Workshops

Cultural Evolution at the Santa Fe Institute

Last May, Daniel Dennett gathered, at the Santa Fe Institute, a handful of people who have written about cultural evolution. The general impression was that (as he tweeted some time later) "the meeting revealed a lot of unexpected comon ground". The International Cognition and Culture Institute is happy to publish, by way of proceedings, each participant's summary. Comments are open!

Daniel Dennett's introduction (with comments).

Participants' summaries (in alphabetical order): Susan BlackmoreRobert BoydNicolas ClaidièrePeter Godfrey-SmithJoseph HenrichOlivier MorinPeter RichersonDan SperberKim Sterelny.

(We gratefully acknowledge the generous support of Louis Godbout, which made the meeting possible.)

Olivier Morin

These are Olivier Morin's remarks on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BlackmoreBoydClaidièreGodfrey-SmithHenrichRichersonSperberSterelny. 

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Here is my 200% subjective summary of the main points of agreement (and some disagreements) touched upon in our (to me quite unforgettable) workshop.

On memes and replicators

There seems to be a consensus (although I am sometimes not sure whether to include Blackmore in it) on several points:

— « Let's be Darwinian about Darwinism » (Dennett). Darwinian evolution should not be essentialized, there are vast grey areas between boundary cases and ideal Darwinian populations. In that spirit, we can make room for creative anticipation and transformation in our views of cultural evolution. Memes, like other scientific notions, can survive a radical re-thinking of the theory they first served to advertize: « I want to let the word "meme" go the way the words "atom" and "gene" went: de-Darwinize it! » (Dennett)

— Both transformation and selection drive cultural evolution. We dont know what their respective weights are (and the answer probably varies quite a lot from situation to situation) but there are reasons to think that these weights contribute to cultural evolution in an additive way: the less of one, the more of the other. Also, the proportion of transformation vs. replication determines what area we are in in Godfrey-Smith's space.

Kim Sterelny

These are Kim Sterelny's thoughts (written up at mid-workshop) on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BlackmoreBoydClaidièreGodfrey-SmithHenrichMorinRichersonSperber.

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Santa Fe Summary: Key Issues From Discussion

1.Attraction and selection. What is the relationship between the SMC attractor based framework, and the BRH approach, which prima facie finds a more obvious role for selection and adaptation, especially cumulative adaptation. While the SMC group do not deny the existence of examples of adaptive complexity, their discussion and models are not organised around these kinds of cases. In the discussion, I tried out one way of seeing how the two approaches might fit together, borrowing from the saner versions of evo-devo: see the mechanisms identified in the SMC approach as constraints and biases in the supply of variation to selection-like processes. Except in extreme cases where those constraints reduce the supply of variation to a trickle (as in C’s zebra finch case, we the experimental set up exposes the hatchling to a single model) that can still leave plenty of work for selection-like forces. I take it the SMC suggestion was to see the attractor-approach as more general than selectionist approaches, which for them come out as a special form of attraction. That seems to me to obscure an important distinction between the supply of variation and its fate. But maybe M’s suggestion does not fit that evo-devo picture, seeing he focuses on downstream constraints that affect success rate (on whether a cultural variant is a flop). But what is the difference between that and selection (selection often depends on factors internal to a lineage, as in the relationship between sexual selection and sensory biases).

Rob Boyd

These is the beginning of Robert Boyd's thoughts on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Boyd's full text, because it contains mathematical symbols, is in PDF format and is accessible here. Dennett's introduction is here. Click to see other summaries by BlackmoreClaidière, Godfrey-SmithHenrichMorinRichersonSperberSterelny.

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Some thoughts about things I learned at Dan Dennett's excellent party

I have been thinking about the relationship between the kind of models that Pete, Joe and I have made and the ECM framework sketched by Dan and Nicolas in their paper. In particular, I have trying to understand how the mechanistic processes represented in our approach relate to homo-hetero distinction central to the ECM approach. In my remarks on Sue Blackmore's papers I sketched a simple model in which there were two variants with a selection stage and a transformation stage. So, rst I'd like to convert this model to the ECM framework developed by Sperber and Cladiere.

