Searching for the developmental origins of fairness

Six experiments addressed two major questions related to the development of infants’ concern for fairness: 1) at what age do infants first show a concern for fairness in terms of how objects should be distributed? and 2) how does group membership influence infants’ expectations about how objects should be distributed? In Experiment 1, 9-month-olds expected an experimenter to divide two items equally, as opposed to unequally, between two individuals. Infants held no particular expectation when the individuals were replaced with inert objects, or when the experimenter simply removed covers in front of the individuals to reveal the items (instead of distributing them). In Experiment 2, these findings were extended to 4-month-olds who also expected an experimenter to divide two items equally between two recipients when they were animate but not when they were inert or when the experimenter removed covers to reveal the items. In Experiment 3, 19-month-olds expected a distributor to divide two items equally between two similar individuals who belonged to a different group. In Experiment 4, 19-month-olds expected a distributor, who belonged to the same group as one of two potential recipients, to favor his ingroup member when he had only two items to divide. Infants found it unexpected when the distributor divided the items equally or when he gave both objects to the outgroup individual. In Experiment 5, the distributor had three toys to divide (instead of two) and 19-month-olds now no longer found it unexpected when the distributor gave one object to each recipient. In Experiment 6, 19-month-olds expected an experimenter who had many new markers to replace the broken marker of her ingroup member but not that of an outgroup individual who also had a broken marker. In combination, these results provide evidence that 1) infants in the first year of life already expect fair allocations and 2) by the second year of life, infants consider ingroup loyalty as well as fairness when reasoning about resource allocations: at 19 months, infants privilege favoring the ingroup over fairness when resources are either scarce or needed by the ingroup to accomplish some tasks