November 28, 2023

Vacancy for a PhD student (full-time, 4 years) “Effects of economic inequality on cooperation and conflict between groups” at Leiden University ( The Netherlands) – Deadline: December 18, 2023

Link to the call: PhD student (full-time, 4 years) “Effects of economic inequality on cooperation and conflict between – Leiden University (

Article applying knowledge about social dilemmas to the crises of climate change, COVID-19, and misinformation

October 15, 2021

D. Michael Kuhlman (“Mike”)

It is with great sadness that we share the news that Mike Kuhlman passed away recently, due to the consequences of cancer at the age of 78. He is survived byhis two sons, Andy and Jamie; daughter, Jessica; and four grandchildren. His beloved wife, Marilyn, passed away in 2007.

Education and career

Following his undergraduate education at the University of Missouri – Columbia, Mike earned his doctoral degree in psychology at the University of California, Santa Barbara. Soon after, he started his career in 1970 at the University of Delaware where he retired in January 2019.

Some examples of his major contributions

Mike’s scientific ideas and research were sophisticated in every sense of the word. His work on social value orientation was inspired by his supervisors Chuck McClintock and David Messick, and Mike in turn inspired many people to develop theories and ideas about Js, Os, and Rs, people who enhance Joint outcomes, Own outcomes, or Relative Advantage over others. Mike was truly passionate of these differences in social value orientation. While he was one of the greatest experts of the world on social value orientation, he always wanted to hear what others had to say. Mike also conducted beautiful experiments, designed to provide very clean tests of clear and novel hypotheses, and knew a tremendous amount about a range of statistical techniques, which he generously shared with his graduate students. His scientific articles with Marshello and Wimberley are true classics in social psychology. He was also an example of a social and personality psychologist, and his work with various colleagues at the University of Delaware were often focused on individual differences – a topic that he also taught for many years – with an emphasis on broad dimensions of personality. He was also a scientist with a strong international orientation, working together with scientists in especially Japan, Poland, and The Netherlands. With all these collaborations, he developed warm friendships, which were recently supported by exchanges through email, zoom, and Whatsapp.

Inspired by ideas, warmth, and humor
Mike was also a gifted speaker. Once he took the floor, he was ready and showed a unique combination of passion for ideas, commitment to logic, and appreciation for humor. This combination of favorable qualities was very inspirational, but the ideas, along with the passion with which he shared them, were the ones that stood out the most. It was common for a sizable group of people to still discuss ideas over dinner and late drinks. These were also the moments where everybody truly enjoyed having Mike around. His warmth and generosity were contagious. Scientists, young and more senior alike, felt completely comfortable with Mike. It was striking that rather than lecturing, Mike would be equally, if not more likely to listen to young students. He was interested in ideas, and often deeply interested in the person behind these ideas. And he enjoyed good stories. Although he was a top story teller, he was patient and generous to always give the other person the floor first. As part of his warmth and generosity, Mike was exceptional in his sense of humor. It was strongly interconnected with his view of life, and perhaps his slight dislike of anything that had some smell of expressing self-importance. Part of his humor also centered on language, including foreign language. Many Dutch people know of Mike’s inclination to share Dutch expressions, or his unique way of saying goodbye: “I guess this is me leaving.”

We will remember Mike not only as a truly inspiring and creative scientist with a strong drive for ideas, but also as a person with an exceptional sense of humor and skill at story-telling. He was so warm and generous that he always allowed others to share their ideas, jokes, and stories first. His interpersonal life was filled with giving and sharing, in that order.

Mike will be deeply missed.

Paul van Lange, Jeff Joireman, Gregory Shelley, and Adam Stivers

April 27, 2021

David Messick

It is with great sadness that we share the news that Dave Messick passed away yesterday. 

He is survived by his wife Judy and two sons.  Dave’s passing is an immense loss to our field, and especially to the social dilemmas community to which he was a founding father.  We remember him as an outstanding scientist, as a splendid mentor, and above all, as a wonderful friend, and we will miss him dearly.

We will celebrate Dave’s life and career in our 2022 ICSD meeting.