More here

Joseph Henrich

These are Joseph Henrich's thoughts on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BlackmoreBoydClaidièreGodfrey-SmithMorinRichersonSperberSterelny. 

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Based on our five days of discussion, I tried to come up with a list of stuff we agree on:

1. Cultural evolution is a crucial phenomenon for understanding humans (at least). It’s a worthy goal to develop a broad framework for thinking and studying cultural evolution.

2. Natural selection has shaped human minds in ways that have a big impact on cultural evolution.

3. Some of these reliably developing psychological products of natural selection can usefully be thought of as adaptations for effectively learning from others, which include content-rich mechanisms that facilitate inferential reconstruction during cultural transmission as well as mechanisms that help learners select those members of their social world most likely to possess useful stuff to learn. Workshop members varied on how important or interesting these different elements were, but everyone seemed happy to get down to the business of sorting out when, where and how much. What we need is a large body of empirical work on specific cases.

Susan Blackmore

These are Susan Blackmore's thoughts on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BoydClaidièreGodfrey-SmithHenrichMorinRichersonSperberSterelny. 

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There was much agreement at the wonderful working party in Santa Fe. For example, we agreed about the importance of re-production, reconstruction, teaching and demonstration as well as true imitation. I loved DS’s T-shirt folding video, but concluded that the variety and complexity of these processes does not detract from the fact that the folded T-shirt and the skill of folding it are memes that are passed on and selfishly compete with other variants.

We all agreed that there is always a leash (if have previously implied that the memes could entirely escape, I would now suggest this is only possible in the digital world of temes). We all agree that, as RB put it ‘imitation did not just happen’ but arose because of relevant selection pressures.

I’m sure others will describe the many areas of agreement better than I can. I would prefer to note some points of disagreement or openness and the shifts that took place as we discussed the wide range of differing ideas and research methods.

Dan Sperber

These are Dan Sperber's thoughts on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BlackmoreBoydClaidièreGodfrey-SmithHenrichMorinRichersonSterelny

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Let me fist express my heartfelt gratitude to Dan for this great initiative, and to Louis Godbout and to the SFI for making it possible. It has been a wonderful workshop of serious, demanding, insightful, informal, friendly discussion of a kind and quality rarely experienced.

I would like to thank all the participants for their contributions, which have all been inspiring, and also for their willingness to entertain and help develop the idea of cultural attraction that has been a long time in the making, but that is still very much in a work-in-progress stage. I am particularly grateful to Pete and Rob and Joe, who have done so much more for so long to develop our understanding of cultural evolution and our capacity to model it. Given the sheer qualitative and quantitative importance of their work in the area and their unique level of expertise, they could have been, if not dismissive, at least much more severe in their reaction to the work of the attraction gang. Instead of which, they have been attentive, constructive and really very helpful. This is what I had hoped for, but was not sure of getting. Rob’s own post-meeting written comments shows how, given their expertise, they are in a position to improve on our suggestions and to make the very idea of attraction a better articulated one, especially but not uniquely on the modelling side, and I hope they will.

Peter Godfrey-Smith

This is Peter Godfrey-Smith's summary of the workshop on cultural evolution convened by Dan Dennett in Santa Fe in 2014. Dennett's introduction is here. Click to see other summaries by Blackmore, Boyd, Claidière, Henrich, Morin, Richerson, Sperber, Sterelny.

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I think that a lot of progress was made on clarifying disagreements, even where the disagreements themselves remain genuine. Many of the remaining disagreements are empirical. It's progress when an initially cloudy situation to gives way to a sharper and more definite set of empirical uncertainties.

Micro, Meso, Macro. To set things up I'll make explicit some distinctions between levels of description – between coarser and finer grained perspectives on a cultural system.
Micro-level: I take this to involve individual psychology, person-to-person social interaction, and the making of artifacts by individuals.
Meso-level: Coarser-grained facts about a single culture or population. The spread of a new bow design or a new taboo would be examples.
Macro-level: Cultural phylogenesis and related events. A whole culture might split into two or go extinct.

Peter Richerson

These are Pete Richerson's thoughts on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BlackmoreBoydClaidièreGodfrey-SmithHenrichMorinSperberSterelny. 

