VU University, Amsterdam

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Research and Research Instruments

Trust and Human Cooperation

People aggress and retaliate, people care and help, people cooperate and compete.  Are we naturally good, naturally bad, neither or both?   What are the functions of fairness, empathy, generosity, forgiveness, and gratitude?  And what are the functions of competition, retaliation, and even hate?  Many of these specifc issues are examined under the heading of Trust and Human Cooperation.

Scientifically, trust and human cooperation constitute one of the most comprehensive and challenging topics one can address. Most inside-the-head phenomena (such as trust) or deeply rooted biological capacities (such as empathy) help us "determine" how we should approach another person.  And most inside-the-head phenomena help us make sense of the social world around us. And societally, if we really understand trust and human cooperation, then we are much better equipped at understanding several key questions - how can we improve unselfish behavior in relationships and small groups, how can we promote energy-friendly actions, how can we optimize coordination in traffic and elsewhere, how can we improve interactions among ethnically diverse groups, and even how can we prevent or resolve conflict between groups and broad forms of international conflict.

My research focuses on several topics that center on trust and human cooperation, such as fairness, forgiveness, generosity, beliefs about human nature, competition, retaliation, and misunderstanding.  We often study trust and human cooperation within the framework of social dilemmas - or conflicts between self-interest and collective interests.  The recent literature on the psychology of social dilemmas has been recently summarized in a textbook on social dilemmas.  We also have developed numerous paradigms that allows one to study trust and human cooperation, including decomposed games (Van Lange, Otten, De Bruin, & Joireman, 1997), the coin task (Van Lange et al., 2002), the parcel delivery paradigm (Klapwijk & Van Lange, 2009), the dice-rolling task (Vuolevi & Van Lange, 2010), and the somi task to assess social mindfulness (Van Doesum, Van Lange, & Van Lange, 2013).  Based on a strong interest in trust and human cooperation, and years of research we have also developed tentative - or less tentative - conclusions about the trusting and cooperative nature of humankind, as well as the ways in which trust and human cooperation can be promoted.  Some of these conclusions or beliefs are summarized below.

Self-interest is overestimated inside and outside of science

My original interests focused on extensions of the assumption of rational self-interest, thereby addressing the concept of social value orientation. In particular, my earlier research illuminated the theoretical and predictive value of prosocial, individualistic, and competitive orientation in determining motivation, cognition, and behavior in social interaction situations, social development contexts, political contexts, and ongoing relationships (see Van Lange & Kuhlman, 1994; Van Lange, Otten et al., 1997).

Generosity outperforms reciprocity (or stinginess) in most situations

Rather than giving an eye for an eye and engaging in social book-keeping, my research seeks to delineate the circumstances under which acts of sacrifice, generosity, and forgiveness provide benefits through interaction - an issue strongly relevant to the evolution of cooperation. For example, my research (with several colleagues) has provided evidence in support of the functionality of sacrifice in ongoing relationships, generosity in situations in which misunderstands are bound to happen, and forgiveness in committed relationships (see Van Lange et al., 1997; van Lange, Ouwerkerk, & Tazelaar, 2002; Karremans et al., 2003). Among the various issues, I seek to extend this line of research by examining the functionality of honesty (i.e., genuine and open communication), gratitude, and clarity, especially in situations in which misunderstandings are bound to happen.


It is uncommon to link culture to climate.  Yet we see many mundane differences in what people wear, what they eat, and how they structure the day in warmer versus colder climates.  Beyond these differences, we also see that societies differ strongly in terms of time orientation.   In countries closer to the equator, time mattters less.  Punctuality matters less.  In Trinidad, located at the equator, there is a saying:  "Any time is Trinidad time."  Incountries farther away from the equator, "time is money"  and planning becomes one of the strongest priorities.  Also, we see that aggression is uneqaully distributed around the world.  Setting exceptions aside, aggression and violence is higher in warmer climates than in colder climates.  Along with Bela Rinderu and Brad Bushman, we have developed a model of CLimate, Aggression, and Self-contol in Humans (CLASH), which appeared in Behavioral and Brain Sciences.  We also wrote a response (and Figure) to 28 commentaries written by 80 authors

"Bridging" and theorizing in (social) psychology is essential for genuine scientific progress

My activities also center on examining "bridges" between social psychology and other fields of psychology or disciplines - such as neurosciences, other fields of psychology, and economics (see Van Lange, 2006). Also, I intend to examine the utility of social psychological theories by examining not only standards such as Truth, Abstraction, and Progress, but also Applicability to Society.  Recently, Icompleted an co-edited Handbook of Theories of Social Psycholog (see Van Lange, Kruglanski, & Higgins, 2012), in which numerous theories are described, typically by the person(s) who advanced and developedthe theory.  They describe not just the theory itself, but also the personal story behind the theory (how and why they developed it) and many authors devote careful attention to the applicability of the theory.  I truly enjoyed editing this volume, and I am working on papers that address topics that are closely linked to ideals for theorizing in (social) psychology.

Nothing is as basic to social life as trust and human cooperation

I find topics such as social comparison, self-control, and social exclusion truly fascinating.  From an interdependence perspective, they are basic to social interaction, and as such, I see them as strongly connected to the study of trust and human cooperation.  Social comparison in many ways might trigger competition, both the aversive form (not getting less than others) and the appetitive form (getting more than others); self-control is about the delay of gratification, which in social settings often imply taking the "longer-time perspective" by giving others the benefit of the doubt, communicating trust, and signaling boundaries; and social exclusion often operate at the level of collective, in that subjectively or objectively, exclusion is often believed to make sense at the level of the group.  Some of my older work on the Muhammad Ali effect (Van Lange, 1991; Van Lange & Sedikides, 1998) reflects a social comparison ("I am better than others, but not necessarily more competent than others) that is essential to social interaction.  The SLAM effect (Stressing Limiting Aspects in Others' Manuscripts, Van Lange, 1999) is essential to social exclusion, as the more recent finding that reminders of significant others help us regulate and cope with threats of social exclusion (Karremans et al.  2011).  I also believe that trust and human cooperation are basic to understanding the development of political beliefs and ideology (for some evidence, Van Lange, Bekkers, et al., 2012), and that social interaction experiences can also importantly shape differences in trust and human cooperation.  Over the past years, although nature and nurture do not exclude each other,  I have come to believe that trust is more a matter of culture (cultural evolution) and sometimes subtle influences rather than strong genetic predispositions - for evidence, see Balliet & Van Lange, 2013; Van Lange et al.,  2014 and 2015.


Measuring social value orientation

          Triple-Dominance Measure of Social Values [pdf] [doc]

Measuring cooperation in the gradual social dilemma task

           SeeVan Lange et al., 2002;  see Klapwijk &Van Lange, 2009)


Measuring Trust in Others (and Beliefs about Others' Trust in Self)

           see Van Lange, Vinkhuyzen, & Posthuma(2014)    pdf

          see also article


Measuring beliefs and cooperation

  • The coin incomplete information task (used in Vuolevi & Van Lange, 2012), [pdf]
  • Vuolevi, J. H. K., & Van Lange, P. A. M. (2012).  Boundaries of reciprocity: Incompleteness of information undermines cooperation. Acta Psychologica, 141, 67-72.  [pdf]


  • Bridging Social Psychology
  • Cooperation and competition
  • Forgiveness
  • Generosity
  • Impression formation
  • Interdependence
  • Morality
  • Noise and Misunderstanding
  • Social dilemma
  • Social interaction
  • Social value orientation,