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

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.