The conventional approach to intelligence has been to rely only on our own personal mental capabilities. 

We tend to assume that intelligence resides only in our skulls, the same way the computation of a computer is sealed inside its aluminum case.

But in her book The Extended Mind (affiliate link) Annie Murphy Paul argues otherwise: that our mind is more like an eclectic bird’s nest, pieced together out of myriad odds and ends we’ve gathered from our environment.

Her book is a fantastic deep-dive into the latest science behind “extended cognition” – the ability of humans and other animals to extend and amplify their intelligence using their environment. 

She opens with a critique of our society’s longstanding “neurocentric bias”: how in most of our efforts to “improve our thinking,” we focus all our attention on our heads – committing information to memory, exercising our self-discipline, or rooting out cognitive biases. This excessive “cognitive individualism” leads us to repeatedly try to solve problems using only a fraction of the intelligence available to us.

Where does that unutilized intelligence reside? In our bodies, environments, and relationships primarily. These “extra-neural inputs” allow us to transcend the limits of our own biology.

The smarter approach is to learn to reach beyond our brain’s limitations to the vast array of intelligences lying just beyond the walls of our skull.

The Complexity of the World Has Exceeded Our Brain’s Capacity

The modern world has grown extraordinarily complex, far beyond anything our minds evolved to handle. Everyday life revolves around non-intuitive concepts, layer upon layer of abstractions, with reality mediated by countless concepts and symbols.

We were not born to understand the intricacies of engineering or calculus. We did not evolve to master the global financial markets or the complexity of climate change. We have more information coming at us than ever, but that information is ever more specialized and abstract.

Succeeding in such a world requires a range of mental abilities: focused attention, expansive memory, plentiful bandwidth, sustained motivation, logical rigor, and the ability to learn new skills quickly. Sometimes we display those abilities, but as the world accelerates, increasingly we can’t keep up.

With every additional terabyte of data swelling humanity’s store of available knowledge, our native human abilities fall further behind. We need a new way of expanding our intelligence and keeping up with the pace of change.

The Extended Perspective – Going Beyond the Limits of Our Brains

In 1995, two British philosophers, Andy Clark and David Chalmers, published a scientific paper that would go on to revolutionize our understanding of cognition. It was called “The Extended Mind,” and it proposed a radical hypothesis: that our mind doesn’t end at the limits of our skull, but instead naturally “extends” into our surroundings.

In this view, experts are not those who maximize their own brains, but those who have learned how to leverage extra-neural resources to accomplish the task at hand. They have discovered how to offload and externalize information from their own brains, and then dynamically interact with those external manifestations of knowledge in ways that are impossible using only neurons.

Intelligence is thus an act of continuous assembly and reassembly of resources external to the brain.

Clark and Chalmers’ viewpoint was initially ridiculed in many circles. But in the following years scientific discoveries on three different fronts confirmed many of their ideas: embodied cognition (which explores the role of the body in our thinking); situated cognition (which examines the influence of our environment on thinking); and distributed cognition (how groups of people can draw on their collective intelligence).

Paul places each of these frontiers under the unified umbrella of extended cognition, and dedicates her book to exploring them.

Embodied Cognition – Thinking with the Body

Whereas language is discrete and linear, gesture is impressionistic and holistic, conveying an immediate sense of how things look and feel that speaks directly to the intuition of others. 

One study found that subjects were 33% more likely to recall a point from a presentation if it was accompanied by a gesture. And that memory effect grew more pronounced as time passed, increasing to 50% just 30 minutes after watching the talk. 

Instructional videos that include gesture significantly enhance learning – viewers direct their gaze more efficiently, pay more attention to essential information, and more readily transfer what they learn to new situations. There are benefits to the speaker as well – making gestures causes them to speak more fluently and articulately, make fewer mistakes, and present information in a more logical and intelligible way.

