I've always liked the idea, lucidly presented by Andy Clark over many years, that our minds are impossible to distinguish from our environment, because they really can't exist in the absence of a cognitive coupling between the two. I am relaying below the entire text of an instructive and interesting book review by Erik Myin of a book of commentaries on an influential 1998 paper by Andy Clark and David Chalmers titled "The extended mind." (very much worth reading, PDF here).
Where is the mind? "In the head" or "in the brain," most people might respond. The philosopher Gilbert Ryle gave a different answer:
The statement "the mind is in its own place," as theorists might construe it, is not true, for the mind is not even a metaphorical "place." On the contrary, the chessboard, the platform, the scholar's desk, the judge's bench, the lorry, the driver's seat, the studio and the football field are among its places. (1)
Recently, this idea of the mind not being confined to the head has been reinvigorated by philosophers and cognitive scientists, who see the mind as "spreading out" or "extending" into the world. "How do you know the way to San José?" philosopher John Haugeland has famously asked (2). Chances are you don't have some inner analog of a printed map. Rather, you know where you should enter the highway, and then you get there by following the road signs. Your knowledge seems to be partially "implemented" in the environment. There is now a blooming field of research into "situation cognition," which explores how cognitive or mental phenomena such as problem solving or remembering can be strongly dependent on interactions between subjects and their environments.
The possible far-reaching implications of a situated view of cognition were brought into sharp focus by Andy Clark and David Chalmers in their 1998 paper "The extended mind" (3). There they defend the idea that the mind "extends" into the environment in cases in which a human organism and the environment become cognitively coupled systems. Their by now iconic illustration of cognitive coupling involves "Otto," a "slightly amnesic" person, who uses a notebook to write down important facts that he is otherwise likely to forget. Unlike a person who remembers the address of the Museum of Modern Art by relying on natural memory, Otto recalls it by accessing his notebook. If one supposes that the notebook is constantly available to Otto and that what is written in it is endorsed by Otto, it becomes plausible—so Clark and Chalmers argue—that Otto's memory extends to include the notebook. After all, they notice, Otto's notes seem to play exactly the same role as memory traces in other people. Wouldn't it be chauvinistic to restrict the mind's extent to what's natural and inner?
Clark and Chalmers's paper has triggered a vigorous and continuing debate. Nonbelievers concede that numerous tight causal couplings between minds and environments exist, but they deny that it therefore makes sense to speak of an extended mind instead of a mind in a person that closely interacts with an environment. All things considered, they argue, thoughts remain in persons—never in objects like notebooks, however closely dependent a person could become on them.
Enthusiasts for the extended mind thesis insist that a close causal coupling between persons and environments can license the conclusion that the mind spreads into the environment. Some follow the argument in Clark and Chalmers that infers extendedness from the fact that external elements can play a role that would be considered as cognitive if played by something internal to a person.
Other supporters of the idea are suspicious of this argument from parity. They note that the most interesting cases of causal coupling are those in which the environment does not simply function as some ersatz internal milieu—when the involvement of external means makes possible forms of cognition that were not possible without them. For example, when pen and paper, symbolic systems, or computers make possible calculations, computations, and, ultimately, scientific theories. Those taking this position hold that it is when the environment becomes a necessary factor in enabling novel cognitive processes that the mind extends.
In The Extended Mind, philosopher Richard Menary (University of Wollongong) brings together the Clark and Chalmers paper and several responses to it. The collection, lucidly introduced by Menary, will neither definitively prove nor deal the deathblow to the idea that "the place of the mind" is the world—nor even establish that there really is such a question about "the place of the mind" that needs to be answered. Rather, the volume provides carefully drawn arguments for and against different interpretations of the extended mind thesis, often with extensive reference to empirical material. Several of the papers in the collection are excellent.
To take one fascinating idea, consider Susan Hurley on "variable neural correlates." We are comfortable with the correlation between types of experience and types of brain states, and undoubtedly such variation is one important source for the idea that the mind is in the head. Hurley notes, however, that there is also a dependence of experience on type of interaction with the environment, one not aligned to strictly neural properties. For example, when blind people haptically read Braille text, activity in the visual cortex seems to correlate with tactile experience. In people who are not blind, tactile experience correlates with activity in the tactile cortex. What explains the common enabling of tactile experience by the different kinds of cortex seems to be tactile causal coupling with the environment, rather than strictly neural type. According to Hurley, and others, the same kind of correlation-tracking reasoning that convinces us, in standard cases, that the mind is in the brain should here lead to the conclusion that the mind is not in the head.
* 1. G. Ryle, The Concept of Mind (Hutchinson, London, 1949).
* 2. J. Haugeland, Having Thought: Essays in the Metaphysics of Mind (Harvard Univ. Press, Cambridge, MA, 1998).
* 3. A. Clark, D. J. Chalmers, Analysis 58, 7 (1998).