What makes humans unique?
Posted by gregdowney on May 25, 2008
Prof. Michael Tomasello, co-director of the Max Planck Institute for Evolutionary Anthropology, whose work on chimpanzees and human children, on the biological capacity for culture, and a range of other subjects, must place him among the most important contemporary thinkers using comparative primate data, asks ‘How Are Humans Unique?’ in a recent piece for The New York Times‘ Idea Lab.
As Tomasello suggests, many things that we thought once definitively marked the difference between humans and other species, have gradually been found in evidence in other species — tools, deductive learning, language, even certain patterns of anti-social behaviour suggesting war and the like. The result is, for some, an uneasy sense that we might not be so different from other animals, and for others, a satisfaction that humans might be thought about using analytical frames developed with other species.
One thing that Tomasello points out very well is that many of humans’ cognitive advantages over other intelligent animals are ‘products of collective cognition,’ that is, not so much just an individual’s ability as the ability of an individual invested with the collective creativity and mental tricks invented by previous generations of humans.
This is a point that philosopher Merlin Donald also makes very well in his work, A Mind So Rare: The Evolution of Human Consciousness (Amazon). As Donald writes in the preface to the work:
This book proposes that the human mind is unlike any other on this planet, not because of its biology, which is not qualitatively unique, but because of its ability to generate and assimilate culture. The human mind is thus a “hybrid” product of biology and culture.
In Tomasello’s NYT piece, he points out that tests run on two-year-olds as well as other adult orangutans and chimpanzees showed that the human kids weren’t necessarily all that much smarter about the world.
However, the two-year-olds were much better at certain kinds of social cognition: ‘social learning, communicating and reading the intentions of others.’ In isolation, especially deprived of the ‘products of collective cognition,’ Tomasello suggests that we wouldn’t see humans as all that impressive in relation to other species. But put into social situations, humans’ exceptional abilities start to stand out:
When you look at apes and children in situations requiring them to put their heads together, a subtle but significant difference emerges. We have observed that children, but not chimpanzees, expect and even demand that others who have committed themselves to a joint activity stay involved and not shirk their duties. When children want to opt out of an activity, they recognize the existence of an obligation to help the group — they know that they must, in their own way, “take leave” to make amends. Humans structure their collaborative actions with joint goals and shared commitments.
Turns out that human infants communicate, not only to get what they want (as other primates do), but simply because they seem to enjoy communicating. Humans’ prodigious ability to communicate, and their propensity to share information even without immediate instrumental goals, creates an entirely different environment in which to think, learn, and teach.
Tomasello also highlights the human ability to agree upon fictions — to pretend — because it ends up supporting the ability to create institutions, social roles, and complex forms of organization.
Human beings have evolved to coordinate complex activities, to gossip and to playact together. It is because they are adapted for such cultural activities — and not because of their cleverness as individuals — that human beings are able to do so many exceptionally complex and impressive things.
In general, I agree with Tomasello on many levels, and his more expansive versions of this argument are well worth reading (such as The Cultural Origins of Human Cognition). One danger is that, because the human brain is so profoundly encultured, we tend to forget that many human cognitive capacities are introjected social achievements.
The most obvious case of this is when theorists point to parts of the brain associated with language and argue that languages ‘come from’ one brain region or another. As the tragic cases of feral children and the victims of profound neglect demonstrate, language does not ‘come from’ an isolated brain — it comes from the social context of communication. Even those small groups of children who ‘invent’ languages do so as groups, not as individuals. Tomasello’s piece highlights that it is the social intelligence of the human brain which, compounded through the types of cooperation it supports, starts to look like a massive gap in individual organic intelligence.
But one of the things that I’ve been struck by in several versions of this argument (call it the ‘encultured mind’ argument) is that it could also be said about the human body; outside of a socialization process, the human body, nervous system, and physical abilities would be radically different, not just the brain and cognition. Most of our physical abilities require modeling, even the ways that we walk and perform very basic physical tasks.
In fact, humans physical abilities are also quite startling in relation to the physical abilities of other species. Because of our deep-seated ideas about how human distinctiveness is primarily superior intelligence, we fail to notice that physical trainability is also terribly unusual in humans. The gap between average performance and exceptional performance in our species is great; in other species, such variability is not observed. And much of the variability is produced socially, through coaching, shared experimentation, external incentives, and other cooperative forms of enhancing individual ability. In other words, the same social intelligence that Tomasello points to as the root of human cognitive difference is also the foundation for the ability of humans to produce exceptional physical performance in a range of activities.
Photo by Jo. Thanks.