Six Views of Embodied Cognition
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Psychonomic Bulletin & Review 2002, 9 (4), 625-636 THEORETICAL AND REVIEW ARTICLES Six views of embodied cognition MARGARET WILSON University of California, Santa Cruz, California The emerging viewpoint of embodied cognition holds that cognitive processes are deeply rooted in the body’s interactions with the world. This position actually houses a number of distinct claims, some of which are more controversial than others. This paper distinguishes and evaluates the following six claims: (1) cognition is situated; (2) cognition is time-pressured; (3) we off-load cognitive work onto the environment; (4) the environment is part of the cognitive system;(5) cognition is for action; (6) off- line cognition is body based. Of these, the first three and the fifth appear to be at least partially true, and their usefulness is best evaluatedin terms of the range of their applicability.The fourth claim,I argue, is deeply problematic. The sixth claim has received the least attention in the literature on embodied cognition, but it may in fact be the best documented and most powerful of the six claims. There is a movement afoot in cognitive science to grant has emphasizedsensory and motor functions,as well as their the body a central role in shaping the mind. Proponents of importance for successful interaction with the environment. embodied cognitiontake as their theoretical starting point Early sources includethe viewof 19thcentury psychologists not a mind working on abstract problems, but a body that that there was no such thing as “imageless thought” (Good- requires a mind to make it function. These opening lines win, 1999); motor theories of perception such as those sug- by Clark (1998) are typical:“Biologicalbrains are first and gested by William James and others (see Prinz, 1987, for a foremost the control systems for biologicalbodies. Biolog- review); the developmental psychology of Jean Piaget, ical bodies move and act in rich real-world surroundings” which emphasized the emergence of cognitive abilities out (p. 506). of a groundwork of sensorimotor abilities; and the ecologi- Traditionally,the various branches of cognitivescience cal psychology of J. J. Gibson, which viewed perception in have viewed the mind as an abstract information proces- terms of affordances— potential interactions with the envi- sor, whose connections to the outside world were of little ronment. In the 1980s, linguists began exploring how ab- theoretical importance. Perceptual and motor systems, stract conceptsmay be based on metaphorsfor bodily,phys- though reasonable objects of inquiry in their own right, ical concepts (e.g., Lakoff & Johnson, 1980). At the same were not considered relevant to understanding “central” time, within the field of artificial intelligence, behavior- cognitive processes. Instead, they were thought to serve based robotics began to emphasize routines for interacting merely as peripheral input and outputdevices.This stance with the environment rather than internal representations was evident in the early decades of cognitive psychology, used for abstract thought (see, e.g., Brooks, 1986). when most theories of human thinking dealt in proposi- This kind of approach has recently attained high visi- tional forms of knowledge. During the same time period, bility,under the banner of embodied cognition.There is a artificial intelligencewas dominated by computer models growing commitment to the idea that the mind must be un- of abstract symbol processing. Philosophy of mind, too, derstood in the context of its relationship to a physical made its contribution to this zeitgeist, most notably in body that interactswith the world. It is argued that we have Fodor’s(1983) modularityhypothesis.According to Fodor, evolved from creatures whose neural resources were de- central cognitionis not modular, but its connectionsto the voted primarily to perceptual and motoric processing, and world are. Perceptual and motor processing are done by whose cognitive activity consisted largely of immediate, informationally encapsulated plug-ins providing sharply on-lineinteractionwith the environment.Hence human cog- limited forms of input and output. nition, rather than being centralized, abstract, and sharply However, there is a radically different stance that also has distinct from peripheral input and output modules, may in- roots in diverse branches of cognitive science. This stance stead have deep roots in sensorimotor processing. Although this general approach is enjoying increasingly Correspondence should be addressed to M. Wilson, Department of broad support, there is in fact a great deal of diversity in Psychology, University of California, Santa Cruz, CA 95064 (e-mail: the claims involved and the degree of controversy they at- [email protected]). tract. If the term embodied cognitionis to retain meaning- 625 Copyright 2002 Psychonomic Society, Inc. 626 WILSON ful use, we need to disentangle and evaluate these diverse ceptual information continuesto come in that affects pro- claims. Among the most prominent are the following: cessing, and