Toddlers have an intuitive sense of justice as they prefer to treat others the way they expect themselves to be treated, a research said.
But unlike adults, they are not much interested in doling out punishment. They would rather console a victim, the study showed.
For instance, young children prefer to return lost items to their rightful owners.
"The chief implication is that a concern for others – empathy, for example – is a core component of a sense of justice," said Keith Jensen of University of Manchester.
"This sense of justice based on harm to victims is likely to be central to human prosociality as well as punishment, both of which form the basis of uniquely human cooperation."
Both three- and five-year-old children are just as likely to respond to the needs of another individual – even when that individual is a puppet – as they are to their own.
In human society, cooperation is often encouraged by punishing free-riders. However, earlier studies have shown that chimpanzees do not punish cheaters unless they themselves have been harmed directly.
To find out what motivates a sense of justice in young children, researchers gave three- and five-year-olds the opportunity to take items away from a puppet that had "taken" them from another.
Those children were as likely to intervene on behalf of a puppet "victim" as they were for themselves. When given a range of options, three-year-olds preferred to return an item than to remove it.
"It appears that a sense of justice centred on harm caused to victims emerges early in childhood."
The results appeared in the journal Current Biology.