March 4, 2021

International Conference on Social Dilemmas postponed to 2022

We would have loved to welcome you in Copenhagen this summer, but unfortunately, there will be no ICSD in 2021. In conjunction with the ICSD steering committee we have decided to reschedule the conference for 2022.

We initially hoped that it would be possible to hold an in-person or hybrid conference this summer. At the moment, however, it seems very unlikely that we could have a conference without severe limitations. Vaccination in many European countries runs slowly, and it is not clear whether all participants would be able to get vaccinated before the conference. Relatedly, it is unlikely that all restrictions on travel and events will be lifted until July. Even if people can get vaccinated and restrictions will be lifted, all of this would likely be decided only very shortly before the conference, leaving many participants in uncertainty until early summer.

Cancelling this year’s conference was a difficult decision for us. For those of you who submitted an abstract or already made plans to attend, we apologise for the inconvenience this causes you.

The exact date for next year’s conference will be determined after the summer. We will be in touch when the date has been set.

We are looking forward to welcoming you in Copenhagen in 2022.


Robert Böhm, Simon Columbus, & Ingo Zettler

Organising Committee 19th International Conference on Social Dilemmas

Call for submissions for the 19th International Conference on Social Dilemmas (2021)


We invite submissions for the International Conference on Social Dilemmas (ICSD), which will be held on July 20-23, 2021, in Copenhagen/Denmark.

Confirmed keynote speakers: Cornelia BetschAstrid Dannenberg and Andreas Diekmann

Conference website with further information:

Submissions: Abstract submissions will be accepted via the conference website until February 1, 2021. Submissions will be evaluated in a double-blind procedure by independent referees.

We are planning to have a classic ‘offline’ conference. Depending on the COVID-19 situation and potential restrictions around travel, we will also offer online participation in a hybrid format. Hence, we invite everyone who is interested in participating to submit an abstract (a final decision about the format will be made in spring 2021, before the registration period).

We are excited to host ICSD 2021 in Copenhagen and hope to welcome many of you!

The ICSD 2021 local organizing team:

Robert Böhm

Simon Columbus

Ingo Zettler


Call for Papers for special issue in Games: Advances in Research on Social Dilemmas

Guest editors: Vincent Buskens, Rense Corten, Wojtek Przepiorka and Werner Raub (Utrecht University)

Abstract: Research on social dilemmas is a topic of the social sciences, including economics, sociology, political science, and social psychology, to name only a few. This Special Issue is explicitly open to contributions from different social science disciplines as well as interdisciplinary work. Submissions based on formal game-theoretic modeling as well as informal but sufficiently rigorous “game-theory-inspired reasoning”, including, for example agent-based modeling, are welcome. We are specifically inviting submissions that address social dilemma problems in new research domains and fields such as incentive problems in science as a social system and studies on exchange involving illegal transactions on online platforms in the dark net. With respect to methods, submissions employing experimental designs (lab, online, and/or field) are welcome, as are studies with quasi-experimental designs using observational data from traditional (survey) and new sources (online), and meta-analyses. Papers using neuroscience methods are likewise welcome. We will also be happy to consider papers of a more methodological nature. This could be papers that combine complementary methodologies and designs to address the same research questions or test similar hypotheses. Papers that focus on linking micro and macro levels of analysis are also welcome. 

Keywords: social dilemmas; game-theoretic models; agent-based models; applications in new research; domains and fields; experimental designs; observational designs; neuroscience methods; complementary methodologies and designs.

Review article applying knowledge about social dilemmas to climate change (open access)


Huckelba, A. L., & van Lange, P. A. M. (2020). The silent killer: Consequences of climate change and how to survive past the year 2050. Sustainability12(9).

Article paying tribute to Anatol Rapoport (open access)

Tit for Tat and Beyond_ The Legendary Work of Anatol Rapoport_1

Kopelman, S. (2020). Tit for Tat and beyond: The legendary work of Anatol Rapoport. Negotiation and Conflict Management Research (NCMR), 13(1), 60-84.

18th International Conference on Social Dilemmas (2019)

The 18th International Conference on Social Dilemmas was held in Sedona (USA) in June 2019. The primary organizers were Tamar Kugler, Poonam Arora and Ann Rumble.


For more information about the program of this conference, see here.

For slides of presentations given at this conference, see here.