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I do think that the disagreements among the various “schools” of cultural evolution represented at the meeting are relatively modest. I’ll first outline areas where I think disagreements are minimal and then raise some points where important issues may be outstanding.

Areas of broad agreement (taking it for granted that people will always disagree in detail)

1. Importance of cognitive processes. Dan S, Olivier, and Nico especially stress the myriad ways in which culture depends upon cognitive processes and in which cultural evolution is affected by such processes. They rightly stress that Rob, Joe and I have used simple models, as one necessarily must, to study the dynamics of cultural evolution. To my way of thinking, “theory” in fields like the evolutionary sciences consists of a toolkit of models, each itself fairly simple. We get at complex phenomena substantially by the piece-wise construction of families of models making different simplifying assumptions relevant to the specific scientific question at hand. Having models that represent cognitive processes more faithfully, perhaps by simplifying the population dynamic processes that Rob and I originally concentrated on, is work well worth doing. Joe has branched out in that direction. Rob and his students have a Bayesian learning model unifies the individual and social learning inference process. Many studies of social learning in humans and animals provide a lot of data on the one-generation-to-the next time scale that one might use to test such models. For example, I think that Olivier’s flop problem is quite real and is worthy of formalizing.

Nicolas Claidière

These are Nicolas Claidière's thoughts on the workshop on cultural evolution convened by Dan Dennett in Santa Fe in May 2014. Dennett's introduction is here. Click to see other summaries by BlackmoreBoydGodfrey-SmithHenrichMorinRichersonSperberSterelny. 
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(Clarification: I use disagreement in the sense of interesting topic that could be discussed/ researched further and questions in the sense of more precise ideas that could help sort out disagreements.)

Interrogation: It just dawned on me that we could have discussed a, maybe important, academic matter: that of our presentation to other academics. When talking about our respective work we often refer to alternative theories (e.g. dual-inheritance, attraction, memetic, etc) which I think gives the wrong impression. Given the amount of agreement that we have seen during this meeting I think it would be more productive to present ourselves as having a common goal with diverging interests rather than competing views on the same phenomena. A first simple way of achieving this is would be to not present our respective work in terms of alternative theories but just refer to actual articles (so instead of saying ‘memetic theory assumes that’, I am now going to say ‘Dan Dennett told me that’). Another, more complicated way would be to agree on a common denomination (I am really bad at the naming business so I won’t even try to make a suggestion here) that could for instance figure in the title of the report Dan will prepare and that we might want to publish (I personally would like that). Anyway, I thought I would throw this out because I would like to hear what you think about that.

Perspectives on Cultural Evolution, by Daniel C. Dennett

These are Daniel Dennett's introductory remarks on the workshop on cultural evolution he conveyed in Santa Fe in May 2014. 
Click to see the summaries and comments by Blackmore, Boyd, Claidière, Godfrey‑Smith, Henrich, Morin, Richerson, Sperber, Sterelny.


Perspectives on Cultural Evolution 


(Footnotes contain comments by Richerson and Sperber.)

Ever since Darwin’s Descent of Man (1871), the idea of adopting an evolutionary perspective on human culture has seemed to many to be a natural move,  obviously worth trying—and to many others to be a dangerous, “nihilistic,” “reductionistic”, “scientistic,” assault on everything we hold dear.   Work on cultural evolution has been making good progress in recent years, but has been hindered by distortions, some perhaps deliberate, but others are misunderstandings that naturally arise between slightly different traditions.  I formed this working party to try to find common ground and resolve differences among some of the leading theorists and experimentalists.  The ten participants included the trio of Boyd, Henrich and Richerson (BRH), a French trio of Sperber, Claidière and Morin (SCM), the memeticists Blackmore and myself, and two philosophers of biology who have been particularly engaged with issues of cultural evolution, Peter Godfrey Smith and Kim Sterelny.  Several other leading figures were invited but could not participate for various reasons.   

Big Gods Book Club #6: Concluding Thoughts

(This post concludes our "book club" webinar discussing Ara Norenzayan's latest book with its author. This précis introduced the discussion.)

In what follows I’ll make some general concluding comments, and also address four remaining posts by Nicolas, Olivier and Martin, who raise similar points, and Claire, who is offering ideas about how karmic religions work.

