What is the Extended Mind Thesis and why does it have the power to amplify our impact?

TL;DR your mind is not restricted to your skull.

Therefore, since your mind extends beyond your skull, you can legitimately “supersize” its performance not by going internal, but by going beyond the skull by shaping your body, your environment, ambient technology, and your relationships with other minds.

Now the story, context, evidence, and implications.

In 1996 a young philosopher of the mind, Andy Clark now a professor at the University of Edinburgh, along with his colleague David Chalmers, now a professor at NYU, published the paper The Extended Mind in which they explore the simple question: “Where does the mind stop and the rest of the world begin”. Their answer is surprising, and, I believe, correct.

Their words:

Consider three cases of human problem-solving:

(1) A person sits in front of a computer screen which displays images of various two-dimensional geometric shapes and is asked to answer questions concerning the potential fit of such shapes into depicted “sockets”. To assess fit, the person must mentally rotate the shapes to align them with the sockets.

(2) A person sits in front of a similar computer screen, but this time can choose either to physically rotate the image on the screen, by pressing a rotate button, or to mentally rotate the image as before. We can also suppose, not unrealistically, that some speed advantage accrues to the physical rotation operation.

(3) Sometime in the cyberpunk future, a person sits in front of a similar computer screen. This agent, however, has the benefit of a neural implant which can perform the rotation operation as fast as the computer in the previous example. The agent must still choose which internal resource to use (the implant or the good old fashioned mental rotation), as each resource makes different demands on attention and other concurrent brain activity.

How much cognition is present in these cases? We suggest that all three cases are similar. Case (3) with the neural implant seems clearly to be on a par with case (1). And case (2) with the rotation button displays the same sort of computational structure as case (3), although it is distributed across agent and computer instead of internalized within the agent. If the rotation in case (3) is cognitive, by what right do we count case (2) as fundamentally different? We cannot simply point to the skin/skull boundary as justification, since the legitimacy of that boundary is precisely what is at issue. But nothing else seems different.

The kind of case just described is by no means as exotic as it may at first appear. It is not just the presence of advanced external computing resources which raises the issue, but rather the general tendency of human reasoners to lean heavily on environmental supports. Thus consider the use of pen and paper to perform long multiplication (McClelland et al 1986, Clark 1989), the use of physical re-arrangements of letter tiles to prompt word recall in Scrabble (Kirsh 1995), the use of instruments such as the nautical slide rule (Hutchins 1995), and the general paraphernalia of language, books, diagrams, and culture. In all these cases the individual brain performs some operations, while others are delegated to manipulations of external media. Had our brains been different, this distribution of tasks would doubtless have varied.

In fact, even the mental rotation cases described in scenarios (1) and (2) are real. The cases reflect options available to players of the computer game Tetris. In Tetris, falling geometric shapes must be rapidly directed into an appropriate slot in an emerging structure. A rotation button can be used. David Kirsh and Paul Maglio (1994) calculate that the physical rotation of a shape through 90 degrees takes about 100 milliseconds, plus about 200 milliseconds to select the button. To achieve the same result by mental rotation takes about 1000 milliseconds. Kirsh and Maglio go on to present compelling evidence that physical rotation is used not just to position a shape ready to fit a slot, but often to help determine whether the shape and the slot are compatible. The latter use constitutes a case of what Kirsh and Maglio call an `epistemic action’. Epistemic actions alter the world so as to aid and augment cognitive processes such as recognition and search. Merely pragmatic actions, by contrast, alter the world because some physical change is desirable for its own sake (e.g., putting cement into a hole in a dam).

Epistemic action, we suggest, demands spread of epistemic credit. If, as we confront some task, a part of the world functions as a process which, were it done in the head, we would have no hesitation in recognizing as part of the cognitive process, then that part of the world is (so we claim) part of the cognitive process. Cognitive processes ain’t (all) in the head!

Let’s summarize the philosophy to crystalize the point → that pencil and paper long division we were all taught to do in grade school is actually thinking. We think with and on the paper, not simply use the paper to record our thoughts.

Seems so pedantic as to be laughably obvious.

Consider that Andy Clark was familiar with the work of Terry Winograd did in linguistics and early computer science. Terry’s book Understanding Computers and Cognition: A New Foundation for Design was a significant achievement in the field of Computational Theory of the Mind, the same field Clark worked in at the time. Terry was a pioneer in the field of programming computers to understand language. Terry’s book Language as a Cognitive Process, argues and aligns with Clark’s argument that language is an external cognition-enhancing artifact.

Why are we talking about Professor Winograd? He is relevant because he was the PhD advisor to two of his Stanford students, Sergey Brin and Larry Page, and whom he encouraged to work on search for, at the time, the brand-new world wide web. We now know their work as Google. Google it. As any person heading to an address they might not be familiar with, our smartphones have become seamlessly entrained in how we engage the world and think through things.

Extend with us.

The Clark and Chalmer paper and Google, Inc were launched on the world the same year.

And so, our minds can extend to our tools, loosely described. Our minds extend into our bodies. Interoception, our 8th sense, senses our internal state is currently a hot topic of investigation in neuroscience. It turns out our gut feelings are real and contain useful information.

Our minds even extend into our environment. Note the spatial cognition-based memorization techniques of the planet’s best memorizers. Our minds extend with others, look to the rich literature of mentors, partners, hunters and ranchers, pet-owners and coaches, old married couples, study groups, scientists and writers, parents and salespeople, teammates and co-creators. Jim Rohm famously said, “You are the average of the five people you spend the most time with.”

Our minds extend out from the skull so seamlessly and naturally, that it seems unremarkable, like that joke about the old fish asking two younger fish passing by “How’s the water?”

Now, some implications.

Legal- since the mind extends outward, encompassing the smartphone, is the theft of one, more like an assault than simple theft?

Insurance- since the mind extends outward, encompassing the environment, is the loss of a house due to fire or flood, equivalent to a bodily loss of limb or function, more than simple property?

Intellectual Property- since the mind extends outward, encompassing feedback, co-processing peers, which individual deserves credit for a solution or a work?

Environmental- since the mind extends outward, encompassing our surroundings, why isn’t eminent domain an action of bodily harm?

Social- since the mind extends outward, encompassing our close relationships, what would happen if we’d upgrade our peers? How much better could I think with better influences?

Health- since the mind extends into our body, encompassing our guts, how would we improve cognitively by getting good nutrition and plenty of fiber?

On and on…..

The mind extends beyond the skull, acting with and within its environment, looping outward inward, thinking with the situation it finds itself in, thinking with the tools it has.

Really want to “supersize” your mind? Improve your resources? Have a problem that's been resistant to solve? Consider going outside your skull and change something(s) with your body, your relationships, or your environments.

All of this is wonderfully understood by my son, sitting in the chair next to me while I'm typing this out…..counting on his fingers.



I write about elevating the underdog, the underappreciated, the overlooked @greensomefarms

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Kareem Royal Brantley

I write about elevating the underdog, the underappreciated, the overlooked @greensomefarms