose of the two studies reported here was to develop an integrated model of the scientific reasoning process. Subjects were placed in a simulated scientific discovery context by first teaching them how to use an electronic device and then asking them to discover how a hitherto unencountered function worked. To do this task, subjects had to formulate hypotheses based on their prior knowledge, conduct experiments, and evaluate the results of their experiments. In the first study, using 20 adult subjects, (...) we identified two main strategies that subjects used to generate new hypotheses. One strategy was to search memory and the other was to generalize from the results of previous experiments. We described the former group as searching an hypothesis space, and the latter as searching an experiment space. In a second study, with 10 adults, we investigated how subjects search the hypothesis space by instructing them to state all the hypotheses that they could think of prior to conducting any experiments. Following this phase, subjects were then allowed to conduct experiments. Subjects who could not think of the correct rule in the hypothesis generation phase discovered the correct rule only by generalizing from the results of experiments in the experimental phase.Both studies provide support for the view that scientific reasoning can be characterized as search in two problem spaces. By extending Simon and Lea's (1974) Generalized Rule Inducer, we present a general model of Scientific Discovery as Dual Search (SDDS) that shows how search in two problem spaces (an hypothesis space and an experiment space) shapes hypothesis generation, experimental design, and the evaluation of hypotheses. The model also shows how these processes interact with each other. Finally, we interpret earlier findings about the psychology of scientific reasoning in terms of the SDDS model. (shrink)

Group size is a function of relative neocortical volume in nonhuman primates. Extrapolation from this regression equation yields a predicted group size for modern humans very similar to that of certain hunter-gatherer and traditional horticulturalist societies. Groups of similar size are also found in other large-scale forms of contemporary and historical society. Among primates, the cohesion of groups is maintained by social grooming; the time devoted to social grooming is linearly related to group size among the Old World monkeys and (...) apes. To maintain the stability of the large groups characteristic of humans by grooming alone would place intolerable demands on time budgets. It is suggested that (1) the evolution of large groups in the human lineage depended on the development of a more efficient method for time-sharing the processes of social bonding and that (2) language uniquely fulfills this requirement. Data on the size of conversational and other small interacting groups of humans are in line with the predictions for the relative efficiency of conversation compared to grooming as a bonding process. Analysis of a sample of human conversations shows that about 60% of time is spent gossiping about relationships and personal experiences. It is suggested that language evolved to allow individuals to learn about the behavioural characteristics of other group members more rapidly than is possible by direct observation alone. (shrink)

Is linguistic understanding a form of knowledge? I clarify the question and then consider two natural forms a positive answer might take. I argue that, although some recent arguments fail to decide the issue, neither positive answer should be accepted. The aim is not yet to foreclose on the view that linguistic understanding is a form of knowledge, but to develop desiderata on a satisfactory successor to the two natural views rejected here.

