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The Extended Mind |
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Andy Clark & David Chalmers [*] *[[Authors are listed in order of degree of belief
in the central thesis.]] |
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From: Analysis 58:10-23, 1998. Reprinted: The
Philosopher's Annual, vol XXI, 1998 |
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1 Introduction |
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Where does the mind
stop and the rest of the world begin? The question invites two standard
replies. Some accept the demarcations of skin and skull, and say that what is
outside the body is outside the mind. Others are impressed by arguments
suggesting that the meaning of our words "just ain't in the head",
and hold that this externalism about meaning carries over into an externalism
about mind. We propose to pursue a third position. We advocate a very
different sort of externalism: an active externalism, based on the
active role of the environment in driving cognitive processes. |
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2 Extended Cognition |
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Consider three cases of
human problem-solving: |
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(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. |
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(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. |
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(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. |
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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. |
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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. |
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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). |
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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! |
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3 Active Externalism |
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In these cases, the
human organism is linked with an external entity in a two-way interaction,
creating a coupled system that can be seen as a cognitive system in
its own right. All the components in the system play an active causal role,
and they jointly govern behavior in the same sort of way that cognition
usually does. If we remove the external component the system's behavioral
competence will drop, just as it would if we removed part of its brain. Our
thesis is that this sort of coupled process counts equally well as a
cognitive process, whether or not it is wholly in the head. |
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This externalism
differs greatly from standard variety advocated by Putnam (1975) and Burge
(1979). When I believe that water is wet and my twin believes that twin water
is wet, the external features responsible for the difference in our beliefs
are distal and historical, at the other end of a lengthy causal chain.
Features of the present are not relevant: if I happen to be surrounded
by XYZ right now (maybe I have teleported to Twin Earth), my beliefs still
concern standard water, because of my history. In these cases, the relevant
external features are passive. Because of their distal nature, they
play no role in driving the cognitive process in the here-and-now. This is
reflected by the fact that the actions performed by me and my twin are
physically indistinguishable, despite our external differences. |
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In the cases we
describe, by contrast, the relevant external features are active,
playing a crucial role in the here-and-now. Because they are coupled with the
human organism, they have a direct impact on the organism and on its
behavior. In these cases, the relevant parts of the world are in the loop,
not dangling at the other end of a long causal chain. Concentrating on this
sort of coupling leads us to an active externalism, as opposed to the
passive externalism of Putnam and Burge. |
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Many have complained
that even if Putnam and Burge are right about the externality of content, it
is not clear that these external aspects play a causal or explanatory role in
the generation of action. In counterfactual cases where internal structure is
held constant but these external features are changed, behavior looks just
the same; so internal structure seems to be doing the crucial work. We will
not adjudicate that issue here, but we note that active externalism is not
threatened by any such problem. The external features in a coupled system
play an ineliminable role - if we retain internal structure but change the
external features, behavior may change completely. The external features here
are just as causally relevant as typical internal features of the brain.[*] |
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*[[Much of the appeal
of externalism in the philosophy of mind may stem from the intuitive appeal
of active externalism. Externalists often make analogies involving external
features in coupled systems, and appeal to the arbitrariness of boundaries
between brain and environment. But these intuitions sit uneasily with the
letter of standard externalism. In most of the Putnam/Burge cases, the
immediate environment is irrelevant; only the historical environment counts.
Debate has focused on the question of whether mind must be in the head, but a
more relevant question in assessing these examples might be: is mind in the
present?]] |
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By embracing an active
externalism, we allow a more natural explanation of all sorts of actions. One
can explain my choice of words in Scrabble, for example, as the outcome of an
extended cognitive process involving the rearrangement of tiles on my tray.
