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PH1102E

Week 10

The extended mind

I. The extended mind hypothesis

II. Arguments for extended cognition

III. Taking stock

IV. A contracted mind?

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I. The extended mind hypothesis

Using a pocket calculator, I can figure out what 438 times 762 is in less than a second. Working it out on

paper takes around 30 seconds. Figuring it out in my head takes more than a minute.

What should we conclude from these observations?

One possible conclusion is that if I use only my own mind, I arrive at the answer more slowly than if I

enlist the help of paper and pencil or pocket calculator. Of course my mind is somehow involved in every

case. In the first case, it is my mind that decides which buttons to press, and in which order:

and it is also my mind that forms the belief that the numerals that subsequently appear on the

calculator’s screen represent the product of 438 and 762. In the second case, my mind decides to smear

graphite onto paper in the following pattern:

438

762

and then thinks that 8 times 2 is sixteen, and decides to smear more graphite as follows:

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438

762

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and so forth.

But in the third case, where I solve the problem with my eyes closed, my mind must actually do the

whole calculation, instead of merely deciding which buttons to press, or deciding which single-digit

multiplications to perform, which numerals to carry, etc.

On this way of viewing things, someone who can do the multiplication in his head has a cognitive ability

that someone who cannot do it in his head, but only on paper, or only with a calculator, lacks.

But there is another way of viewing things. According to this alternative point of view, there is no

cognitive difference between someone who can do long multiplication in his head and someone who

can do it only using a calculator, provided that the latter person actually has a calculator at his disposal.

The fact that I can come up with the product of 438 and 762 more quickly with a calculator than without

one does not show that it takes me longer to come up with the answer using only my own mind than

using both my mind and a calculator. It shows that I can come up with the answer more quickly when

my mind has a pocket calculator as one of its parts.

This is how Clark and Chalmers view things. They think it is a mistake to think that less thought takes

place when someone does long multiplication using a calculator than when someone does the same

multiplication in his head. In their opinion, at least as much thought takes place in the former case as in

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the latter. Using a calculator is not a way to avoid thinking. It is a way to think in an extended part of

your mind: a part of your mind that exists outside of your natural, biological body. The same mental

activity takes place in you when you multiply with a calculator as when you multiply in your head. It’s

just that a large part of that mental activity takes place in a part of your mind that exists outside of your

skull. It takes place in a part of your mind that looks like this:

The idea that the calculator is not just a mental-labor-saving device, but an actual locus of cognitive

activity, is typical of “active externalism,” defined by the so-called extended mind hypothesis:

Extended Mind Hypothesis: many of our cognitive states, processes, etc. occur outside of our bodies.

According to Clark and Chalmers, calculating with a calculator is just one example of extra-bodily

cognition. They think that human beings are capable of all kinds of extended cognition, including

extended memory, desire, and language comprehension. Very often, what we would normally describe

as a situation in which a person makes use of some external prop to make up for a cognitive deficit,

Clark and Chalmers want to describe as a situation in which the person has extended his mind to include

a part of his environment in which he can now perform cognitive tasks that he could not perform

before.

II. Arguments for extended cognition

Clark and Chalmers offer a number of arguments for the existence of extended cognition (cognitive

processes that occur outside of our bodies), but all of these have the same basic format:

E1. If some process that occurs outside of a person’s body would be considered part of that person’s

cognitive life if it occurred inside his body, then that process is part of that person’s cognitive life.

E2. ________ is a process that occurs outside of a person’s body, and that we would consider to be

part of that person’s cognitive life it it occurred inside his body.

E3. Therefore, ________ is a part of that person’s cognitive life that occurs outside of his body; i.e.,

_______ is an example of extended cognition.

The Otto/Inga argument is of this form. Otto, who suffers from Alzheimer’s Disease, carries around a

notebook in which he has written down all kinds of useful information that his ailing brain is no longer

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able to retain. He keeps the notebook handy at all times, and consults it in the same situations in which

the healthy Inga consults her native memory. We can imagine that Otto’s notebook plays essentially the

same role in his life as Inga’s memory plays in hers.

The point is not that Otto’s relationship to his notebook is in all respects identical to Inga's relationship

to her memory. Otto accesses the information in his notebook through optical channels, while Inga

accesses the information in her memory electrochemically; the notebook is made of paper and ink,

while Inga’s memory centers are made of protein; etc. The point is just that the notebook’s role in Otto’s

life duplicates the role of Inga’s memory in her life in all cognitively relevant respects. Given that this is

so, and given that Inga’s memory is part of her cognitive life, it follows (from the first premise of the

argument outlined above) that Otto’s notebook is part of his cognitive life. It is a part of his cognitive life

in exactly the same way that Inga’s ordinary, natural memory is part of her cognitive life.