By learning to recognize the bodily sensations that indicate our body “knows” something, we can tap into subconscious sources of knowledge. Engaging in physical activities or movement as we communicate can help us uncover new insights, ideas, and perspectives that our conscious minds might have otherwise missed.


Situated Cognition – Thinking with Space

When people occupy spaces that they consider their own, the research says, they experience themselves as more confident and capable. And they not only feel that way, they actually perform more productively, efficiently, and with more focus and less distractibility.

Barbara Tversky, a professor of psychology and education at Teachers College in New York, observes that “We are far better and more experienced at spatial thinking than at abstract thinking.” By offloading our ideas onto our environment, “…spatial thinking can substitute for and scaffold abstract thought.”

Something as simple as writing down a phone number to better remember it is a powerful way of quickly offloading information from our brains and freeing up mental bandwidth. This effect is especially powerful when it comes to creative work: artists, architects, and designers report that they often “discover” elements in their own work that they didn’t “put there.” 

By writing or sketching something down, we are carrying on a conversation between our hand, our eye, and our mind out of which can emerge something greater than the sum of those parts.

The use of visual artifacts such as charts, diagrams, maps, models, and photos has also been shown to make people gesture more, in reference to those artifacts. Thus the use of our body (described above) and the use of space go hand in hand.

Distributed Cognition – Thinking with Others

Kevin Laland, a professor of biology at the University of St. Andrews in the UK, once hosted a competition pitting computer bots against each other in a battle royale tournament.

A hundred contestants from around the world faced off, with their bots programmed to pursue one of three different strategies: invent original ideas, engage in trial and error, or copy others.

To his surprise, one strategy was a clear winner across the board: copying others. The winning bot exclusively copied the winning moves of others, and never innovated on its own. By comparison, another bot that relied completely on innovation finished 95th out of 100.

Their conclusion was that imitation is often one of the most efficient and effective learning strategies. By waiting for others to try out new approaches and discover whether they work, you can reap most of the rewards of innovation without incurring most of the costs. Imitators are free to borrow from multiple sources, giving them a wider variety of tools to work with. And they can avoid mistakes by purposefully steering clear of strategies that others have found do not work.

Studies from the business world indicate that the costs for an imitator are typically 25% to 40% lower than those of an innovator, while still allowing them to reap most of the rewards.

Engaging in effective imitation is like receiving a direct download of experience from someone else’s brain. But despite its reputation as a lazy shortcut, imitation is not easy. It requires deeply understanding a solution and adapting it to a new set of circumstances. Ironically, imitating well demands a high degree of creativity. The Internet has ushered in a “golden age of imitation” in which it has become far easier than ever before to imitate quickly and widely from the vast array of knowledge we have access to online.

A 2019 study published by the National Academy of Sciences tracked the intellectual advancement of several hundred grad students in the sciences over four years. It studied how they developed crucial skills such as generating hypotheses, designing experiments, and analyzing data. To their surprise, these skills were closely related to the students’ engagement with their peers in the lab, and not so much with the guidance they received from faculty mentors.

Our brains evolved to think with people – to teach them, listen to them, argue with them, and exchange stories with them. This is the argument of the “social encoding advantage,” which says that the brain stores social information differently than it stores information that is non-social, causing us to remember it better.

So many of our experiences in school and at work treat thinking as the solitary manipulation of symbols inside our heads. We are asked to produce facts without a person to receive them. We make arguments without another person to debate. We are asked to learn without someone to teach, when research shows that we learn far better when we are preparing to teach someone.

The power of collaborative thinking is apparent in science, where fewer than 10% of journal articles in science and technology are authored by just one person. Nearly 70% of US patent applications now list more than one inventor, a number that has been steadily increasing for over 40 years.

The same is true in business. Brian Uzzi, a professor of management at Northwestern University, says: “[My research] suggests that the process of knowledge creation has fundamentally changed…almost everything that human beings do today, in terms of generation of value, is no longer done by individuals. It’s done by teams.”