Of course, one could always try to explain my action in terms of internal
processes and a long series of "inputs" and "actions",
but this explanation would be needlessly complex. If an isomorphic process
were going on in the head, we would feel no urge to characterize it in this
cumbersome way.[*] In a very real sense, the re-arrangement of tiles on the
tray is not part of action; it is part of thought. |
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*[[Herbert Simon (1981)
once suggested that we view internal memory as, in effect, an external
resource upon which "real" inner processes operate. "Search in
memory," he comments, "is not very different from search of the
external environment." Simon's view at least has the virtue of treating
internal and external processing with the parity they deserve, but we suspect
that on his view the mind will shrink too small for most people's tastes. ]] |
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The view we advocate
here is reflected by a growing body of research in cognitive science. In
areas as diverse as the theory of situated cognition (Suchman 1987), studies
of real-world-robotics (Beer 1989), dynamical approaches to child development
(Thelen and Smith 1994), and research on the cognitive properties of
collectives of agents (Hutchins 1995), cognition is often taken to be
continuous with processes in the environment.[*] Thus, in seeing cognition as
extended one is not merely making a terminological decision; it makes a
significant difference to the methodology of scientific investigation. In
effect, explanatory methods that might once have been thought appropriate
only for the analysis of "inner" processes are now being adapted
for the study of the outer, and there is promise that our understanding of
cognition will become richer for it. |
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*[Philosophical views
of a similar spirit can be found in Haugeland 1995, McClamrock 1985, Varela
et al 1991, and Wilson 1994.] |
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Some find this sort of
externalism unpalatable. One reason may be that many identify the cognitive
with the conscious, and it seems far from plausible that consciousness
extends outside the head in these cases. But not every cognitive process, at
least on standard usage, is a conscious process. It is widely accepted that
all sorts of processes beyond the borders of consciousness play a crucial
role in cognitive processing: in the retrieval of memories, linguistic
processes, and skill acquisition, for example. So the mere fact that external
processes are external where consciousness is internal is no reason to deny
that those processes are cognitive. |
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More interestingly, one
might argue that what keeps real cognition processes in the head is the
requirement that cognitive processes be portable. Here, we are moved
by a vision of what might be called the Naked Mind: a package of resources
and operations we can always bring to bear on a cognitive task, regardless of
the local environment. On this view, the trouble with coupled systems is that
they are too easily decoupled. The true cognitive processes are those
that lie at the constant core of the system; anything else is an add-on
extra. |
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There is something to
this objection. The brain (or brain and body) comprises a package of basic,
portable, cognitive resources that is of interest in its own right. These
resources may incorporate bodily actions into cognitive processes, as when we
use our fingers as working memory in a tricky calculation, but they will not
encompass the more contingent aspects of our external environment, such as a
pocket calculator. Still, mere contingency of coupling does not rule out
cognitive status. In the distant future we may be able to plug various
modules into our brain to help us out: a module for extra short-term memory
when we need it, for example. When a module is plugged in, the processes
involving it are just as cognitive as if they had been there all along.[*] |
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*[[Or consider the
following passage from a recent science fiction novel (McHugh 1992, p. 213):
"I am taken to the system's department where I am attuned to the system.
All I do is jack in and then a technician instructs the system to attune and
it does. I jack out and query the time. 10:52. The information pops up.
Always before I could only access information when I was jacked in, it gave
me a sense that I knew what I thought and what the system told me, but now,
how do I know what is system and what is Zhang?"]] |
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Even if one were to
make the portability criterion pivotal, active externalism would not be
undermined. Counting on our fingers has already been let in the door, for
example, and it is easy to push things further. Think of the old image of the
engineer with a slide rule hanging from his belt wherever he goes. What if
people always carried a pocket calculator, or had them implanted? The real
moral of the portability intuition is that for coupled systems to be relevant
to the core of cognition, reliable coupling is required. It happens
that most reliable coupling takes place within the brain, but there can
easily be reliable coupling with the environment as well. If the resources of
my calculator or my Filofax are always there when I need them, then they are
coupled with me as reliably as we need. In effect, they are part of the basic
package of cognitive resources that I bring to bear on the everyday world.
