Human beings may be a savage species when we want to be, but we’re also an exceedingly moral one, with a highly evolved sense of right and wrong, good and bad, crime and consequences. This is best illustrated by our third-party penalty system: penalizing malefactors who do us no harm. Judges and juries are responsible for punishing those who wrong others. This is the foundation of civil and criminal justice.
An instinct for third-party punishment appears early in life—think of preschoolers tattling on classmates who have broken a rule or taken a toy from someone else—but just how early has been unclear. In June, there was a new study. Nature Human BehaviorThe answer is in the question. According to research led by investigators from Osaka University and Otsuma Women’s University, in Japan, third-party punishment behavior may begin in babies as young as 8 months old. The researchers say it’s evidence that morality may be innate.
Since it is impossible to know what’s going on in a pre-verbal baby’s head by asking them, the study involved familiarizing 24 8-month-old babies with a simple video game, in which anthropomorphized shapes—squares with eyes drawn onto them—move about a screen interacting with one another. Where the babies’ own eyes moved was recorded by a gaze-tracking device, and as the babies watched the shapes move, they learned an important feature of the game: if they let their gaze linger on one figure for long enough, a square without eyes would fall from the top of the screen and crush it.
The researchers added complexity to the game after the baby had successfully learned the feature. As the babies watched, the researchers added more complexity to the game by making it possible for one square with eyes to collide with another and smashing against the screen. After several such incidents, the babies started to respond, with roughly 75% of them directing their gaze at the wrongdoer and holding it there until the crushing square would fall from the sky and destroy it—effectively administering a penalty for its misbehavior.
“The results were surprising,” said lead author Yasushiro Kanakogi in a statement that accompanied the study’s release. “We found that preverbal infants chose to punish the antisocial aggressor by increasing their gaze toward the aggressor.”
But, the study did not prove this, and there was a lot of other possibilities. Imagine, for instance, that they were not intending to punish the aggressor; rather, their attention was drawn to the square which was the active one on the screen. To test that theory, the investigators trained another 24 babies of the same age on a game in which a square would still fall on the aggressor, but it would fall slowly and harmlessly, without crushing—or punishing—it. The same experiment was repeated under these conditions. Babies stared less predictably at wrongdoers, and the percentage who did so fell to 50% or lower.
Similar results were obtained when researchers ran the variations of the study again with another group of 24 babies. In one trial, gazing at the wrongdoer caused the crushing square to fall only half the time—making the punishment less reliable. Another trial saw the eyes removed from character squares to make them more anthropomorphic. In both of those trials too, the babies’ gazed much less frequently at the malefactor after it misbehaved. Researchers recruited yet another group of babies to rerun the original experiment. The squares that were anthropomorphized by the researchers got crushed whenever the babies looked at them. As expected, the babies responded by looking at misbehaving characters more often than in the original experiment. They were acting as judge or jury in order to decide if they liked what was being shown.
Researchers believe that the results show that the possibility of third-party punishing is more learned than evolved. This is a result of an universal moral grammar many ethicists and psychologists think human beings were born with.
“The observation of this behavior in very young children indicates that humans may have acquired behavioral tendencies toward moral behavior during the course of evolution,” Kanakogi said in a statement. “Specifically, the punishment of antisocial behavior may have evolved as an important element of human cooperation.”
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