(c) Amy Ione, PO Box 12748, Berkeley, CA 94712 USA
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In 1957, Herbert Simon, one of the founding fathers of artificial intelligence, was quoted as saying we now live in a world where machines can think. Today, almost fifty years later, many of his critics remain unconvinced that this is the case. As these critics point out, and I count myself among them, it would perhaps be more accurate to say that the combination of brain research and computer technologies has helped us articulate some of the questions we have about human consciousness. More specifically, technology has failed to replicate intelligence, the functions within the brain, or even the 'sense' of self known to humans. Still, technology has been useful in fostering some measure of understanding about how symbolic logic and connectionist dynamics are integrated into our experience of the self. Technologies have also supplemented our explicit data and thus helped us re-consider long-standing conclusions about the brain, the mind, and consciousness.
This paper probes the areas noted above in the following four ways. First I draw upon the work of William James to consider the question: what is consciousness? Then I add some perspective to this question by juxtaposing ideas about consciousness with historical and contemporary views about technology, the brain and the self. In the third section, I use this analysis to explore computer technologies, Baars' Global Workspace theory, and Stapp's Heisenberg/James model. These additional examples then allow me to conclude with a model of consciousness that shows why both imaginative and applied views are necessary if we are to effectively communicate and continually build on our knowledge of the brain and the self.
What is consciousness?
The question "what is consciousness?" is my first concern because it is probably one of the oldest unanswered questions among people of all cultures. As we know, western culture has had some resistance toward even asking the question scientifically. As we also know, this resistance resulted from three factors: (1) the adoption of the assumption that the mind and the brain were of different substances created a difficulty in seeing the conscious mind as a biological phenomenon. (2) Science found no place for consciousness in its physical models, and (3) the nature of scientific reductionism itself.
It is with this historical perception of 'resistance' in mind that I want to turn to the following piece of a 1924 conversation between Werner Heisenberg and Niels Bohr. Heisenberg noted that this conversation took place when he and Bohr were on a walking tour of Denmark, Bohr's homeland. Please note how Bohr's words to Heisenberg upon their arrival at Kronberg Castle both accept and reshape stereotypical assumptions about science and scientists.
"Isn't it strange how this castle changes as soon as one imagines that Hamlet lived here. As scientists we believe that a castle consists only of stones, and admire the way the architect put them together. The stone, the green roof with its patina, the woodcarvings in the church, constitute the whole castle. None of this should be changed by the fact that Hamlet lived here, and yet it is changed completely. Suddenly the walls and the ramparts speak a different language. The courtyard becomes an entire world, a dark corner reminds us of the darkness of the soul, we hear Hamlet's 'To be or not to be.' Yet all we really know about Hamlet is that his name appears in a thirteenth-century chronicle. No one can prove that he really lived here. But everyone knows the questions Shakespeare had him ask, the human depths he was made to reveal, and so he too had to be found a place on earth, here in Kronbreg." (Bruner, 1966, p. 45)
Clearly Bohr first acknowledges the cultural assumption that scientists are only concerned with the physical and then refutes it contextually - through his own personal ruminations on deep philosophical issues. Bohr's words become even more intriguing when we juxtapose them with some ideas of the philosopher and psychologist William James (1842-1910). James too used the power of Shakespeare's Hamlet to raise questions about deep philosophical issues that pertain to consciousness. James, however, turned the questions around, asking how mechanistic explanations 'fit' with the activity of human consciousness. James' point was that if the brain is merely a complex machine of many reflexes, how could it explain Shakespeare's writing of Hamlet? Could a mechanistic explanation adequately account for Shakespeare's thoughts and emotions? (Scott, 1996)
Putting these perspectives together suggests that what we mean by consciousness can refer to the kinds of thoughts and emotions that stir us when we read Hamlet. Consciousness can also refer to the nature of Shakespeare's brain and self when penning Hamlet. In addition, given Bohr's words, it seems thoughts and emotions can interpenetrate when we interact with what the physical is and represents to us. Given James' conclusions, it is easy to forget that science lives within a culture where scientists, like Bohr and Heisenberg, often do raise philosophical questions with one another that are likely to inform the problems they choose to study as scientists, if not their science per se. More important to this discussion, these kinds of contextual differences are rarely evident in the logical approach to experience that has traditionally been used in western science and philosophy. This kind of logical positioning of ideas is, in my opinion, especially evident when consciousness theorists reference the radical empiricism of William James. ( For examples, see Baars, 1988; Baars, 1996; Harman, 1994; Stapp, 1993)
1. William James and radical empiricism
One point that often seems to be subsumed when James' work is presented is that James' radical empiricism is not intended to answer the question of what consciousness is. On the contrary, James saw himself as a radical empiricist and said that, as an empiricist, he is "content to regard . . . most assumed conclusions concerning matters of fact as hypotheses liable to modification in the course of future experience." (James, 1956, p. vii). As a radical he "treats the doctrine of monism itself as a hypothesis, and . . . [sees] the difference between monism and pluralism; as we find it, the most pregnant difference in philosophy." . . James then sums up his views by saying "there is no possible point of view from which the world can appear an absolutely single fact." 1 (James, 1956, p. ix.) In short, James explicitly objected to the exclusion of human experience and personal consciousness in philosophy, as these additional words illustrate:
"We have so many businesses with nature that no one of them yields us an all-embracing clasp. The philosophic attempt to define nature so that no one is left out, so that no one lies outside the door saying, 'Where do I come in?' is sure to fail in advance." (James, 1987, p. 644)
My reason for stressing James' view here is two-fold. On the one hand, I want to point out that James thought deeply about how to change the sterile approach to experience that dominated philosophical discourse in his day. Yet, on the other hand, he did so in a world where the functions of neurons had not yet been defined. It was a world with a pre-relativity, pre-quantum theory, pre-DNA worldview. As we so often neglect to mention, all of this colored his perception of what physicality is and how life works. It was a coloration that reflected his culture, a culture that was similar but yet different from our own. 2
More significantly, despite the way his understandings of the physical world differed from our own, the roots of James' worldview and the ramifications of James' influence, live on within our minds - minds that have been shaped by a culture that has consistently had problems integrating experience with science and philosophy. The specific kinds of problems I am referring to include: (1) how can we consider consciousness as intrinsically related to people? (2) How do humans mediate the structure and dynamics of life if our scientific and philosophical systems have no 'category' for life as we experience it? And, (3) how do people actually resolve philosophical and scientific ideals of perfection in a world where we frequently observe a lack of uniformity - one could say deviance, one could say individuality, one could say plurality - within individuals, nature, and communities. 3 James, and this is his appeal, struggled with these problems throughout his life.