I want to say again that I wrote this book as the most up-to-date synthesis that made sense to me. Theories are always work in progress, particularly theories that are about something we know so little about. As David Wilson once wrote, we know more about the evolution of one species of fish – the guppy, then the evolution of religion. Scientifically speaking, we know pathetically little about the karmic religions in particular. Hinduism, Buddhism, and Jainism combined, that’s way over a billion non-WEIRD human beings! So I am glad that Claire is starting much needed research in this area.

I started working on this topic with Scott Atran looking at religion as a cognitive byproduct. Over the years, I came to the conclusion that the byproduct account, as foundational as it is, takes us only so far. I began to change my mind. I became convinced that to explain a wider range of facts about what we think of as “religion,” we need to build on and broaden the cognitive byproduct account. We need to combine insights from this perspective with another dynamically growing field  -- cultural evolution. This book is the product of this ongoing intellectual journey. I wouldn’t be surprised if I change my mind again as more facts and insights pour in.

'Big Gods' book club #5: Remarks on the two puzzles

I like Ara’s way of studying scientific problems very much, weaving together various disciplines from evolutionary modelling to experimental psychology or social anthropology, and I also like the way he tries to solve the questions he raises. However, I am less enthusiastic about the puzzles he chooses to focus on, i.e.:

1. ‘How did human societies scale up from comparatively small, mobile groups of foragers to massively large societies, even though anonymity is the enemy of cooperation?’

2. ‘And how did organized religions with Big Gods – the great polytheistic and monotheistic faiths – culturally spread to colonize most minds in the world?’

Regarding question 1, people working in social sciences, in economics, in anthropology or in sociology, might not feel that this is a puzzle and, on the contrary, might contend that they have already put forward a bunch of answers, most of them along the lines of building efficient institutions, relying on efficient monitoring, reputation management, or low-cost punishment (North, 1990, Ostrom, 1990, Hechter 1992, Acemoglu, Johnson, & Robinson, 2002; Greif, 1998). These solutions show that you can achieve cooperation without trust and altruism as long as you find the correct way to incentivize and monitor cooperative behaviors. In this perspective, social scientists don’t feel they need religion to explain cooperation, neither in contemporary Sweden, nor in medieval China, nor in ancient Rome.

As for question 2, Ara emphasizes that we need to explain why there are so few religions today, in contrast to the great number of primitive religions. But is it really a puzzle?

'Big Gods' book club #4: Alternative explanations?

Unfortunately, I had to read this book more quickly than it would deserve; still, it is an engaging, up-to-date and pleasant synthesis of works from different disciplinary fields. There are, however, several alternative hypotheses that the book does not confront. Some seem plausible to me, some less so. I am curious to know how they could be addressed in the framework of the book. I briefly present three of them; each one was inspired by one of the 'Eight Principles of Big Gods' presented in the book.

Principle 3: Hell is stronger than heaven (when it comes to predicting others' behavior)

Preference for interactions with believers may not be caused by atheists being considered as free-riders. Atheism in others may give rise to other kinds of predictions and prejudices, beyond the assumption that atheists are free-riders. Not submitting to religious beliefs could authorize some of the following inferences:

'Big Gods' book club #3 : Testing more specific hypotheses and going beyond correlations in the origins and evolution of religious beliefs

(This week, cognitionandculture.net is hosting a "book club" webinar discussing Ara Norenzayan's latest book with its author. This précis introduced the discussion.)

In his insightful précis, Ara Norenzayan proposes a model of how religions with “Big Gods” have become almost universal. According to this model, the human cognitive architecture coupled with fitness enhancing cultural practices and beliefs allowed human societies to increase in size and become more cooperative than they would have been without them. Religions with big gods, according to this view, are the products of this interplay between our cognitive architecture and cultural innovations. One problem faced by big societies is that the bigger they are the more anonymous interactions between individuals are. And the more anonymous these societies are, the more prone they are to carrying unpunished selfish individuals which in turn increase the probability of these societies to collapse. One solution to this problem is the existence of policing mechanisms.

