by Matthew Syed
Techniques such as cooking actually increase the energy available from foods and make them easier to digest and detoxify. This effect allowed natural selection to save substantial amounts of energy by reducing our gut tissue . . . This externalisation of digestive functions by cultural evolution became one component in a suite of adjustments that permitted our species to build and run bigger brains.2
Or take the fact that humans are among the greatest endurance runners on earth. We can hunt down antelopes and the like, particularly in hot weather. We have a number of traits that enable us to do this, in particular our impressive capacity to perspire. We can sweat one to two litres per hour, which is a wonderful cooling mechanism.
But this raises a puzzle: our stomachs are too small to take in the large quantities of water required to sustain running over long distances. How, then, do we keep going with such inadequate storage? Why do we sweat so profusely when we cannot take on enough water in the first place? The puzzle is only solved when you factor in technology. Once we learned how to carry water in gourds, skins and ostrich eggs, and this technology became a stable part of our environment, passed down the generations, we didn’t need a large storage system in our bodies. We outsourced water storage just as we outsourced food detoxification, leading to a different evolutionary trajectory.
But note, once again, the direction of causality. Our efficient distance-running adaptations could not have evolved without the prior technology for external storage. As Henrich puts it: ‘The evolution of our complex, and rather extraordinary sweat-based thermoregulatory system could only happen after we have developed the idea of making water containers (and locating water sources).’
Our ideas and technologies do not merely change our genes; they also modify our biology in a non-genetic way. The fact that you are reading these words mean that you are literate. You have learned the technique of reading from your parents and teachers who, in turn, learned it from theirs. But in acquiring the ability to read, you also modified your brain. Learning to read changes the left ventral occipital temporal region of your brain, thickens the corpus callosum, modifies the superior temporal sulcus and inferior prefrontal cortex. This rewiring of the brain that occurs through the process of learning how to read is a biological modification associated with literate societies, but it is not a genetic modification. As Henrich says:
Reading is a cultural evolutionary product that actually rewires our brains to create . . . an almost magical ability to rapidly turn patterns of shapes into language. Most human societies have not had a writing system, and until the last few hundred years, most people did not know how to read or write. This means that most people in modern societies (those with high reading proficiency) . . . have different brains with somewhat different cognitive abilities than most people in most societies across human history . . . The crucial point is that cultural differences are biological differences but not genetic differences.
These are just a few examples of the ways in which rebel ideas have directly shaped our brains and bodies, and, indeed, social norms and institutions. They have also shaped our psychology. Once we could learn more from our social group than we could ever learn in a lifetime on our own, natural selection started to favour those who were skilled at extracting ideas from other brains. This meant the ability to pay attention to those from whom we had the most to learn. As Henrich puts it:
Once [ideas] began to accumulate . . . the main selection pressure on genes revolved around improving our psychological abilities to acquire, store, process and organise the array of fitness-enhancing skills and practices that increasingly became available in the minds of the others in one’s group . . . This process can be described as autocatalytic, meaning that it produces the fuel that propels it.
III
This admittedly cursory survey of human evolution provides us with the ultimate contrast between the individual and holistic perspectives. The human brain is impressive, but the success of the human species consists in the intricate web of connections, stretching across the planet and back through history, which has led to the evolution of a vast body of ideas, technologies and culture. For an estimated two million years this has guided the process of human genetic evolution, expanding the brain, altering our physiology, and feeding back into the body of ideas.
Our species is, in this sense, constructed upon diversity. Our species is unique in the way that different ideas, experiences, lucky discoveries and recombinations sweep through our social networks, building the collective brain, expanding collective intelligence and altering the trajectory of natural selection. It is the diversity of these ideas that make us smart. Stripped of the cumulative body of ideas, the naked human brain is far less impressive.
Indeed, anthropologists have created experiments that seek to measure naked human cognitive capacity (i.e. when deprived of access to the body of cumulative information). One way to do this is by comparing human toddlers with similarly aged chimps and other primates. At this stage of development, human toddlers have absorbed quite a bit of information from their parents, but far less than children of ten or even five. A study by researchers at the Institute for Evolutionary Anthropology in Leipzig placed human toddlers (two and a half years old) against chimpanzees and orang-utans in tests of spatial memory (subjects had to recall the location of an object), causality (assessing shapes and sounds) and other cognitive tasks. The results were pretty much identical across all challenges. The humans and chimps performed at about the same level, with the orang-utans slightly behind.
The one task that the humans excelled at, however, was social learning. This involved observing a demonstrator use a complex technique to extract food from a narrow tube. The human children picked up the technique right away, and were able to apply it instantly. The other primates were unable to make sense of what they had seen, or put it into practice. Henrich writes:
On the social learning subtest, most of the two and a half year old humans scored 100% on the test, whereas most of the apes scored 0%. Overall, these findings suggest that the only exceptional cognitive ability possessed by young children in comparison to two other great apes relates to social learning and not to space, quantities, or causality.
