forme di Tao mentale

Dopo aver definito l'orizzonte epistemologico-fenomenologico del loro discorso Varela, Rosch e Thompson passano a delineare i vari approcci e paradigmi delle scienze della cognizione:

What Is Cognitive Science?

In its widest sense the term cognitive science is used to indicate that the study of mind is in itself a worthy scientific pursuit. At this time cognitive science is not yet established as a mature science. It does not have a clearly agreed upon sense of direction and a large number of researchers constituting a community, as is the case with, say, atomic physics or molecular biology. Rather, it is really more of a loose affiliation of disciplines than a discipline of its own. Interestingly, an important pole is occupied by artificial intelligence - thus the computer model of the mind is a dominant aspect of the entire field. The other affiliated disciplines are generally taken to consist of linguistics, neuroscience, psychology, sometimes anthropology, and the philosophy of mind. Each discipline would give a somewhat different answer to the question of what is mind or cognition, an answer that would reflect its own specific concerns. The future development of cognitive science is therefore far from clear, but what has already been produced has had a distinct impact, and this may well continue to be the case.

From Alexandre Koyre to Thomas Kuhn, modem historians and philosophers have argued that scientific imagination mutates radically from one epoch to another and that the history of science is more like a novelistic saga than a linear progression. In other words, there is a human history of nature, a story that is well worth telling in more than one way. Alongside such a human history of nature there is a corresponding history of ideas about human self-knowledge. Consider, for example, Greek physics and the Socratic method or Montaigne's essays and early French science. This history of selfknowledge in the West remains to be fully explored. Nonetheless, it is fair to say that precursors of what we now call cognitive science have been with us all along, since the human mind is the closest and most familiar example of cognition and knowledge.

In this parallel history of mind and nature, the modem phase of cognitive science may represent a distinct mutation. At this time, science (i.e., the collection of scientists who define what science must be) not only recognizes that the investigation of knowledge itself is legitimate but also conceives of knowledge in a broad, interdisciplinary perspective, well beyond the traditional confines of epistemology and psychology. This mutation, only some thirty years old, was dramatically introduced through the "cognitivist" program (discussed later), much as the Darwinian program inaugurated the scientific study of evolution even though others had been concerned with evolution before.

Furthermore, through this mutation, knowledge has become tangibly and inextricably linked to a technology that transforms the social practices which make that very knowledge possible-artificial intelligence being the most visible example. Technology, among other things, acts as an amplifier. One cannot separate cognitive science and cognitive technology without robbing one or the other of its vital complementary element. Through technology, the scientific exploration of mind provides society at large with an unprecedented mirror of itself, well beyond the circle of the philosopher, the psycholo gist, the therapist, or any individual seeking insight into his own experience.

This mirror reveals that for the first time Western society as a whole is confronted in its everyday life and activities with such issues as: Is mind a manipulation of symbols? Can language be understood by a machine? These concerns directly touch people's lives; they are not merely theoretical. Thus it is hardly surprising that there is a constant interest in the media about cognitive science and its associated technology and that artificial intelligence has deeply penetrated the minds of the young through computer games and science fiction. This popular interest is a sign of a deep transformation: For millenia human beings have had a spontaneous understanding of their own experience - one embedded in and nourished by the larger context of their time and culture. Now, however, this spontaneous folk understanding has become inextricably linked to science and can be transformed by scientific constructions.

Many deplore this event, while others rejoice. What is undeniable is that the event is happening, and at an ever increasing speed and depth. We feel that the creative interpenetration among research scientists, technologists, and the general public holds a potential for the profound transformation of human awareness. We find this possibility fascinating and see it as one of the most interesting adventures open to everyone today. We offer this book as (we hope) a meaningful contribution to that trans formative conversation.

Throughout this book, we will emphasize the diversity of visions within cognitive science. In our eyes, cognitive science is not a monolithic field, though it does have, as does any social activity, poles of domination so that some of its participating voices acquire more force than others at various periods of time. Indeed, this sociological aspect of cognitive science is striking, for the "cognitive revolution" of the past four decades was strongly influenced through specific lines of research and funding in the United States.

Nevertheless, our bias here will be to emphasize diversity. We propose to look at cognitive science as consisting of three successive stages ... to help orient the reader, we will provide a short overview of these stages here. We have drawn them in the form of a "polar" map with three concentric rings:

The three stages correspond to the successive movement from center to periphery; each ring indicates an important shift in the theoretical framework within cognitive science. Moving around the circle, we have placed the major disciplines that constitute the field of cognitive science. Thus we have a conceptual chart in which we can place the names of various researchers whose work is both representative and will appear in the discussion that follows .