These systems cannot be impugned simply on the basis of the danger of
discrete damage, loss, or malfunction, or because of any occasional
decoupling: the biological brain is in similar danger, and occasionally loses
capacities temporarily in episodes of sleep, intoxication, and emotion. If
the relevant capacities are generally there when they are required, this is
coupling enough. |
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Moreover, it may be
that the biological brain has in fact evolved and matured in ways which
factor in the reliable presence of a manipulable external environment. It
certainly seems that evolution has favored on-board capacities which are
especially geared to parasitizing the local environment so as to reduce
memory load, and even to transform the nature of the computational problems
themselves. Our visual systems have evolved to rely on their environment in
various ways: they exploit contingent facts about the structure of natural
scenes (e.g. Ullman and Richards 1984), for example, and they take advantage
of the computational shortcuts afforded by bodily motion and locomotion (e.g.
Blake and Yuille, 1992). Perhaps there are other cases where evolution has
found it advantageous to exploit the possibility of the environment being in
the cognitive loop. If so, then external coupling is part of the truly basic
package of cognitive resources that we bring to bear on the world. |
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Language may be an
example. Language appears to be a central means by which cognitive processes
are extended into the world. Think of a group of people brainstorming around
a table, or a philosopher who thinks best by writing, developing her ideas as
she goes. It may be that language evolved, in part, to enable such extensions
of our cognitive resources within actively coupled systems. |
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Within the lifetime of
an organism, too, individual learning may have molded the brain in ways that
rely on cognitive extensions that surrounded us as we learned. Language is
again a central example here, as are the various physical and computational
artifacts that are routinely used as cognitive extensions by children in
schools and by trainees in numerous professions. In such cases the brain
develops in a way that complements the external structures, and learns to
play its role within a unified, densely coupled system. Once we recognize the
crucial role of the environment in constraining the evolution and development
of cognition, we see that extended cognition is a core cognitive process, not
an add-on extra. |
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An analogy may be
helpful. The extraordinary efficiency of the fish as a swimming device is
partly due, it now seems, to an evolved capacity to couple its swimming
behaviors to the pools of external kinetic energy found as swirls, eddies and
vortices in its watery environment (see Triantafyllou and G. Triantafyllou
1995). These vortices include both naturally occurring ones (e.g., where
water hits a rock) and self-induced ones (created by well-timed tail flaps).
The fish swims by building these externally occurring processes into the very
heart of its locomotion routines. The fish and surrounding vortices together
constitute a unified and remarkably efficient swimming machine. |
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Now consider a reliable
feature of the human environment, such as the sea of words. This linguistic
surround envelopes us from birth. Under such conditions, the plastic human
brain will surely come to treat such structures as a reliable resource to be
factored into the shaping of on-board cognitive routines. Where the fish
flaps its tail to set up the eddies and vortices it subsequently exploits, we
intervene in multiple linguistic media, creating local structures and
disturbances whose reliable presence drives our ongoing internal processes.
Words and external symbols are thus paramount among the cognitive vortices
which help constitute human thought. |
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4 From Cognition to Mind |
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So far we have spoken
largely about "cognitive processing", and argued for its extension
into the environment. Some might think that the conclusion has been bought
too cheaply. Perhaps some processing takes place in the environment,
but what of mind? Everything we have said so far is compatible with
the view that truly mental states - experiences, beliefs, desires, emotions,
and so on - are all determined by states of the brain. Perhaps what is truly
mental is internal, after all? |
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We propose to take
things a step further. While some mental states, such as experiences, may be
determined internally, there are other cases in which external factors make a
significant contribution. In particular, we will argue that beliefs
can be constituted partly by features of the environment, when those features
play the right sort of role in driving cognitive processes. If so, the mind
extends into the world. |
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First, consider a
normal case of belief embedded in memory. Inga hears from a friend that there
is an exhibition at the |
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Now consider Otto. Otto
suffers from Alzheimer's disease, and like many Alzheimer's patients, he
relies on information in the environment to help structure his life. Otto
carries a notebook around with him everywhere he goes. When he learns new