'Big Gods' book club #2: Analytic atheism and the puzzle of apologetic

(This week, cognitionandculture.net is hosting a "book club" webinar discussing Ara Norenzayan's latest book with its author. This précis introduced the discussion.)

Norenzayan’s Big Gods presents an elegant account of how belief in super-knowing, powerful and morally concerned gods emerged as a result of normal individual cognitive processes and cultural selection. Any comprehensive account for the success of religion should be able to explain the wide distribution of atheism, which is currently the fourth most popular ‘religious’ outlook. Norenzayan proposes four roads to atheism: atheism caused by deficits in desire-belief reasoning, indifference towards religion, lack of exposure to public displays of religious acts, and analytic atheism.

Here, I will focus on analytic atheism and present Norenzayan with a challenge for his suggestion that analytic thinking counters religious belief. If analytic thinking decreases religious belief, how can we explain the persistence and cultural success of philosophical theology, which consists of analytic reasoning about God/the gods?

'Big Gods' book club #1 — Skeptical thoughts

(This week, cognitionandculture.net is hosting a "book club" webinar discussing Ara Norenzayan's latest book with its author. This précis introduced the discussion.)

I have to confess that I may be misunderstanding the point that Ara Norenzyan's makes in this thought-provoking précis. When Ara talks about 'Big Gods' watching us from the sky, I immediately think of the moralizing religions that emerged around the time that people since Karl Jaspers have called the 'Axial Age', in the first millennium BCE. Whether the concept of an axial age makes sense at all is debated, but the basic idea — that moralizing religions with a supreme Being embodying moral values are a modern phenomenon — is sensible to me.

Ara is probably thinking about something slightly different. His 'Big Gods', he suggests, had something to do with the rise of civilization in the Neolithic period, several millennia before anything like the 'Axial Age' (however we define it) occurred.

Whatever the Neolithic equivalent of Big Gods could have been, I am not sure they did their job as well as Ara implies. My (admittedly unschooled) view of the first great civilizations is of a world built by raids, wars, and the all-important institution of slavery. This is certainly not the whole story — raiding, warring and slaving are cooperative ventures, after all, and might require a modicum of coordination between distant acquaintances, if not strangers. Yet, rightly or wrongly, this makes me suspicious of a rosy-colored picture of the early ages of civilization.

A précis of 'Big Gods: How Religion Transformed Cooperation and Conflict'

(This week, cognitionandculture.net is hosting a "book club" webinar discussing Ara Norenzayan's latest book with its author. This précis introduces the discussion.) big gods

On a hilltop in what is now Southeastern Turkey rests the world’s oldest temple of worship. With its massive, T-shaped stone pillars carved with images of animals and arranged in a set of rings, Göbekli Tepe is challenging long-held conceptions about the origins of civilization. While archeologists are unearthing clues and debating their meaning, there remain many unanswered questions. Yet, the significance if this site continues to grow.

No evidence of agriculture has been found, which may be explained by the fact that the site dates back about 11,500 years. The monumental architecture of Göbekli is old enough to have been built by hunting and foraging people, but massive enough to require the participation of many hundreds, possibly thousands of them, without the technological advantages of settled agriculture. True, foraging groups, despite their relatively small sizes, are known to vary in scope, densities, and degree of mobility. But what sets Göbekli apart is its scale and religious grandeur, despite its ancient origins. It gives us tantalizing clues that worshippers from the wider region periodically congregated there to worship and perform rituals. It may therefore hold clues to two of the deepest puzzles of human civilization. How did human societies scale up from comparatively small, mobile groups of foragers to massively large societies, even though anonymity is the enemy of cooperation? And how did organized religions with Big Gods – the great polytheistic and monotheistic faiths – culturally spread to colonize most minds in the world?

Robin Dunbar vs. Pop Dunbar

This post is part of a Webinar, Debating Dunbar's Number.

Part 1Part 2Part 3

While reading the stimulating critique of Robin Dunbar's social brain hypothesis recently published by Jan de Ruiter and his colleagues, my first reaction was: "Straw man!". On second thoughts, it wasn't fair. The author that Jan de Ruiter and his colleagues criticize is sometimes a caricature of Robin Dunbar. Yet he resembles another important author — let us call him Pop Dunbar. Pop Dunbar stands for many things that have been said in Dunbar's name by the popular press. Robin Dunbar has often distanced himself from Pop Dunbar's ideas, but many of us got interested in his ideas through the Pop version. Pop Dunbar’s ideas are not trivially wrong, and, as Jan de Ruiter and colleagues note, his influence is enormous. For some people, Pop Dunbar holds the truth on what friendship should be.