To get arguments for other forms of extended cognition, we need only identify other external

phenomena that play the same roles as corresponding neural phenomena which we generally count as

cognitive. The calculator is one example that we’ve already considered: if I were to do in my head what I

do with a pocket-calculator, we’d consider what I was doing to be cognitive activity; so (again from E1),

when I use a calculator, I am doing mental math. It’s just that I’m doing it (partly) in the calculator,

rather than in my brain.

For another example, consider the service that an interpreter provides to his or her client. As it happens,

I do not speak or understand Russian at all. But suppose that I were extremely wealthy, and, for some

reason, planned to spend a lot of time in Russia. Being a sort of lazy person, instead of learning Russian, I

hire a full-time interpreter who follows me wherever I go, and, when necessary, translates other

people’s Russian into fluent English for me, and my English into fluent Russian for them.

By hiring this interpreter and keeping him with me at all times, do I gain the ability to speak and

understand Russian? It seems that I do, if Clark and Chalmers are correct. True, I don’t get to understand

Russian conversation in real time -- I have to wait for my interpreter to translate the sentences into

English. But if my interpreter is very good, the time delay could be very small; and, after all, there could

be Russians who are a bit slow, and take a while to understand what people say to them in Russian too.

My interpreter could die, or abandon me. But if I hire several backup interpreters in anticipation of this

possibility, the odds of my being left interpreterless might be no greater than the odds of an ordinary

Russian having a stroke that destroys the language centers of his brain. Etc.1

So it seems that we can imagine a situation in which an interpreter (or team of interpreters) plays

essentially the same role in my life as an ordinary Russian speaker’s neural language centers play in his.

Given that we count what’s going on in a Russian’s brain when she comprehends Russian as one of her

cognitive processes, we must, by E1, count what goes on in my interpreter’s brain as one of my cognitive

processes. (So this would be a case in which a single process counts as a cognitive process of two

people: me, and my interpreter.)

1 We could also imagine that translation software becomes so good that I can wear a small hearing-aid type device

that converts Russian into English in real time.

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III. Taking stock

The extended mind hypothesis says that, some, and perhaps many, of your cognitive processes occur at

least partly outside of your body.

Whether the hypothesis is true depends on what is meant by “body.”

In one sense, my body is just my skin and its contents (or, if you want to be slightly more sophisticated

about it: the cluster of cells that trace their origins back to the zygote from which I developed). A

modest amount of imagination tells us that there is no principled obstacle to removing my brain from

my skull while maintaining its channels of communication with the rest of my body by means of high-

bandwidth wires, fiber-optic cables, or wireless telecommunication paraphernalia. We could then

gradually replace the cells in my remotely-located brain with functionally equivalent computer

components, until we are left with a powerful computer that duplicates the input-output architecture of

my brain, and that communicates with my spinal cord, optical nerves, etc. by Wi-Fi. Voilà: extended

cognition.

On the other hand, we might define a person’s “body” as the place where his or her cognition takes

place. In that case, extended cognition is impossible by definition.

The extended mind hypothesis would therefore seem to be either trivially false (given the second

definition of “body”) or philosophically uninteresting (given the first definition). Even so, the debate

surrounding the extended mind hypothesis raises some interesting questions. These are not questions

about the spatial boundaries of the mind, however, but about its conceptual boundaries. To see what

these questions are, we need to take a more critical look at Clark’s and Chalmers’ arguments for

extended cognition.

IV. A contracted mind?

As we have seen, the argument for extended cognition rests on two claims. The first is that we should

not apply a double-standard to intra- and extra- cranial processes: if two processes perform equal

functions, we cannot say that one of them, but not the other, counts as part of cognition, just because

one but not the other other occurs inside someone’s head. The second claim is that to avoid the double-

standard, we must recognize various extra-cranial processes as cognitive processes.

Suppose it comes to light that the female employees of a company are paid less than their male

counterparts, despite doing the same work as the men, equally well. This is a clear case of a double-

standard. We could eliminate the double-standard by paying the women more. But we could also

eliminate it by paying the men less.

Similarly, when it comes to cognitive status, there are two ways to avoid a double-standard for

functionally equivalent intra- and extra-cranial processes. We could avoid the double-standard by

counting both processes as cognitive. This is the solution that Clark and Chalmers favor. Alternatively,

we could avoid the double-standard by counting neither process as cognitive. Why shouldn’t we take

this approach instead?

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Clark and Chalmers argue that Otto’s notebook is an integral part of Otto's cognitive life, since it

functions just like Inga’s memory. The notebook simply is memory, realized externally in paper and ink.

But one could also argue that Inga’s memory is not an integral part of her cognitive life, since it functions

just like Otto’s notebook. Inga’s memory is nothing but a notebook that she carries around in her head.

Both positions avoid the double-standard. How do we decide between them?

In some ways, it doesn’t matter. Consider the case of poor Gustav, who has neither teeth nor dental

insurance. Fortunately, he does have a battery-powered blender. With this, he can eat almost anything

he wants, albeit in pabulum form. In any situation in which Inga would deploy her teeth, Gustav deploys

his blender. Dentally speaking, the blender plays the same role in Gustav’s life as Inga’s teeth play in

hers.

