Even three-year-olds have a keen sense of fairness

Donnie Ray Jones, flickr.com, CCBY20
branking62, Pixabay.com, CC0 1.0

Around the age of two, children start to become more social and to verbalize their own structured thoughts and ideas. They are also learning how to hold a conversation. Then, when they are about three years old, they begin to gain insight into the intentions and actions of other children.

Every parent has witnessed a situation like this: Two young children have started to play a game, with an implicit agreement to abide by a certain set of rules. All of a sudden, one of them abandons the game and starts playing with something else. The child left behind responds by complaining, “Hey, that’s not how the game goes!” or “Mom, she’s not playing right!” Even at the age of three, toddlers have a keen sense of fairness, and they make it very clear when they perceive something to be unjust.

Recent research by anthropologist Ulrike Kachel and developmental psychologists Margarita Svetlova and Michael Tomasello has shown that when three-year-olds play together, they are already able to assess their own intentions and obligations and those of their playmates.


In the study, 72 pairs of three-year-olds were asked to play a collaborative game called “feeding the elephant,” with one child acting as the “subject” and the other as the “partner.” The first child is given instructions on how to play the game. The goal is to win a marble to “feed” the elephant, which requires pulling two ropes simultaneously, one on the left and the other on the right. This is possible only through collaboration. After explaining the game to the subject child, the researcher brings the partner child into the room and encourages the children to play the game together.

Three conditions may interrupt the game: (1) The researcher has taught the partner child a different method of feeding the elephant, so the child stops playing the game; (2) the subject child is led to believe that the partner child is unaware of the rules of the game; or (3) the equipment breaks.

“Three-year-olds appear to respond to violations of a commitment in much the same way as adults do, which suggests that they already have a nuanced appreciation of intentionality.”

The subject child reacts differently to each of the three conditions. In the first case, the child protests when the partner child suddenly stops cooperating; in the second case, the child tries to teach the rules of the game to the partner; and in the third case the equipment itself is blamed.

“These are responses one might expect of competent moral agents, individuals who are capable of normative assessments and who treat their counterparts as competent moral agents as well,” the authors of the study explain. Indeed, three-year-olds appear to respond to violations of a commitment in much the same way as adults do, which suggests that they already have a nuanced appreciation of intentionality.

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