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Department of Psychology Social and Economic Psychology

Jörg Gross

Jörg Gross, Prof. Dr.

  • Chair
+41 44 635 72 30
Room number
BIN 3 C.02

Current Research Interests


Humans possess a remarkable capacity to engage in large-scale cooperation. Within groups, we disseminate knowledge, coordinate actions, and establish and sustain public goods from which everyone can benefit. However, cooperation is susceptible to exploitation and presents a social dilemma. When others do not cooperate, the optimal response is often to refrain from cooperating as well. Conversely, if others cooperate, individuals may be tempted to reap the benefits of cooperation without contributing themselves. This research focus aims to understand how groups can overcome this free-rider problem, reaveal mechanisms to maintain cooperation, and explore how group cooperation shapes expectations and trust dynamics among individual members.

Social Norms

Closely intertwined with cooperation are social norms. Broadly defined, norms represent (implicit) expectations shared among individuals, delineating appropriate behavior in various contexts. Cooperation norms are of particular interest, as they often necessitate curbing selfish actions for the creating collective benefits. However, we still lack a comprehensive understanding of how such norms emerge within groups, how they persist, and how they shape behavior, even when not overtly observable by others. Additionally, groups may cultivate 'anti-social' norms that legitimate harm or unethical conduct towards others. A better understanding of the development and behavioral influence of norms would enable us to better predict the conditions under which groups effectively cooperate, compete, or disband.


Cooperation entails investing personal resources (time, money, energy) for the benefit of others. However, humans frequently also allocate substantial resources to cause harm, exploit, or compete with others. In conflict scenarios, resources are wasted and only serve to to assert dominance or outcompete others. Therefore, a pivotal goal is to identify the circumstances under which individuals are inclined to spend time and effort to harm others. Particularly in intergroup contexts, understanding mechanisms that de-escalate conflict and foster intergroup cooperation may help to resolve perpetuating conflict dynamics.

Academic Positions

since 2022 Professor for Social and Economic Psychology
University of Zurich
2016-2022 Assistant Professor
Department of Social, Economic and Organisational Psychology,
Leiden University (Netherlands)
2015-2016 Postdoctoral Research Fellow
Institute of Psychology,
University of Amsterdam (Netherlands)
2011-2015 PhD studies
Department of Economics & Department of Cognitive Neuroscience,
University of Maastricht (Netherlands)
Advisors: Prof. Dr. Arno Riedl (Economics) & Prof. Dr. Rainer Goebel (Psychology)
2005-2010 Study of Psychology
Goethe University Frankfurt (Germany)

Selected Publications

Gross, Meder, De Dreu, Romano, Molenmaker & Hoenig (2023). The evolution of universal cooperation. Science Advances.

Gross, De Dreu & Reddmann (2022). Shadow of conflict: How past conflict influences group cooperation and the use of punishment. Organizational Behavior and Human Decision Processes.

Gross & Vostroknutov (2022). Why do people follow social norms? Current Opinion in Psychology.

Gross et al. (2021). When helping is risky: The behavioral and neurobiological tradeoff of social and risk preferences. Psychological Science.

Gross & Böhm (2020). Voluntary restrictions on self-reliance increase cooperation and mitigate wealth inequality. Proceedings of the National Academy of Sciences.

Gross & De Dreu (2019). Individual solutions to shared problems create a modern tragedy of the commons. Science Advances.

Gross & De Dreu (2019). The rise and fall of cooperation through reputation and group polarization. Nature Communications.