Do kids outgrow socialism? A fascinating new study, "Fairness and the Development of Inequality Acceptance," [subscription required] published last week in the journal Science by researchers at the Norwegian School of Economics and Business Administration sheds some light on individual moral development. It turns out that as people move from childhood through adolescence to young adulthood they become increasingly meritocratic, that is, they come to believe that people deserve unequal rewards based on their individual achievements.

The Norwegian researchers studied about 500 children beginning in the fifth grade through the 13th grade (ages 11 through 19) as they played modified versions of the dictator game. In the standard dictator game, a sum of money, say $100, is divided up between two players. The dictator decides how much to keep and how much to give the second player, the responder. Interestingly, research shows consistently that most dictators do not keep all the money.

The Norwegian researchers modified the game allowing for a 45-minute production phase in which players could earn points by finding and clicking on specific numbers in a series of computer screens. The researchers also set up alternative tasks allowing students to choose to play video games or watch cartoons instead of trying to collect points. Most of the participants turned out to be workaholics who clicked away full time trying to gain points. Later the points could be exchanged for money, but in some cases the amount of money was randomly given a multiplier, so that some lucky participants ended up earning more than others who had been equally productive.

Once the game was over, kids from the same grade were paired and told how long each had spent earning points, how many they earned, and what multiplier each received. The pair's winnings were combined and one—the dictator—would decide how to divide up the total. What happened?

The Norwegian school kids, both male and female, divvied up the money with the mean share given to responders averaging around 45 percent across all grades. The researchers suggest that this nearly equal division results from the fact that "there is no apparent fairness argument justifying an unequal division of the money."

However, the researchers found that how students divided up money changed as they became older when it was earned and depended on individual achievements and luck. Most fifth graders (63 percent) remained strict egalitarians, dividing up the money equally, despite the fact that some players earned more money through individual achievement. However, the portion of egalitarians dropped to 40 percent by 7th grade; falling eventually to 22 percent by 13th grade. Conversely, the share of meritocrats rose from 5 percent in the fifth grade, to 22 percent in 7th grade, rising eventually to 42 percent in the 13th grade. A full 42 percent of players in the 13th grade kept more money for themselves because they believed that they have earned it. The authors of the Norwegian study conclude that the meritocratic fairness view increases as the cognitive abilities of children mature. In other words: yes, kids outgrow socialism.

The researchers also wanted to see if people are affected by efficiency considerations, so they set up the game so that some players' earnings could be multiplied by as much as a factor of four. In this case, the dictator can increase the overall total earned by the pair by giving his points to the responder. Younger kids don't take this multiplier effect into account, but as the age of male players increased, they were more willing to sacrifice points in order to increase the overall size of the pot. In other words, they choose to take less in order to maximize overall income.

In addition, the researchers found that in every grade about one-third of students do not find inequalities in earnings unfair, regardless of whether they are gained either through achievement or luck. They call this group "libertarians." Oddly, the study does not reveal how "libertarians" played the dictator game, though the overall average 45/55 percent split does not seem to have been greatly affected by their play. The researchers note, "Although there was a sharp decrease in the importance of the strict egalitarian fairness view, the prevalence of the libertarian fairness view was stable throughout adolescence." Whatever motivates them, it is clear is that they are not egalitarians.

University of Virginia moral psychologist Jonathan Haidt's research explores similar territory: the differences in ethical reasoning between liberals, conservatives, and libertarians. He argues that there are five dimensions along which people make moral choices, e.g., fairness, harm, loyalty, authority, and spiritual purity. Haidt finds that liberals focus chiefly on the first two dimensions, whereas conservatives deploy all five dimensions in their ethical reasoning.

At a recent lecture at the American Enterprise Institute, Haidt further refined the notion of fairness, asserting that there are three kinds of fairness. Liberals focus on one kind of fairness, where everyone's needs are met to some degree. Conservatives, by contrast, see fairness when people are rewarded for their efforts, e.g., what they put in, they get to take out. They also see retribution as a special kind of equity in which perpetrators of wrongs must suffer to the same degree as their victims, e.g., an eye for an eye.

What about libertarians? After his lecture, I asked Haidt where libertarians fit along the five moral dimensions. He asked me to guess how libertarians tested. "Like liberals," I said, by which I meant that libertarians, like liberals, are less concerned about group loyalty, obedience to authority, and purity. He laughed and said, "Yes, like liberals, but without compassion." Put another way, libertarians react like liberals, but without the concerns about egalitarianism that dominate the way liberals—and 10-year-olds—think about fairness.

Ronald Bailey is Reason's science correspondent. His book Liberation Biology: The Scientific and Moral Case for the Biotech Revolution is available from Prometheus Books.