Is this a case for extended dentition? Well, you can say what you like. We don’t care what the answer is,

because our teeth do not play an existentially central role in our lives. Much as we would miss them, we

could survive the loss of our teeth.

This last consideration suggests a method for deciding how to resolve the double-standard that Clark

and Chalmers rightly identify as unsustainable (i.e., whether we should resolve it by way of extension, or

by way of contraction). The aspects of cognition that are most important to us are those whose loss we

do not consider survivable. These aspects of cognition, I suggest, are mental in the most central

psychological sense in of the word. (Of course, if a cognitive process is accompanied by phenomenal

consciousness, it can be said to be “mental” in the equally central sense of being accompanied by

phenomenal consciousness.)

Consider Victor, who is incapable of performing any save the simplest of arithmetical calculations. Single

digit addition and subtraction are his limit. He has the concepts of addition, subtraction, multiplication

and division, and can tell when he is confronted with a task that requires a specific form of arithmetical

reckoning. He just can’t carry out the computations. This being so, Victor always carries a pocket

calculator, which he uses in any situation in which an ordinary person (like Inga) would perform a

computation in her head.

Does mental reckoning occur in Victor’s calculator? According to those who would extend the mind, it

does. Certainly we could describe the case in such a way that Victor’s calculator plays essentially the

same role in his life as the neural basis of Inga’s arithmetical prowess plays in hers. If we are to count

what Inga does when she calculates in her head as a mental process, then we must equally count what

happens in Victor’s calculator as a mental process (or an integral part thereof). By the same token, if we

do not count the operations of the calculator as instances of cognition, then we should not count Inga’s

calculations as part of cognition.

Which way should we jump in this case? If survivability of loss is to be our guide, it seems clear that we

should go the way of contraction. Losing one’s ability to do simple arithmetic would be annoying and

inconvenient (although far less so today than before the advent of the pocket calculator), but it is clearly

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something that one could survive. This is proven by the fact that Victor could survive the loss of his

calculator.

How about memory? Could a person survive the loss of that? As we know from our study of personal

identity, opinions about this differ, but it seems to me that he could (recall that this was also the opinion

of Dainton and Bayne).

Those who consider memory to be one of a person’s defining characteristics might be inclined to side

with Clark and Chalmers, but caution is in order here. Suppose Inga were to lose her memory entirely.

Perhaps this loss would result in the non-existence of Inga. But if memory is all that is lost, then surely

some cognitive agent would remain, albeit a severely impaired one. There would be a clear sense in

which a cognitive system would survive the memory loss, even if Inga as a person did not.

Is the survivability test for cognitive status a reasonable one? Here is a possible basis for thinking that it

is not: it could be that a cognitive system comprises processes or capacities any one of which the system

could survive without. In that case, the survivability test would compel us to say that no process or

capacity counts as cognitive, since you (or at rate the cognitive system that you include) could survive

the loss of any single process or capacity!

But it seems to me that there are certain processes whose losses a cognitive system could not survive.

For example, consider occurrent judgement or “mental assent.” Insofar as he is a cognitive system, Otto

could survive the loss of his notebook, and insofar as she is a cognitive system, Inga could survive the

loss of her memory. But could Otto and Inga survive the loss of their ability to give mental assent to

representations derived from memory and sensation? I can conceive of a mind with no memory, but can

I conceive of a mind with no capacity for judgement -- no capacity for accepting information as accurate

or inaccurate, true or false?

Perhaps; but then the mind of which I am conceiving does not appear to be capable of anything that

could really be called “cognition.” Maybe it would be capable of raw appetition (although this is not

clear), and so capable of “cognition” in an broad sense of this word which covers not only thinking and

problem solving, but also desiring, wishing, and lusting. In that case, it seems that the right thing to say

would be that a cognitive system is essentially a combination of two capacities: a capacity for making

judgements, and a capacity for having desires. Maybe a cognitive system could survive the loss of one of

these capacities, but it is hard to see how it could survive the loss of both.

Similar comments apply to Victor. Against Clark and Chalmers, one could argue that the genuinely

thoughtful part of mathematical reasoning lies not in the computations one performs, but in recognizing

a computational problem as such, framing the problem in a way that makes it amenable to

computation, and applying the results of the computation. These are clear-cut cases of occurrent

judgement. Viewed in this light, the function of mental reckoning, like that of memory, is to supply grist

to the cognitive mill.

For all of the philosophical debate surrounding it, the extended mind hypothesis should not be

considered philosophically controversial. The interesting hypothesis in this neighborhood relates to the

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conceptual rather than spatial boundaries of cognition. The intriguing possibility is not that we can think

outside our skulls: it is that much of what we unreflectively count as thought is really no more than a

crutch for or input to thought. When it comes to this possibility, the question is not one of where we

are, but what.

M.W.P.