motor activity is executed that affects the 1. Cognition is situated. Cognitiveactivitytakes place environment in task-relevant ways. Driving, holding a in the context of a real-world environment, and it inher- conversation, and moving around a room while trying to ently involves perception and action. imagine where the furniture should go are all cognitiveac- 2. Cognition is time pressured. We are “mind on the tivities that are situated in this sense. hoof” (Clark, 1997),and cognitionmust be understoodin Even with this basic definition of what it means for cog- terms of how it functions under the pressures of real-time nition to be situated, we can note that large portions of interaction with the environment. human cognitive processing are excluded. Any cognitive 3.We off-load cognitivework onto the environment. activity that takes place “off-line,” in the absence of task- Because of limits on our information-processing abilities relevantinputand output,is by definitionnot situated.Ex- (e.g., limits on attention and working memory), we exploit amples include planning,remembering, and day-dreaming, the environmentto reduce the cognitiveworkload.Wemake in contexts not directly relevant to the content of plans, the environment hold or even manipulate information for memories, or day-dreams. us, and we harvest that information only on a need-to- This observation is not new (see, e.g., Clark & Grush, know basis. 1999; Grush, 1997), but given the rhetoric currently to be 4. The environment is part of the cognitive system. found in the situated cognition literature, the point is The information flow between mind and world is so dense worth emphasizing. By definition, situated cognition in- and continuous that, for scientists studying the nature of volves interaction with the things that the cognitive activ- cognitive activity, the mind alone is not a meaningful unit ity is about. Yetone of the hallmarks of human cognition of analysis. is that it can take place decoupledfrom any immediate in- 5. Cognition is for action. The function of the mind is teraction with the environment. We can lay plans for the to guide action, and cognitive mechanisms such as per- future, and think over what has happened in the past. We ception and memory must be understood in terms of their can entertain counterfactuals to considerwhat might have ultimate contribution to situation-appropriate behavior. happenedif circumstanceshad been different. We can con- 6. Off-line cognition is body based. Even when de- struct mental representations of situations we have never coupled from the environment, the activity of the mind is experienced,based purely on linguistic input from others. groundedin mechanisms that evolvedfor interactionwith In short, our ability to form mental representations about the environment—that is, mechanisms of sensory pro- thingsthat are remote in time and space, which is arguably cessing and motor control. the sine qua non of human thought, in principle cannot Frequentlyin the literatureon embodiedcognition,sev- yield to a situated cognition analysis. eral or all of these claims are presented together as if they An argument might be made, though,that situated cog- represented a single point of view.This strategy may have nition is nevertheless the bedrock of human cognition,due its uses, as for example in helping to draw a compelling to in our evolutionary history. Indeed, it is popular to try picture of what embodied cognition might be and why it to drive intuitions about situated cognition by invoking a might be important. This may have been particularly ap- picture of our ancestors relying almost entirely on situated propriate at the time that attention first was drawn to this skills.Before we got civilized,the argument goes, the sur- set of ideas, when audiences were as yet unfamiliar with vival value of our mental abilities depended on whether this way of conceptualizingcognition.The time has come, they helped us to act in direct response to immediate situ- though,to take a more careful look at each of these claims ations such as obtaining food from the environment or on its own merits. avoiding predators. Thus, situated cognition may repre- sent our fundamentalcognitive architecture, even if this is Claim 1: Cognition Is Situated not always reflected in the artificial activities of our mod- A cornerstone of the embodied cognition literature is ern world. the claim that cognitionis a situated activity(e.g., Chiel & This view of early humans, though, most likely exag- Beer, 1997; Clark, 1997; Pfeifer & Scheier, 1999; Steels gerates the role of these survival-related on-line activities & Brooks, 1995; a commitment to situated cognition can in the daily lives of early humans. With respect to obtain- also be found in the literature on dynamical systems— ing food, meat eating was a late addition to the human e.g., Beer, 2000; Port & van Gelder, 1995; Thelen & Smith, repertoire, and even after the onset of hunting, the large 1994; Wiles & Dartnall, 1999). Some authors go so far as majority of calories were probably still obtained from to complain that the phrase “situated cognition” implies, gathering.