This may sound counterintuitive but it maps onto what we have learned. Humans are smart because we have evolved to connect with other brains. This is why a human child by the age of nine or ten can beat any other primate of any age on pretty much any of the cognitive tasks in the experiment. The body of knowledge absorbed from adults equips the brain with outsized power.
Chimps and orang-utans do not improve as they get older. Once their brains have reached maturity at age three, that is as good as they will ever get. There is no collective brain to plug into, no corpus of ideas, no cumulative culture. And, even if there were, they have not developed the mental capacities to extract this information from other animals because in their evolutionary history there was no selection pressure to build such capacities. Michael Muthukrishna sums it up: ‘Why is it that humans are so different from other animals? It’s not because of our hardware. It’s not because we have these giant brains that make us more intelligent than other animals. In fact, some chimpanzees can beat us on basic working memory tasks . . . What makes us different from other animals is our collective brain.’ Kevin Laland writes: ‘humanity’s success is sometimes credited to our cleverness, but [ideas] are actually what make us smart. Intelligence is not irrelevant, of course, but what singles out our species is an ability to pool our insights and knowledge, and build on each other’s solutions.’3
This analysis may seem a little disparaging of the individual human brain. After all, it is considered the most complex entity in the known universe. We are proud of our cognition and processing. But the underlying point can be made using the brain itself as a metaphor. The brain is composed of innumerable neurons and axons. It is a complex system comprised of a multitude of different parts. And yet the intelligence of any given brain does not emerge from t
he intelligence of its parts. No single neuron is responsible for coming up with an insight. Rather, the brain’s power is based upon the interaction of its parts. As Marvin Minsky writes in The Society of Mind, ‘you can build a mind from many little parts, each mindless by itself’.
The individual brain stands in relation to the collective brain somewhat as the neuron stands in relation to the individual brain. The metaphor isn’t precise since individual brains do come up with insights on their own. Unlike neurons, they are not dumb. But the conceptual point stands: whether we are operating in normal time (measured in minutes, hours, years and centuries) or evolutionary time (measured in hundreds of thousands of years), human development relies on the way diverse brains interact far more than on the constituent brains themselves.
We are left with a scintillating vision. Our species is the most formidable on the planet not because we are individually formidable, but because we are collectively diverse. By bringing different insights together, by connecting within and across generations, by recombining rebel ideas, we have created innovations of a quite breathtaking kind. It is our sociality that drove our smartness, not the other way around.
Diversity is not merely the ingredient that drives the collective intelligence of human groups, it is also the hidden ingredient that has driven the unique evolutionary pathway of our species. It is, to quote Henrich, the secret of our success.
IV
Having looked at the big picture, let’s narrow the focus for a final time to see more ways that we can wield the lessons of this book in practice. How can we harness diversity in our jobs and in our lives? We will look at three final applications, all of which have immediate relevance to how we live, work and structure societies.
Unconscious Bias
Unconscious bias dominates many contemporary debates on diversity. This refers to the way that people are denied opportunities not because of a lack of talent or potential but because of arbitrary factors such as race or gender.
Perhaps the most intuitive example of unconscious bias emerged in the 1970s. At that point, orchestras in the United States (and elsewhere) were dominated by men. The reason is simple: those who conducted the auditions thought that men were, typically, better musicians. This was a meritocracy, they insisted. Men were said to be more accomplished pianists, violinists, etc.
But Claudia Goldin of Harvard and Cecilia Rose of Princeton had an idea: why not conduct auditions behind screens? This meant that the selection panels could hear the music, and assess its quality, but could not see the gender of the musicians playing it. When these screens were introduced, women’s chances of making it through the first round increased by 50 per cent, and in the final rounds by 300 per cent. Female players in major orchestras have since increased from 5 per cent to nearly 40 per cent.
What is fascinating is that the recruiters didn’t realise they were discriminating against women until the screen was introduced. Only then could they see that they had been assessing candidates not merely on skill, but through the filter of stereotypes about what a good musician ought to look like. Eliminating bias was not just good for female musicians, but also for orchestras. They were recruiting talent regardless of what it looked like.
Unconscious bias tends not to manifest itself when the differences between candidates are obvious. After all, why would an employer deliberately choose an inferior performer? This would harm the organisation itself. It is only when candidates are similar in ability, when the recruiter has what psychologists call ‘discretionary space’, that unconscious bias takes on greater significance.
Take a study where university students were given the task of deciding between candidates for a job. When black candidates were clearly superior to white candidates, they were almost always selected. The same was true of the white candidates. It was only when the CVs were similar in quality that unconscious bias kicked in. At this point, students showed a small, but significant, tendency to go for white candidates. They did not do so consciously. They were surprised when the bias was pointed out to them. Had any given decision been challenged in court, discrimination would have been nigh impossible to prove. And yet the stereotype that black people are of lower ability than whites influenced the way they unconsciously processed the CVs.