So, in this post, I thought I would follow in the wake of Jan de Ruiter and colleagues, and explain what I find wrong with some ideas that I attribute to Pop Dunbar. While writing this text I realized that I often (though not always) seemed to find the real Dunbar on my side.

Pop Dunbar's theory says that, in primates, brain size forbids any individual from having more than a certain amount of friends. Because of this limit, primate societies, including ours, cannot go beyond a certain size. This pop theory is simple, powerful, fascinating — and probably inaccurate.

Are we sure we can groom beyond Dunbar's number?

This post is part of a Webinar, Debating Dunbar's Number.

Part 1Part 2Part 3

When I heard about Kanai et al.'s paper [1] announcing a correlation between grey matter density in several brain areas and online social network size, I immediately updated my Facebook status, and touted the size of my brain in the eyes of my 500 friends. Well, Kanai et al.’s findings were not at all about its size; they were limited to very specific parts of it. Yet I must admit that I maliciously took advantage of the ignorance of some of my mates. Their reactions to my childish post were various: some of them made fun of me, some pretended to be impressed. There was inevitably a bunch of them to criticize the findings as well as my own 'interpretation' of the results. Eventually, there were also a significant number of people who threatened my concept of 'friendship'. After all, how could I have 500 real friends when, as everybody knows, one can only maintain about 150 social bonds? Even Britney Spears knows that. Rumor has it that she chose to join the social network Path where the number of interactants is limited to 150. Why 150? Path’s cofounder Dave Morin justifies this limit by quoting Robin Dunbar's work on the social brain hypothesis: this is our 'social ceiling'. One cannot maintain approximatively more than 150 trusted relationships.

Here is the rationale behind this claim.

Subcategories

  • PedagogyWeek

    In November 2010, an informal on-line workshop gathered psychologists and philosophers, to discuss the implications of a new theory of human communication and cultural transmission. Participants were György Gergely, Olivier Morin, Dan Sperber, Marion Vorms and Davie Yoon.

    Article Count:
    6
  • Decision-making for a social world

    The International Cognition and Culture Institute (Institut Jean Nicod and LSE) and the Philosophy, Politics and Economics Program at the University of Pennsylvania organize a virtual seminar Decision Making for a Social World. The aim of this seminar is to bring together threads of research in decision making and related areas of psychology that show how deeply our decisions are influenced by our social context. Some of this research even takes the stronger stance that some of the mechanisms that are typically thought of as being within the purview of individual cognition actually have a social function. It will begin in February 2011. Every two weeks a new paper will be posted and a moderated discussion will take place online among invited discussants and the public one the one hand, and the author on the other hand. Here are some of the themes that will be explored: Group decision making. This is the primary case of direct influence of the social context. Groups can allow people to solve more complex problems but they can also amplify their biases. Through which mechanisms is their influence exerted? Accountability. The social context often exerts an influence on our decisions because we have-or at least we think we will have-to publicly justify our decisions. Trust and advice taking. Many of our decisions have been influenced by the advice given by other people. Are we influenced by advice too much or too little? How do we calibrate the weight put on the advice as a function of who is offering it? Pragmatics. Most decision making tasks use verbal material, yet they frequently ignore that such material will often lead to pragmatic implications that can influence participants' answers. Evolution. Many scholars in the field of human evolution contend that social factors were the primary pressure in our evolution, yet the field of decision making has failed to draw all the implications from this suggestion. These are only examples as many areas in decision making show that the social context exerts a huge impact on our decisions, from the study of norms to that of self-control. We look forward to the opening of the conference and the discussions that will ensue! Hugo Mercier

    Article Count:
    15
  • Dunbar's number
    Article Count:
    3
  • 'Big Gods' book club
    Article Count:
    7
  • SFI Cultural Evolution Workshop
    Article Count:
    11

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