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Sunday, February 6, 2022

Trolley Dilemma in Papua. Yali horticulturalists refuse to pull the lever

Sorokowski, P., Marczak, M., Misiak, M. et al. 
Psychon Bull Rev 27, 398–403 (2020).


Although many studies show cultural or ecological variability in moral judgments, cross-cultural responses to the trolley problem (kill one person to save five others) indicate that certain moral principles might be prevalent in human populations. We conducted a study in a traditional, indigenous, non-Western society inhabiting the remote Yalimo valley in Papua, Indonesia. We modified the original trolley dilemma to produce an ecologically valid “falling tree dilemma.” Our experiment showed that the Yali are significantly less willing than Western people to sacrifice one person to save five others in this moral dilemma. The results indicate that utilitarian moral judgments to the trolley dilemma might be less widespread than previously supposed. On the contrary, they are likely to be mediated by sociocultural factors.


Our study showed that Yali participants were significantly less willing than Western participants to sacrifice one person to save five others in the moral dilemma. More specifically, the difference was so large that the odds of pushing the tree were approximately 73% smaller for a Papuan in comparison with Canadians.

Our findings reflect cultural differences between the Western and Yali participants, which are illustrated by the two most common explanations provided by Papuans immediately after the experiment. First, owing to the extremely harsh consequences of causing someone’s death in Yali society, our Papuan participants did not want to expose themselves to any potential trouble and were, therefore, unwilling to take any action in the tree dilemma. The rules of conduct in Yali society mean that a person accused of contributing to someone’s death is killed. However, the whole extended family of the blamed individual, and even their village, are also in danger of death (Koch, 1974). This is because the relatives of the deceased person are obliged to compensate for the wrongdoing by killing the same or a greater number of persons.

Another common explanation was related to religion. The Yali often argued that people should not interfere with the divine decision about someone’s life and death (e.g., “I’m not God, so I can’t make the decision”). Hence, although the reason may suggest an action as appropriate, religion suggests otherwise, with religious believers deciding in favor of the latter (Piazza & Landy, 2013). In turn, more traditional populations may refer to religion more than more secular, modern WEIRD populations.