May 16, 2018

Toshio Yamagishi

It is with great sadness that we share the news that Toshio Yamagishi passed away last week, due to illness at the age of 70.  He is survived by his wife, Midori Yamagishi.
Education and career
Toshio Yamagishi received his bachelor’s and master’s degrees from Hitotsubashi University in sociology, and his doctoral degree in sociology from the University of Washington in 1981. Soon after, he started his teaching career at Hokkaido University, then moved to the University of Washington in 1985, and back in Japan at Hokkaido University in 1988. After retirement in 2012 from Hokkaido University, he moved to the Brain Science Institute at Tamagawa University, then to the Center for Research in Evolutionary Cognitive Sciences at the University of Tokyo, and finally to the current position at Hitotsubashi ICS.
Some examples of his major contributions
Toshio’s research has made landmark contributions to numerous topics. His early-career research on elementary and instrumental cooperation has been very influential, especially in the last 15 years or so when his insights were part of theorizing and research on reward and punishment in social dilemmas. His work on trust has always been strong in theory and research, and his ideas have become central to cross-national research on trust, including great attention to the differences between Japan and the United States. After his work on heuristics in social dilemmas, with an emphasis on reciprocity or exchange as a heuristic, he extended this work to make a novel theoretical and empirical contribution to intergroup cooperation (bounded generalized reciprocity). Throughout his career, Toshio bridged several disciplines, including sociology, economics, psychology, biology, and more recently, neuroscience.
Inspired by ideas and generosity
Most people probably know that Toshio’s research was always rich in terms of theory. He was inspiring and a wonderful mentor to numerous PhD students, who delivered fantastic presentations at conferences of social dilemmas. Toshio was also inspiring to many colleagues around the world: junior and senior, among economists, psychologists, and sociologists. He would invite many of these colleagues to Sapporo or Tokyo, and was always an incredibly generous host, not only in offering excellent food and accommodations, but also by being an inspirational colleague who was always ready and willing to discuss ideas for hours. Research meetings could easily go on for 12 hours or longer.  Every now and then he would open his laptop and test these ideas on the spot. As a self-described “craftsman” in the art of experimental design, Toshio strived towards perfection in designing optimal studies to test his ideas. And anyone who was lucky enough to work next to him, quickly realized the level of detail he would approach thinking about his experiments. Indeed, he was a true craftsman, and an inspiration for us all.
We will remember Toshio not only as a truly amazing and inspiring scientist, but also as extremely generous and warm person who wanted to exchange, but above all, to give and share. Toshio will be deeply missed.
Daniel Balliet and Paul van Lange

New book on Social Dilemmas, Institutions, and the Evolution of Cooperation


For more info on this book, see this website.

New book in Oxford Series in Human Cooperation

Trust in Social Dilemmas, by Paul A.M. Van Lange, Bettina Rockenbach, and Toshio Yamagishi (Eds)

One of the key scientific challenges is the puzzle of human cooperation. Why do people cooperate with one another? What causes individuals to lend a helping hand to a stranger, even if it comes at a major cost to their own well-being? Why do people severely punish those who violate social norms and undermine the collective interest? Edited by Paul A.M. Van Lange, Bettina Rockenbach, and Toshio Yamagishi, Trust in Social Dilemmas carefully considers the role of trust in establishing, promoting, and maintaining overall human cooperation.

By exploring the impact of trust and effective cooperation on relationships, organizations, and communities, Trust in Social Dilemmas draws inspiration from the fact that social dilemmas, defined in terms of conflicts between self-interest and the collective interest, are omnipresent in today’s society. In capturing the breadth and relevance of trust to social dilemmas and human cooperation more generally, this book is structured in three effective parts for readers: the biology and development of trust; the importance of trust for groups and organizations; and how trust factors across the overall health of today’s society.

For a discount on the Oxford University Press Series in Human Cooperation, see:

discount book series on cooperation

17th International Conference on Social Dilemmas (2017)

The 17th International Conference on Social Dilemmas was held on Sicily (Italy) in June 2017. The primary organizers were Daniel Balliet, Nancy Buchan and the Amsterdam Cooperation Lab.

Group picture

For more information about the program of this conference, see here.