In lieu of an abstract, here is a brief excerpt of the content:Reviewed by:Erotic Attunement: Parenthood and the Ethics of Sensuality between Unequals by Cristina L. H. TrainaSandra Sullivan-DunbarErotic Attunement: Parenthood and the Ethics of Sensuality between Unequals CRISTINA L. H. TRAINA Chicago: University of Chicago Press, 2011, 363 pp. $55.00In this ambitious and broadly interdisciplinary work, Cristina Traina begins from an experience that evades contemporary discussion: maternal sensual pleasure in the care of infants and young children. As Traina notes, (...) this experience puts two contemporary dogmas on a “collision course”: the widely accepted norm that sexual pleasure is intrinsically good and the widely accepted norm that sexual pleasure between unequals is intrinsically exploitative. As with other feminist turns toward neglected experience, this one calls for a recalibration of ethical models—in this case, a more complex and nuanced sexual ethic.Traina challenges readers to broaden notions of sexuality beyond androcentric models focused primarily on particular acts and on genital release. Such models are deeply graven in the Christian tradition and reinforced through reductive cultural appropriations of Freudian thought. But all human relations are embodied and involve desire, argues Traina, and are thus in some sense erotic, though most do not involve genital sexuality. Likewise, her readers are challenged to recognize the pervasiveness of relations of inequality in human life, when most Christian sexual ethics limit themselves to relations between equals, or at least understand a sexual ethic to aim at equality and mutuality.The book engages psychological resources demonstrating the human need for appropriate touch as well as the profound damage done by abusive touch. The need is so universal and foundational that Traina casts it as a human right; yet offering such touch appropriately is a subtle and challenging moral task beset with danger and the potential for self-deception.Traina diagnoses the sexual abuser as a fragmented self, one unable to perceive the concrete reality, needs, and experiences of her victim and bent on the doomed project of creating a whole self by appropriating and objectifying the other. Thus, at the heart of her ethic of sensuality between unequals is the notion of “attunement.” The attuned caregiver can acknowledge and fully experience inclinations, joys, and pains with a contemplative and compassionate awareness that allows considered and appropriate responses. The attuned care-giver lives with “unending, acknowledged desire” (177), a desire that glories in the goodness of the child in her care and, in so doing, creatively elicits subjectivity from her rather than manipulating her to meet the needs of the caregiver. [End Page 240]This ethical vision is developed in dialogue with a number of resources from Christian and secular sources. Traina helpfully nuances a Thomistic account of the virtue of temperance as a guideline for appropriate touch. She also develops revisionist accounts of Augustinian desire offered by Wendy Farley and Linda Holler. I found myself wondering whether some more traditional interpretations of Augustine might serve Traina’s project as well as or better than these revisionist understandings, which emphasize desire as a permanent state rather than directed toward final rest in God.Likewise, Traina works her way through the plethora of recent eros theologies, drawing in particular on recent interpretations of Plato’s Symposium that stress the creativity of eros in bringing to birth goodness and beauty as well as its potential for enabling a degree of other-regard. It seems to this reader that a contemporary ethic of sexuality between unequals calls for greater other-regard than the most generous interpretation of Plato’s ladder of love can suggest. However, Plato’s caution about the profound difficulty of directing eros toward the true good resonates with the difficulty of achieving the “erotic attunement” described by Traina.In any case, quibbles about the resources and interpretations that Traina mines to support her ethic do not lessen the originality, power, and importance of this book, which extends beyond sexual ethics to reframe questions about embodiment, (in)equality, and moral agency in profound and necessary ways.Sandra Sullivan-DunbarLoyola University, ChicagoCopyright © 2014 Society of Christian Ethics... (shrink)

On the most prominent account, understanding what was said is always propositional knowledge of what was said. I develop a more minimal alternative, according to which understanding is sometimes a distinctive attitude towards what was said—to a first approximation, entertaining what was said. The propositional knowledge account has been supported on the basis of its capacity to explain testimonial knowledge transmission. I argue that it is not so supported.

This paper is about first‐person thoughts—thoughts about oneself that are expressible through uses of first‐person pronouns. It is widely held that first‐person thoughts cannot be shared. My aim is to postpone rejection of the more natural view that such thoughts about oneself can be shared. I sketch an account on which such thoughts can be shared and indicate some ways in which deciding the fate of the account will depend upon further work.

Can knowledge be defined? We expound an argument of John Cook Wilson's that it cannot. Cook Wilson's argument connects knowing with having the power to inquire. We suggest that if he is right about that connection, then knowledge is, indeed, indefinable.

To what extent was ordinary language philosophy a precursor to experimental philosophy? Since the conditions on pursuit of either project are at best unclear, and at worst protean, the general question is hard to address. I focus instead on particular cases, seeking to uncover some central aspects of J. L. Austin’s and John Cook Wilson’s ordinary language based approach to philosophical method. I make a start at addressing three questions. First, what distinguishes their approach from other more traditional approaches? Second, (...) is their approach a form of experimental philosophy? Third, given their aims, should it have been? I offer the following preliminary answers. First, their approach distinctively emphasizes attention to what we should say when. Second, their approach is closer to contemporary experimental mathematics than it is to some prominent forms of contemporary experimental philosophy. Third, some purported grounds for pursuing their aims by way of surveying what individual speakers would say when are not compelling. (shrink)

What are the connections between the successful performance of illocutionary acts and audience understanding or uptake of their performance? According to one class of proposals, audience understanding suffices for successful performance. I explain how those proposals emerge from earlier work and seek to clarify some of their interrelations.

