The Secret Life of the Mind: How Our Brain Thinks, Feels and Decides. Mariano Sigman

the notion of money, usefulness and the prices of things.

      As in the adult world, not all transactions in the country of childhood are licit. There are thefts, scams and betrayals. Rousseau’s conjecture is that the rules of citizenship are learned in discord. And it is the playground, which is more innocuous than real life, that becomes the breeding ground in which to play at the game of law.

      The contrasting observations of Wynn and her colleagues suggest that very young children should already be able to sketch out moral reasoning. On the other hand, the work of Piaget, who is an heir to Rousseau’s tradition, indicates that moral reasoning only begins at around six or seven years old. Gustavo Faigenbaum and I set out to reconcile these different great thinkers in the history of psychology. And, along the way, to understand how children become citizens.

      We showed to a group of children between four and eight years of age a video with three characters: one had chocolates, the other asked to borrow them and the third stole them. Then we asked a series of questions to measure varying degrees of depth of moral comprehension; if they preferred to be friends with the one who stole or the one who borrowed^fn16 (and why), and what the thief had to do to make things right with the victim. In this way we were able to investigate the notion of justice in playground transactions.

      Our hypothesis was that the preference for the borrower over the thief, an implicit manifestation of moral preferences – as in Wynn’s experiments – should already be established even for the younger kids. And, to the contrary, the justification of these options and the understanding of what had to be done to compensate for the damage caused – as in Piaget’s experiments – should develop at a later stage. That is exactly what we proved. In the room with the four-year-olds, the children preferred to play with the borrower rather than with the thief. We also discovered that they preferred to play with someone who stole under extenuating circumstances than with aggravating ones.

      But our most interesting finding was this: when we asked four-year-old children why they chose the borrower over the thief or the one who robbed in extenuating circumstances over the one who did so in aggravating ones, they gave responses like ‘Because he’s blond’ or ‘Because I want her to be my friend.’ Their moral criteria seemed completely blind to causes and reasons.

      Here we find again an idea which has appeared several times in this chapter. Children have very early (often innate) intuitions – what the developmental psychologists Liz Spelke and Susan Carey refer to as core knowledge. These intuitions are revealed in very specific experimental circumstances, in which children direct their gaze or are asked to choose between two alternatives. But core knowledge is not accessible on demand in most real-life situations where it may be needed. This is because at a younger age core knowledge cannot be accessed explicitly and represented in words or concrete symbols.

      Specifically, in the domain of morality, our results show that children have from a very young age intuitions about ownership which allow them to understand whether a transaction is licit or not. They understand the notion of theft, and they even comprehend subtle considerations which extenuate or aggravate it. These intuitions serve as a scaffold to forge, later in development, a formal and explicit understanding of justice.

      But every experiment comes with its own surprises, revealing unexpected aspects of reality. This one was no exception. Gustavo and I came up with the experiment to study the price of theft. Our intuition was that the children would respond that the chocolate thief should give back the two they stole plus a few more as compensation for the damages. But that didn’t happen. The vast majority of the children felt that the thief had to return exactly the two chocolates that had been stolen. What’s more, the older the kids, the higher the fraction of those who advocated an exact restitution. Our hypothesis was mistaken. Children are much more morally dignified than we had imagined. They understood that the thieves had done wrong, that they would have to make up for it by returning what they’d stolen along with an apology. But the moral cost of the theft could not be resolved in kind, with the stolen merchandise. In the children’s justice, there was no reparation that absolved the crime.

      If we think about the children’s transactions as a toy model of international law, this result, in hindsight, is extraordinary. An implicit, though not always respected, norm of international conflict resolution is that there should be no escalation in reprisal. And the reason is simple. If someone steals two and, in order to settle a peace, the victim demands four, the exponential growth of reprisals would be harmful for everyone. Children seem to understand that even in war there ought to be rules.

Jacques, innatism, genes, biology, culture and an image

      Jacques Mehler is one of many Argentinian political and intellectual exiles. He studied with Noam Chomsky at the Massachusetts Institute of Technology (MIT) at the heart of the cognitive revolution. From there he went to Oxford and then France, where he was the founder of the extraordinary school of cognitive science in Paris. He was exiled not just as a person, but as a thinker. He was accused of being a reactionary for claiming that human thought had a biological foundation. It was the oft-mentioned divorce between human sciences and exact sciences, which in psychology was particularly marked. I like to think of this book as an ode to and an acknowledgment of Jacques’s career. A space of freedom earned by an effort that he began, swimming against the tide. An exercise in dialogue.

      In the epic task of understanding human thought, the division between biology, psychology and neuroscience is a mere declaration of caste. Nature doesn’t care a fig for such artificial barriers between types of knowledge. As a result, throughout this chapter, I have interspersed biological arguments, such as the development of the frontal cortex, with cognitive arguments, such as the early development of moral notions. In other examples, like that of bilingualism and attention, we’ve delved into how those arguments combine.

      Our brains today are practically identical to those of at least 60,000 years ago, when modern man migrated from Africa and culture was completely different. This shows that individuals’ paths and potential for expression are forged within their social niches. One of the arguments of this book is that it is also virtually impossible to understand human behaviour without taking into consideration the traits of the organ that comprises it: the brain. The way in which social knowledge and biological knowledge interact and complement each other depends, obviously, on each case and its circumstances. There are some cases in which biological constitution is decisive. And others are determined primarily by culture and the social fabric. It is not very different from what happens with the rest of the body. Physiologists and coaches know that physical fitness can change enormously during our life while, on the other hand, our running speed, for example, doesn’t have such a wide range of variation.

      The biological and the cultural are always intrinsically related. And not in a linear manner. In fact, a completely unfounded intuition is that biology precedes behaviour, that there is an innate biological predisposition that can later follow, through the effect of culture, different trajectories. That is not true; the social fabric affects the very biology of the brain. This is clear in a dramatic example observed in the brains of two three-year-old children. One is raised with affection in a normal environment while the other lacks emotional, educational and social stability. The brain of the latter is not only abnormally small but its ventricles, the cavities through which cerebrospinal fluid flows, have an abnormal size as well.

      So different social experiences result in completely distinct brains. A caress, a word, an image – every life experience leaves a trace in the brain. These traces modify the brain and, with it, one’s way of responding to things, one’s predisposition to relating to someone, one’s desires, wishes and dreams. In other words, the social context changes the brain, and this in turn defines who we are as social beings.

      A second unfounded intuition is thinking that because something is biological it is unchangeable. Again, this is simply not true. For instance, the predisposition to music depends on the biological constitution of the auditory cortex. This is a causal relation between an organ and a cultural expression. However, this connection does not imply developmental determinism. The auditory