Source: Louis Putterman

In The Secret of Our Success (2015), anthropologist Joseph Henrich shows convincingly just how dependent human technological and social progress has been on the cooperative creation and accumulation of know-how over the course of many generations. In The Social Conquest of Earth, biologist and originator of E.O. Wilson showed equally convincingly that it’s the unusually social nature of humans that accounts for their spread from Africa to every continent and their ever-greater (and ultimately endangering) domination of earth’s resources. Earlier, Robert Wright, in The Moral Animal, and Matt Ridley, in The Origin of Virtue, provided excellent lay scientific takes on the evolution of human using mainly evolutionary psychological lenses. Good Natured and Our Inner Ape are a few of the wonderful books by primatologist Franz de Waal which explore the emotional, social and cognitive similarities between humans and our closest primate relatives. These are some of the books that a lowly behavioral economist like myself has learned most from about human nature and its origins, and that I never tire of recommending to students who want to go beyond the stick figure Economic Man and a still somewhat inward-looking .

January 2019 strikes me as a milestone in our emerging understanding of these topics thanks to the publication that month of Michael Tomasello’s new book Becoming Human: A Theory of Ontogeny. I had encountered Tomasello’s student and collaborator, Felix Warneken, and had learned a bit about their research on the emergence of in young children—but I had not recognized the breadth and fundamental importance of Tomasello’s research to the scientific understanding of human sociality until Becoming Human arrived.

Tomasello is the scholar who puts toddlers in labs doubling as safe, pleasant environments for play, then sends adult collaborators into the room to drop a wad of papers or a pencil, fumble with opening a cabinet door, or engage in a similar ruse, whereupon he observes that the toddler tries to help the adult even if the adult pays no to the toddler. By varying the situation, he demonstrates convincingly that this is in no way strengthened if the parent is in the room, if the parent encourages it, if the parent praises it, etc. An urge to help a non-threatening adult when this age is evidently innate. Tomasello and collaborators have studied carefully at exactly what age it appears, and have demonstrated the absence of a comparable tendency in our closest relatives, chimpanzees and bonobos, regardless of whether wild, zoo residing, or human raised.

Most remarkably, he provides an abundance of evidence that from nine months to three years, the maturing toddler is driven by instinctual need to forge bonds with one or more adults and to develop a sense of me/you mutuality and give and take. This strong urge to enter into relationship also has no counterpart of its intensity and depth in other primates. Yes, they spend hours pulling vermin out of each others’ fur and do so mutually with preferred pals, but staring deeply into one another’s eyes for reassurance of mutual recognition isn’t in their repertoire.

Until age three, the normally developing human toddler is largely incapable of similar connection to any peer; put in a room together, two toddlers essentially play in parallel. But after age three, the toddler transitions to seeking out playmates and wishing, with the same intensity as with the earlier toddler-adult bonds, to enter into play with peers as part of a “we” in which norms of fairness, respect, and reciprocity emerge spontaneously without adult guidance. In both dual and group relationships, the normally developing individual internalizes her obligation to the other or others and therefore feels it is right for her to be punished if she violates a norm or rule.

Important to this narrative is its treatment of the emergence of self-consciousness as a function of the growing awareness of how one appears to others. The normally developing individual internalizes his knowledge of how she judges others in the group based on their degree of adherence to group norms, including ones of moral right and wrong (what is good for us, and not necessarily privately best for me). The individual then gradually transforms this into an awareness that she herself is being judged by other group members, and from there to “ and of .” Note well that both maturation of genetically-based capacities and interaction with a culturally rich social environment are needed to permit development of the maturing human child. Human capacities that have fairly close ape analogues are reported to come on line at earlier ages, despite humans being born less neurologically mature. And more importantly, there are evolved human capacities that don’t exist in the apes and that can’t be coaxed out of them by any amount of interaction with humans. These specifically human capacities also wouldn’t “ripen” into full human sociality without the social context—healthy maturation won’t occur on the proverbial desert island or in a human raised by animals or in a Ceauşescu-era Romanian orphanage with no adult TLC.

Why is Becoming Human such an important contribution to the emerging literature on human nature? The answer is that until now, writers on human uniqueness, human sociality, and their evolution via the forces of natural selection during the several million years since our ancestors’ separation from the lineages that became our fellow apes, have largely ignored the evidence that Tomasello and others have been extracting from the study of human child development and of the early years of our ape counterparts. Lacking this element, many have emphasized the importance of and sociality, yet left open the possibility that the creation of shared human knowledge and culture are sufficiently explained by cooperative psychological dispositions, sensitivity to our social environments, and large brains capable of handling the massive information flows of our socio-cultural milieu. Put differntly, the cognitive capabilities of the maturing brain and the presence of a still accumulating body of language, narratives, and information outside of that brain seem to be enough to cause the normal human child to grow up to become a member of his or her culture, without need of added drives from within. Tomasello argues convincingly that all of that brain complexity inside the skull and all of the cultural complexity outside the skull would not produce humans like ourselves if the need to reach out and form bonds with others were not also there, emerging pre-programmed as a powerful drive. The approach remains fully consistent with the -culture co-evolution ideas of Boyd, Richerson, Henrich, Wilson, and others—the need to reach out can indeed have been selected for via feedback loops as human sociality and began to grow and make such a need advantageous—but I believe that these writers whom I admire so much had not heretofore articulated adequately the ideas in the ontogenetic approach of Tomasello.

Yes, we scientists too feel an innate need to dialogue with one another. Were it not for our need to reach out and contribute, books like those I've discussed above would not emerge. Three cheers for the will to engage. And may a little child lead the way.