According to new research published in the journal PLoS ONE, a study at the University of Washington has determined that some infants have a fundamental sense of fairness as young as 15 months of age.
The study, led by Associate Professor of Psychology Jessica Sommerville, found that the traits of charity and fairness were evident in infants at a much younger age than previously believed.
The study also showed that those infants who had a more defined sense of fairness were more willing to share a favorite toy.
A group of 15-month-old infants was shown two videos.
The first showed people receiving bowls of crackers containing equal amounts, then the same people received bowls with unequal amounts. The second video used the same scenario using glasses of milk.
To determine the response of the infants, researchers measured the level of surprise they showed at what they saw on the videos. Then the same group of infants was observed to see which ones were willing to share a favorite toy with a stranger.
The infants that were most surprised by the unfair food distribution were more willing to share their toys.
The study seems to indicate that individual personality traits such as fairness develop at an early age.