information, he writes it down. When he needs some old information, he looks
it up. For Otto, his notebook plays the role usually played by a biological
memory. Today, Otto hears about the exhibition at the |
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Clearly, Otto walked to
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The alternative is to
say that Otto has no belief about the matter until he consults his notebook;
at best, he believes that the museum is located at the address in the
notebook. But if we follow Otto around for a while, we will see how unnatural
this way of speaking is. Otto is constantly using his notebook as a matter of
course. It is central to his actions in all sorts of contexts, in the way
that an ordinary memory is central in an ordinary life. The same information
might come up again and again, perhaps being slightly modified on occasion,
before retreating into the recesses of his artificial memory. To say that the
beliefs disappear when the notebook is filed away seems to miss the big
picture in just the same way as saying that Inga's beliefs disappear as soon
as she is no longer conscious of them. In both cases the information is reliably
there when needed, available to consciousness and available to guide action,
in just the way that we expect a belief to be. |
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Certainly, insofar as
beliefs and desires are characterized by their explanatory roles, Otto's and
Inga's cases seem to be on a par: the essential causal dynamics of the two
cases mirror each other precisely. We are happy to explain Inga's action in
terms of her occurrent desire to go to the museum and her standing belief
that the museum is on |
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If this is right, we
can even construct the case of Twin Otto, who is just like Otto except that a
while ago he mistakenly wrote in his notebook that the |
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This mirrors the
conclusion of Putnam and Burge, but again there are important differences. In
the Putnam/Burge cases, the external features constituting differences in
belief are distal and historical, so that twins in these cases produce
physically indistinguishable behavior. In the cases we are describing, the
relevant external features play an active role in the here-and-now, and have
a direct impact on behavior. Where Otto walks to |
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*[[In the terminology
of Chalmers' "The Components of Content" (forthcoming): the twins
in the Putnam and Burge cases differ only in their relational content,
but Otto and his twin can be seen to differ in their notional content,
which is the sort of content that governs cognition. Notional content is
generally internal to a cognitive system, but in this case the cognitive
system is itself effectively extended to include the notebook.]] |
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The moral is that when
it comes to belief, there is nothing sacred about skull and skin. What makes
some information count as a belief is the role it plays, and there is no
reason why the relevant role can be played only from inside the body. |
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Some will resist this
conclusion. An opponent might put her foot down and insist that as she uses
the term "belief", or perhaps even according to standard usage,
Otto simply does not qualify as believing that the museum is on |
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To provide substantial
resistance, an opponent has to show that Otto's and Inga's cases differ in
some important and relevant respect. But in what deep respect are the cases
different? To make the case solely on the grounds that information is
in the head in one case but not in the other would be to beg the question. If
this difference is relevant to a difference in belief, it is surely not primitively
relevant. To justify the different treatment, we must find some more basic
underlying difference between the two. |
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It might be suggested
that the cases are relevantly different in that Inga has more reliable
access to the information. After all, someone might take away Otto's notebook
at any time, but Inga's memory is safer. It is not implausible that constancy
is relevant: indeed, the fact that Otto always uses his notebook played some
role in our justifying its cognitive status. If Otto were consulting a
guidebook as a one-off, we would be much less likely to ascribe him a
standing belief. But in the original case, Otto's access to the notebook is
very reliable - not perfectly reliable, to be sure, but then neither is
Inga's access to her memory. A surgeon might tamper with her brain, or more
mundanely, she might have too much to drink. The mere possibility of such
tampering is not enough to deny her the belief. |
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One might worry that
Otto's access to his notebook in fact comes and goes. He showers
without the notebook, for example, and he cannot read it when it is dark.
Surely his belief cannot come and go so easily? We could get around this
problem by redescribing the situation, but in any case an occasional
temporary disconnection does not threaten our claim. After all, when Inga is
asleep, or when she is intoxicated, we do not say that her belief disappears.
What really counts is that the information is easily available when the
subject needs it, and this constraint is satisfied equally in the two cases.