It is the cumulative consequences of these small biases that are so significant. For to make it anywhere in life requires going through a series of sliding-door evaluations. You have to gain selection to the school debating team, to the summer internship, to university, to secure your first job, to gain promotion and so on. These are merely the headline examples. Evaluations are baked into almost all of our daily interactions.
But now think of the mathematics of such a sequence. Just a 10 per cent bias against black people in each of ten evaluations reduces their probability of getting to the top by a massive 90 per cent, a point made by Scott Page. Consider, too, how this creates perverse incentives. For in order to attain credentials in the first place requires hard work and sacrifice, not just at school and university but beyond. Success requires a willingness to defer gratification in myriad ways.4
And yet if the pay-off associated with these credentials is so grievously diluted, why would one bother to put in the hard yards? Roland Fryer, the Harvard economist, has shown just how distorted the pay-offs to education can become for minority groups. And this hints at what has become known as structural bias: the way that the legacy of historical injustice, unconscious discrimination and skewed incentives can harden into concrete barriers for certain sections of the population.
Dismantling unconscious bias, then, is not just a powerful first step in creating a fairer system; it is also a first step in creating a more collectively intelligent society. It gives people from all backgrounds a chance to pursue their talents, broadening the body of people with the knowledge to contribute to our most pressing challenges. Combatting structural discrimination should be near the top of any political agenda.
And this takes us back to the screens in the orchestra auditions. These were effective because they took the subjectivity out of recruiting. Biases were removed through the design of the evaluation itself. They had deeper effects, too, giving aspiring female musicians the confidence that their talent would be fairly evaluated – thus conferring a bigger incentive to gain the qualifications in the first place.
In her book What Works, the Harvard academic Iris Bohnet offers an extensive analysis of different measures to bolster the objectivity of evaluations. These include ‘blinding’ CVs (by removing certain types of demographic information), altering the way companies search for new recruits, how they advertise positions, where they post job openings, how they evaluate applicants, how they create short lists, how they interview candidates, and how they make their final selections.5
Yet while eliminating unconscious bias is a vital technique when it comes to enlarging collective intelligence, it is by no means sufficient. Think back to Bletchley Park. Suppose that the recruiters had been keen to hire mathematicians. By removing unconscious bias, they would have been in a position to identify the top mathematicians uncorrupted by stereotypes.
And yet this would have not helped them find crossword experts and other idiosyncratic minds that turned out to be so crucial to cracking the Enigma. Eliminating unconscious bias assists with finding the best individuals regardless of race or gender. But it doesn’t – in and of itself – optimise cognitive diversity. These two challenges are conceptually distinct. Great organisations need to do both.
Shadow Boards
Another way that cutting-edge companies are harnessing diversity is through the use of ‘shadow boards’. These consist of young people who advise executives on key decisions and strategies, thus lifting the conceptual blinkers that can attach to age. After all, each of us grew up at a particular time, and absorbed a particular cultural and intellectual paradigm. This influences the way we think in so many ways that we can become unconscious of it.
Indeed, this applies a
s much to science as to anything else, a point that has been made by the philosopher Thomas Kuhn. Practising scientists often operate according to a particular set of assumptions and implicit theories, something that can place constraints on the development of new insights. This is what prompted the great physicist Max Planck to say: ‘science advances one funeral at a time’.
Shadow boards typically consist of a group of the most able young people, drawn from across an organisation, who have regular input into high level decision-making. This enables executives to ‘leverage the younger groups’ insights and to diversify the perspectives that executives are exposed to.’ This, in turn, drives a greater flow of rebel ideas.
Anyone who has struggled with a new technology, and been amazed at how quickly younger people take to it, will grasp the significance of a shadow board. Anyone who has been struck by how differently young people can think about old problems will also grasp the logic. And this is why it should be no surprise that companies that have created shadow boards, and integrated them into high-level decision-making, have reaped vast rewards.
A paper in the Harvard Business Review by the management experts Jennifer Jordan and Michael Sorell contrasted the fortunes of Prada and Gucci, two high-end fashion brands. Prada has traditionally enjoyed high margins, but experienced a slump between 2014 and 2017. Why? A public announcement in 2018 acknowledged that the company had been ‘slow in realizing the importance of digital channels and the blogging online ‘‘influencers’’ which are disrupting the industry.’ CEO Patrizio Bertelli said: ‘We made a mistake.’
As for Gucci, they created a shadow board of young people who had consistent interaction with the senior team. ‘They talk through the issues that the executive committee is focused on and their insights have ‘‘served as a wakeup call for the executives.’’ Gucci’s sales have since grown 136% – from 3,497 million Euro (FY2014) to 8,285 million Euro (FY2018) – a growth driven largely by the success of both its internet and digital strategies. In the same period, Prada’s sales have dropped by 11.5%, from 3,551 million Euro (FY2014) to 3,142 million Euro (FY2018).’6