The Value of Knowing What We Know

The idea of “extending” one’s mind may bring to mind images of radical hyperintelligence the likes of which humanity has never seen. But extended cognition is also about surfacing the knowledge we already have inside.

A series of studies has shown that experts are unable to fully articulate most of what they do and know. One study asked expert trauma surgeons to describe how they insert a shunt into the femoral artery – they neglected to cite nearly 70% of the actions they typically performed. 

Another study found that experimental psychologists omitted an average of 75% of the steps they took when designing experiments. And a study of expert computer programmers found they enumerated fewer than 50% of the tasks they carried out to debug a program.

By externalizing our knowledge, we not only free up our bandwidth and get smarter, we uncover the true value of the knowledge we already possess.

How Cognitive Extension Works In The Brain

Some of the most fascinating research presented by Paul in my opinion is about how the brain changes in response to the tools we use.

She cites a study indicating that when we grasp a tool, our “body schema” – our sense of our body’s shape, size, and position – expands to encompass the new tool. It is as if, from the perspective of our brain at least, that tool has now become an extension of our arm.

The more reliably these “mental extensions” – or tools – are available, the more deeply they become integrated into our thinking. 

Although the research so far has been done mainly on physical tools, I believe much the same findings apply to software tools. Think about how naturally and unthinkingly we perform a Google search to fill in a missing piece of information, or reach for our smartphone to text a friend.

If our mental map of the limits of our body can be so easily extended using tools, what happens when those tools extend almost infinitely through the Internet, around the world, and into the minds of countless people we’ve never met? 

Intelligence Is a Fluid Interaction Between Us And Our Environment

My main takeaway from The Extended Mind was a redefinition of intelligence.

Intelligence, according to the extended perspective, is not a stable property of the solid lump of gray matter encased in our skull. It is a “fluid transaction” between brains, bodies, spaces, relationships, and tools, all interacting together to leverage each medium’s unique capabilities.

With this in mind, Paul identifies a largely underappreciated aspect of education: the ability to orchestrate mental extensions skillfully. Instead of memorizing more, we should be taught to offload information, to externalize it to a medium that is best suited to it while freeing us to focus elsewhere.

Paul suggests that “Whenever possible, we should endeavor to transform information into an artifact, to make data into something real – and then proceed to interact with it, labeling it, mapping it, feeling it, tweaking it, showing it to others.”

When we consider the brain’s many shortcomings – its short attention span, difficulty focusing, porous memory – this presents an alternative path: to go around them. We shouldn’t try to “fix” an organ that has worked the same way for countless millennia. 

Instead, we should embrace the way our brains naturally work and begin to use the tools in our environment to unlock the full potential of our intelligence.

Software as the Ultimate Cognitive Extension

Paul addresses the use of technology only in passing in her book, but I think software actually incorporates each of the three kinds of externalized thinking she covers. 

Software (and the hardware it runs on) sometimes functions as an extension of our body, such as when we wear a smart watch or use gesture-based interfaces, thus tapping into many of the benefits of embodied cognition.

In other situations, software is more like an environment – a digital environment, of course – but I don’t think our minds make such a clear distinction, especially as virtual and augmented reality becomes ever higher fidelity. To the extent we inhabit the virtual spaces that software creates, and move within them, we are activating our situated cognition.

In many ways, it is the third form of intelligence identified by Paul that has long been the final frontier of technology: social intelligence. Homo sapiens survived the predators of the African savannah and even beat out stronger species of rival hominids through our ability to band together and share our skills and knowledge.

As Artificial Intelligence proliferates, we are beginning to relate to software as we relate to people. Conversing with AI-based chatbots draws on many of our social conventions and natural ways of communicating with other beings. Making conversations central to our relationship with technology gives that relationship some of the same fluidity and vibrancy we previously reserved for other humans.

Of the many ways we have extended our minds using technology for countless millennia, I believe we are on the cusp of creating a true “extended mind,” instantiating our memories, knowledge, and even intuition in ever more intelligent machines that surround us on all sides. 

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