If Otto's notebook were often unavailable to him at times when the
information in it would be useful, there might be a problem, as the
information would not be able to play the action-guiding role that is central
to belief; but if it is easily available in most relevant situations, the
belief is not endangered. |
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Perhaps a difference is
that Inga has better access to the information than Otto does? Inga's
"central" processes and her memory probably have a relatively
high-bandwidth link between them, compared to the low-grade connection
between Otto and his notebook. But this alone does not make a difference
between believing and not believing. Consider Inga's museum-going friend
Lucy, whose biological memory has only a low-grade link to her central
systems, due to nonstandard biology or past misadventures. Processing in
Lucy's case might be less efficient, but as long as the relevant information
is accessible, Lucy clearly believes that the museum is on |
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Another suggestion
could be that Otto has access to the relevant information only by perception,
whereas Inga has more direct access -- by introspection, perhaps. In some
ways, however, to put things this way is to beg the question. After all, we
are in effect advocating a point of view on which Otto's internal processes
and his notebook constitute a single cognitive system. From the standpoint of
this system, the flow of information between notebook and brain is not
perceptual at all; it does not involve the impact of something outside the
system. It is more akin to information flow within the brain. The only deep
way in which the access is perceptual is that in Otto's case, there is a
distinctly perceptual phenomenology associated with the retrieval of the
information, whereas in Inga's case there is not. But why should the nature
of an associated phenomenology make a difference to the status of a belief?
Inga's memory may have some associated phenomenology, but it is still a
belief. The phenomenology is not visual, to be sure. But for visual
phenomenology consider the Terminator, from the Arnold Schwarzenegger movie
of the same name. When he recalls some information from memory, it is
"displayed" before him in his visual field (presumably he is
conscious of it, as there are frequent shots depicting his point of view).
The fact that standing memories are recalled in this unusual way surely makes
little difference to their status as standing beliefs. |
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These various small
differences between Otto's and Inga's cases are all shallow
differences. To focus on them would be to miss the way in which for Otto,
notebook entries play just the sort of role that beliefs play in guiding most
people's lives. |
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Perhaps the intuition
that Otto's is not a true belief comes from a residual feeling that the only
true beliefs are occurrent beliefs. If we take this feeling seriously, Inga's
belief will be ruled out too, as will many beliefs that we attribute in
everyday life. This would be an extreme view, but it may be the most
consistent way to deny Otto's belief. Upon even a slightly less extreme view
- the view that a belief must be available for consciousness, for
example - Otto's notebook entry seems to qualify just as well as Inga's
memory. Once dispositional beliefs are let in the door, it is difficult to
resist the conclusion that Otto's notebook has all the relevant dispositions.
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5 Beyond the Outer Limits |
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If the thesis is
accepted, how far should we go? All sorts of puzzle cases spring to mind.
What of the amnesic villagers in 100 Years of Solitude, who forget the
names for everything and so hang labels everywhere? Does the information in
my Filofax count as part of my memory? If Otto's notebook has been tampered
with, does he believe the newly-installed information? Do I believe the
contents of the page in front of me before I read it? Is my cognitive state
somehow spread across the Internet? |
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We do not think that
there are categorical answers to all of these questions, and we will not give
them. But to help understand what is involved in ascriptions of extended
belief, we can at least examine the features of our central case that make
the notion so clearly applicable there. First, the notebook is a constant in
Otto's life - in cases where the information in the notebook would be
relevant, he will rarely take action without consulting it. Second, the
information in the notebook is directly available without difficulty. Third,
upon retrieving information from the notebook he automatically endorses it.