Alcuni testi rappresentativi dell'approccio riduzionista-cognitivista-interazionista alla coscienza e al Sé.
Il testo di Minsky è il paradigma all'approccio simbolico della mente e il testo fondamentale per l'Intelligenza Artificiale.
Il testo di Damasio è il classico (ed unico possibile) approccio "dal basso" all'emergenza della coscienza e del Sé effettuabile nell'ambito delle neuroscienze: si dà per scontato (dato che è evidente esperienza comune e condivisa) l'esistenza del Sé e poi si procede a definirne diverse parti e qualità suscettibili di ricerca.
Il testo di Popper e Eccles è un miscuglio tra epistemologia e neuroscienze, in cui si ipotizza che esista "il fantasma nella macchina", ovvero vi siano recessi nascosti nel cervello che nascondono il Sé e non ne permettono la completa spiegazione neuroscientifica.
Il testo di Crick, fondatore della biologia molecolare, assume in termini materialistici che la coscienza (e anche l'ipotesi dell'anima) possa venir spiegata completamente sulla base delle neuroscienze.

We begin … with the center or core of cognitive science, known generally as cognitivism. The central tool and guiding metaphor of cognitivism is the digital computer . A computer is a physical device built in such a way that a particular set of its physical changes can be interpreted as computations . A computation is an operation performed or carried out on symbols, that is, on elements that represent what they stand for. (For example, the symbol "7" represents the number 7.) Simplifying for the moment, we can say that cognitivism consists in the hypothesis that cognition-human cognition included-is the manipulation of symbols after the fashion of digital computers. In other words, cognition is mental representation: the mind is thought to operate by manipulating symbols that represent features of the world or represent the world as being a certain way. According to this cognitivist hypothesis, the study of cognition qua mental representation provides the proper domain of cognitive science, a domain held to be independent of neurobiology at one end and sociology and anthropology at the other.

Cognitivism has the virtue of being a well-defined research program, complete with prestigious institutions, journals, applied technology, and international commercial concerns. We refer to it as the center or core of cognitive science because it dominates research to such an extent that it is often simply taken to be cognitive science itself. In the past few years, however, several alternative approaches to cognition have appeared. These approaches diverge from cognitivism along two basic lines of dissent: (1) a critique of symbol processing as the appropriate vehicle for representations, and (2) a critique of the adequacy of the notion of representation as the Archimedes point for cognitive science.

The first alternative, which we call emergence … is typically referred to as connectionism. This name is derived from the idea that many cognitive tasks (such as vision and memory) seem to be handled best by systems made up of many simple components, which, when connected by the appropriate rules, give rise to global behavior corresponding to the desired task. Symbolic processing, however, is localized. Operations on symbols can be specified using only the physical form of the symbols, not their meaning. Of course, it is this feature of symbols that enables one to build a physical device to manipulate them. The disadvantage is that the loss of any part of the symbols or the rules for their manipulation results in a serious malfunction. Connnectionist models generally trade localized, symbolic processing for distributed operations (ones that extend over an entire network of components) and so result in the emergence of global properties resilient to local malfunction. For connectionists a representation consists in the correspondence between such an emergent global state and properties of the world; it is not a function of particular symbols.

The second alternative … is born from a deeper dissatisfaction than the connectionist search for alternatives to symbolic processing. It questions the centrality of the notion that cognition is fundamentally representation. Behind this notion stand three fundamental assumptions. The first is that we inhabit a world with particular properties, such as length, color, movement, sound, etc. The second is that we pick up or recover these properties by internally representing them. The third is that there is a separate subjective "we" who does these things. These three assumptions amount to a strong, often tacit and unquestioned, commitment to realism or objectivism/subjectivism about the way the world is, what we are, and how we come to know the world. Even the most hard-nosed biologist, however, would have to admit that there are many ways that the world is-indeed even many different worlds of experience - depending on the structure of the being involved and the kinds of distinctions it is able to make. And even if we restrict our attention to human cognition, there are many various ways the world can be taken to be.s This nonobjectivist (and at best also nonsubjectivist) conviction is slowly growing in the study of cognition. As yet, however, this alternative orientation does not have a well-established name, for it is more of an umbrella that covers a relatively small group of people working in diverse fields. We propose as a name the term enactive to emphasize the growing conviction that cognition is not the representation of a pregiven world by a pregiven mind but is rather the enactment of a world and a mind on the basis of a history of the variety of actions that a being in the world performs. The enactive approach takes seriously, then, the philosophical critique of the idea that the mind is a mirror of nature but goes further by addressing this issue from within the heartland of science.