Max Bill, Endless Ribbon, 1953 |
La ricerca di una via di mezzo per la descrizione della coscienza nella prospettiva enazionista porta a riconsiderare la prospettiva del senso comune:
Enaction: Embodied Cognition
Recovering Common Sense
The tacit assumption behind the varieties of cognitive realism (cognitivism,emergence, and the society of mind) has been that the world can be divided into regions of discrete elements and tasks. Cognition consists in problem solving, which must, if it is to be successful, respect the elements, properties, and relations within these pregiven regions.
This approach to cognition as problem solving works to some degree for task domains in which it is relatively easy to specify all possible states. Consider for example the game of chess. It is relatively easy to define the constituents of the "space of chess": there are positions on the board, rules for movements, turns that are taken, and so on. The limits of this space are clearly defined; in fact, it is an almost crystalline world. It is not surprising, then, that chess playing by computer is an advanced art.
For less circumscribed or well-defined task domains, however, this approach has proved to be considerably less productive. Consider, for example, a mobile robot that is supposed to drive a car within a city. One can still single out in this "driving space" discrete items, such as wheels and windows, red lights, and other cars. But unlike the world of chess playing, movement among objects is not a space that can be said to end neatly at some point. Should the robot pay attention to pedestrians or not? Should it take weather conditions into account? Or the country in which the city is located and its unique driving customs? Such a list of questions could go on forever. The driving world does not end at some point; it has the structure of ever-receding levels of detail that blend into a nonspecific background. Indeed, successfully directed movement such as driving depends upon acquired motor skills and the continuous use of common sense or background know-how.
Such commonsense knowledge is difficult, perhaps impossible, to package into explicit, propositional knowledge - "knowledge that" in the philosopher's jargon-since it is largely a matter of readiness to hand or "knowledge how" based on the accumulation of experience in a vast number of cases. Recent examinations of how skills are acquired appear to confirm this point.1 Furthermore, when we enlarge the task domains from artificial microworlds to the world at large, it is not clear that we can even specify what is to count as an object independent of the type of action that is being performed. The individuation of objects, properties, and events appears to vary according to the task at hand.
These points are not new to the field of cognitive science, although their full import has only begun to be appreciated. Indeed, it is fair to say that by the 1970s, after two decades of humblingly slow progress, it dawned on many workers in cognitive science that even the simplest cognitive action requires a seemingly infinite amount of knowledge, which we take for granted (it is so obvious as to be invisible) but which must be spoon-fed to the computer. The early cognitivist hope for a general problem solver had to be abandoned in favor of programs that would run in local knowledge domains, where small-scale problems could be solved and where the programmer could put into the machine as much of her background knowledge as was necessary. Similarly, the current connectionist strategy depends either on restricting the space of possible attractors by means of assumptions about the known properties of the world, which are incorporated as additional constraints for regularization, or, in more recent models, on using backpropagation methods where learning resembles the imitation of an external model. Thus in both cognitivism and connectionism, the unmanageable ambiguity of background common sense is left largely at the periphery of the inquiry, with the hope that it will somehow eventually be clarified.
If, however, our lived world does not have predefined boundaries, then it seems unrealistic to expect to capture commonsense understanding in the form of a representation-where representation is understood in its strong sense as the re-presentation of a pregiven world. Indeed, if we wish to recover common sense, then we must invert the representationist attitude by treating context-dependent know-how not as a residual artifact that can be progressively eliminated by the discovery of more sophisticated rules but as, in fact, the very essence of creative cognition.
This attitude toward common sense has begun to affect the field of cognitive science, especially in artificial intelligence. We should note, however, that the philosophical source for this attitude is to be found largely in recent Continental philosophy, especially in the school of philosophical hermeneutics, which is based in the early work of Martin Heidegger and his student Hans Gadamer.
The term hermeneutics originally referred to the discipline of interpreting ancient texts, but it has been extended to denote the entire phenomenon of interpretation, understood as the enactment or bringing forth of meaning from a background of understanding. In general, Continental philosophers, even when they explicitly contest many of the assumptions underlying hermeneutics, have continued to produce detailed discussions that show how knowledge depends on being in a world that is inseparable from our bodies, our language, and our social history - in short, from our embodiment.
Although several cognitive scientists have recently turned to these discussions for inspiration, the spontaneous philosophy of cognitive science continues to resist such a nonobjectivist orientation. The varieties of cognitive realism are in particular strongly tied to analytic philosophy, which tends to view folk psychology as a tacit theory in need of either reduction or replacement. Indeed, it is fair to say that analytic philosophy in general resists this notion of cognition as embodied understanding.
Thus as Mark Johnson notes in a recent work,
The idea that understanding is an event in which one has a world, or, more properly, a series of ongoing related meaning events in which one's world stands forth, has long been recognized on the Continent, especially in the work of Heidegger and Gadamer. But Anglo-American analytic philosophy has steadfastly resisted this orientation in favor of meaning as a fixed relation between words and the world. It has been mistakenly assumed that only a viewpoint that transcends human embodiment, cultural embeddedness, imaginative understanding, and location within historically evolving traditions can guarantee the possibility of objectivity.The central insight of this nonobjectivist orientation is the view that knowledge is the result of an ongoing interpretation that emerges from our capacities of understanding. These capacities are rooted in the structures of our biological embodiment but are lived and experienced within a domain of consensual action and cultural history.
They enable us to make sense of our world; or in more phenomenological language, they are the structures by which we exist in the manner of "having a world." To quote Johnson once more,
Meaning includes patterns of embodied experience and preconceptual structures of our sensibility (i.e., our mode of perception, or orienting ourselves, and of interacting with other objects, events, or persons). These embodied patterns do not remain private or peculiar to the person who experiences them. Our community helps us interpret and codify many of our felt patterns. They become shared cultural modes of experience and help to determine the nature of our meaningful, coherent understanding of our "world."Although these themes are derived from Continental philosophy, most of the Continental discussions have proceeded without taking into consideration scientific research on cognition-the major exception being the early work of Merleau-Ponty. The challenge posed by cognitive science to the Continental discussions, then, is to link the study of human experience as culturally embodied with the study of human cognition in neuroscience, linguistics, and cognitive psychology. In contrast, the challenge posed to cognitive science is to question one of the more entrenched assumptions of our scientific heritage-that the world is independent of the knower. If we are forced to admit that cognition cannot be properly understood without common sense, and that common sense is none other than our bodily and social history, then the inevitable conclusion is that knower and known, mind and world, stand in relation to each other through mutual specification or dependent coorigination.
If this critique is valid, then scientific progress in understanding cognition will not be forthcoming unless we start from a different basis from the idea of a pregiven world that exists II out there" and is internally recovered in a representation. In recent years, a few researchers within cognitive science have taken this critique from the philosophical level into the laboratory and into specific work in AI. These researchers have put forth concrete proposals that involve a more radical departure from cognitivism than is found in the emergence approach, and yet they incorporate the ideas and methods developed within this context.