Fourth, the information in the notebook has been consciously endorsed at some
point in the past, and indeed is there as a consequence of this
endorsement.[*] The status of the fourth feature as a criterion for belief is
arguable (perhaps one can acquire beliefs through subliminal perception, or
through memory tampering?), but the first three features certainly play a
crucial role. |
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*[[The constancy and
past-endorsement criteria may suggest that history is partly constitutive of
belief. One might react to this by removing any historical component (giving
a purely dispositional reading of the constancy criterion and eliminating the
past-endorsement criterion, for example), or one might allow such a component
as long as the main burden is carried by features of the present.]] |
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Insofar as increasingly
exotic puzzle cases lack these features, the applicability of the notion of
"belief" gradually falls off. If I rarely take relevant action
without consulting my Filofax, for example, its status within my cognitive
system will resemble that of the notebook in Otto's. But if I often act
without consultation - for example, if I sometimes answer relevant questions
with "I don't know" - then information in it counts less clearly as
part of my belief system. The Internet is likely to fail on multiple counts,
unless I am unusually computer-reliant, facile with the technology, and
trusting, but information in certain files on my computer may qualify. In
intermediate cases, the question of whether a belief is present may be
indeterminate, or the answer may depend on the varying standards that are at
play in various contexts in which the question might be asked. But any
indeterminacy here does not mean that in the central cases, the answer is not
clear. |
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What about socially
extended cognition? Could my mental states be partly constituted by the
states of other thinkers? We see no reason why not, in principle. In an
unusually interdependent couple, it is entirely possible that one partner's
beliefs will play the same sort of role for the other as the notebook plays
for Otto.[*] What is central is a high degree of trust, reliance, and
accessibility. In other social relationships these criteria may not be so
clearly fulfilled, but they might nevertheless be fulfilled in specific
domains. For example, the waiter at my favorite restaurant might act as a
repository of my beliefs about my favorite meals (this might even be
construed as a case of extended desire). In other cases, one's beliefs might
be embodied in one's secretary, one's accountant, or one's collaborator.[*] |
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*[[From the New York
Times, March 30, 1995, p.B7, in an article on former UCLA basketball
coach John Wooden: "Wooden and his wife attended 36 straight Final
Fours, and she invariably served as his memory bank. Nell Wooden rarely
forgot a name - her husband rarely remembered one - and in the
standing-room-only Final Four lobbies, she would recognize people for
him."]] |
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*[[Might this sort of
reasoning also allow something like Burge's extended "arthritis"
beliefs? After all, I might always defer to my doctor in taking relevant
actions concerning my disease. Perhaps so, but there are some clear
differences. For example, any extended beliefs would be grounded in an
existing active relationship with the doctor, rather than in a historical
relationship to a language community. And on the current analysis, my
deference to the doctor would tend to yield something like a true belief that
I have some other disease in my thigh, rather than the false belief that I
have arthritis there. On the other hand, if I used medical experts solely as
terminological consultants, the results of Burge's analysis might be
mirrored.]] |
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In each of these cases,
the major burden of the coupling between agents is carried by language.
Without language, we might be much more akin to discrete Cartesian
"inner" minds, in which high-level cognition relies largely on
internal resources. But the advent of language has allowed us to spread this
burden into the world. Language, thus construed, is not a mirror of our inner
states but a complement to them. It serves as a tool whose role is to extend
cognition in ways that on-board devices cannot. Indeed, it may be that the
intellectual explosion in recent evolutionary time is due as much to this
linguistically-enabled extension of cognition as to any independent
development in our inner cognitive resources. |
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What, finally, of the
self? Does the extended mind imply an extended self? It seems so. Most of us
already accept that the self outstrips the boundaries of consciousness; my
dispositional beliefs, for example, constitute in some deep sense part of who
I am. If so, then these boundaries may also fall beyond the skin. The
information in Otto's notebook, for example, is a central part of his
identity as a cognitive agent. What this comes to is that Otto himself
is best regarded as an extended system, a coupling of biological organism and
external resources. To consistently resist this conclusion, we would have to
shrink the self into a mere bundle of occurrent states, severely threatening
its deep psychological continuity. Far better to take the broader view, and
see agents themselves as spread into the world. |
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As with any
reconception of ourselves, this view will have significant consequences.
There are obvious consequences for philosophical views of the mind and for
the methodology of research in cognitive science, but there will also be
effects in the moral and social domains. It may be, for example, that in some
cases interfering with someone's environment will have the same moral
significance as interfering with their person. And if the view is taken
seriously, certain forms of social activity might be reconceived as less akin
to communication and action, and as more akin to thought. In any case, once
the hegemony of skin and skull is usurped, we may be able to see ourselves
more truly as creatures of the world. |
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|
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Article on-line at: http://consc.net/papers/extended.html |
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