First published in 2000. Routledge is an imprint of Taylor & Francis, an informa company.

Are there distinctively second-personal thoughts? I clarify the question and present considerations in favour of a view on which some second-personal thoughts are distinctive. Specifically, I suggest that some second-personal thoughts are distinctive in also being first-personal thoughts. Thus, second-personal thinking provides a way of sharing another person's first-personal thoughts.

The purpose of the two studies reported here was to develop an integrated model of the scientific reasoning process. Subjects were placed in a simulated scientific discovery context by first teaching them how to use an electronic device and then asking them to discover how a hitherto unencountered function worked. To do this task, subjects had to formulate hypotheses based on their prior knowledge, conduct experiments, and evaluate the results of their experiments. In the first study, using 20 adult subjects, (...) we identified two main strategies that subjects used to generate new hypotheses. One strategy was to search memory and the other was to generalize from the results of previous experiments. We described the former group as searching an hypothesis space, and the latter as searching an experiment space. In a second study, with 10 adults, we investigated how subjects search the hypothesis space by instructing them to state all the hypotheses that they could think of prior to conducting any experiments. Following this phase, subjects were then allowed to conduct experiments. Subjects who could not think of the correct rule in the hypothesis generation phase discovered the correct rule only by generalizing from the results of experiments in the experimental phase.Both studies provide support for the view that scientific reasoning can be characterized as search in two problem spaces. By extending Simon and Lea's (1974) Generalized Rule Inducer, we present a general model of Scientific Discovery as Dual Search (SDDS) that shows how search in two problem spaces (an hypothesis space and an experiment space) shapes hypothesis generation, experimental design, and the evaluation of hypotheses. The model also shows how these processes interact with each other. Finally, we interpret earlier findings about the psychology of scientific reasoning in terms of the SDDS model. (shrink)

The target article aims to bridge the gap between secularized Buddhist theory and practical neuroethical matters through dialogue with Tibetan Buddhist monastics centered upon questions of personal...

For a novice this book is a mathematically-oriented introduction to modal logic, the discipline within mathematical logic studying mathematical models of reasoning which involve various kinds of modal operators. It starts with very fundamental concepts and gradually proceeds to the front line of current research, introducing in full details the modern semantic and algebraic apparatus and covering practically all classical results in the field. It contains both numerous exercises and open problems, and presupposes only minimal knowledge in mathematics. A specialist (...) can use the book as a source of references. Results and methods of many directions in propositional modal logic, from completeness and duality to algorithmic problems, are collected and systematically presented in one volume. (shrink)

First published in 2000. Routledge is an imprint of Taylor & Francis, an informa company.

Hyperlink cinema is an emergent film genre that seeks to push the boundaries of the medium in order to mirror contemporary life in the globalized community. Films in the genre thus create an interacting network across space and time in such a way as to suggest that people’s lives can intersect on scales that would not have been possible without modern technologies of travel and communication. This allows us to test the hypothesis that new kinds of media might permit us (...) to break through the natural cognitive constraints that limit the number and quality of social relationships we can manage in the conventional face-to-face world. We used network analysis to test this hypothesis with data from 12 hyperlink films, using 10 motion pictures from a more conventional film genre as a control. We found few differences between hyperlink cinema films and the control genre, and few differences between hyperlink cinema films and either the real world or classical drama (e.g., Shakespeare’s plays). Conversation group size seems to be especially resilient to alteration. It seems that, despite many efficiency advantages, modern media are unable to circumvent the constraints imposed by our evolved psychology. (shrink)

This paper examines social network size in contemporary Western society based on the exchange of Christmas cards. Maximum network size averaged 153.5 individuals, with a mean network size of 124.9 for those individuals explicitly contacted; these values are remarkably close to the group size of 150 predicted for humans on the basis of the size of their neocortex. Age, household type, and the relationship to the individual influence network structure, although the proportion of kin remained relatively constant at around 21%. (...) Frequency of contact between network members was primarily determined by two classes of variable: passive factors (distance, work colleague, overseas) and active factors (emotional closeness, genetic relatedness). Controlling for the influence of passive factors on contact rates allowed the hierarchical structure of human social groups to be delimited. These findings suggest that there may be cognitive constraints on network size. (shrink)