2. History and consciousness
Before beginning to consider James in relation to contemporary ideas about technology, the brain and the self, I believe some additional thoughts about historical ideas will strengthen this discussion overall. Let me stress that in bringing history into the discussion I am asserting that the historical story shows that the focus of western culture has not been a precise one and that the changes from era to era 4 have been stochastic and nonlinear. By extension, the contextual story suggests that history, like psychology, helps us reference how we came to be who we are. Moreover, looking at other periods shows us that each age has its own view and that science, like culture, is a part of 'time'.
For example, while the philosophical distinction between mind and body in western thought can be traced to the Greeks, it is in the seminal work of the French mathematician, philosopher, and physiologist, RenÚ Descartes (1596-1650) that we find the first systematic account of the mind/body relationship. As is well known, his coupling of the mind/body relationship with his mechanistic orientation has led to his legacy as the father of the mind/body problem. 5 Yet, I would assert that this label is incomplete and thus misleading. More specifically, like many people in the seventeenth century, Descartes used mechanistic metaphors to capture his belief in a perfect God and a perfectly functioning universe. 6 Moreover, he was not just an abstract thinker. Compelled by a heartfelt desire to know who he was and how people and nature were related to God he not only meditated on the nature of consciousness, he also visited the slaughterhouses in Amsterdam where he actually examined and sketched brains. (Brazier, 1984). His anatomical observations were then combined with innovative ideas and eventually had a tremendous impact on the history of neurophysiology.
I suspect this aspect of Descartes work is less visible because Descartes' ideas about the nervous system failed the crucial test of experimental proof. Yet, and this is my point, he did identify what needed to be pursued in later studies. He recognized that we must consider how the brain can sense the outside world, how the nerve can cause the muscle to contract, and how the contraction of one muscle group must necessarily be accompanied by the relaxation of its opponent. Moreover, in the long run, it may be said that Descartes studies of the brain were more valuable than his Cartesian legacy. I say this because they alerted researchers to physiological necessities by asserting that the biological body was governed by the same physical laws as the rest of the phenomena of the universe. (Brazier, 1984). This idea, of course, still survives today.
The larger point is that this combination of mechanistic analogy, philosophic method, and scientific investigation was evident before Descartes, was adopted by Descartes, continued to be used after Descartes and it is in use today. Thus, while technologies have significantly changed, the mechanical analogies have still offered an ongoing means to communicate about how emerging concepts and data might fit together. For example, Sigmund Freud (1856-1939) often compared his model of the mind to hydraulic and electromagnetic systems. On the other hand, Sir Charles Sherrington, an English physiologist, who lived between 1857-1952, and who won the 1932 Noble Prize for discoveries on the function of neurons, was strongly committed to studies that unified the self, the brain, and the community. The following passage from Sherrington's Man on his nature, conveys this.
[The actual cells of the brain] . . . if we pursue the simile of the telephone system, are not the mere wires but are the actual exchange; they do the retransmitting. . . . . Physiology has got so far therefore as examining the activity in the 'mental' part of the brain when activity there is in normal progress. . . . But has it brought us to the 'mind'? It has brought us to the brain as a telephone-exchange. All the exchange consists of is switches. What we wanted really of the brain was, it would seem, the subscribers using the exchange. The subscribers with their thoughts, their desires, their anticipations, their motives, their anxieties, their rejoicing. If it is mind we are searching the brain for, then we are supposing the brain to be more than a telephone-exchange. We are supposing it a telephone-exchange along with the subscribers as well." (Sherrington, 1941, p. 282)
3. Applied and imaginative views of consciousness
As I noted earlier, these models resonate with work being done today. For example, research into artificial intelligence (AI) has visited - and revisited - many of the theoretical issues discussed throughout history in regard to mechanical and biological systems. AI has also stimulated the kinds of questions about connective and symbolic systems that have traditionally been framed through discussions about appearance and reality and thus have traditionally been relegated to the physics/ metaphysics debates. One fascinating aspect of AI reasearch, moreover, is that the changing tide of AI has proved to be very adept in showing us that many of our longstanding beliefs about the mind and intelligence were simply wrong. (Crevier,1992). Thus, in sum, AI has proved to be useful in revealing the complexity of the mind and its functions. This is especially intriguing in light of the other technologies that are also a part of our times.
For example, imaging technologies, such as CTs, MRIs and PET scans have shown us how the brain functions and have also revealed that a great deal has been invisible to us. What stands out here is that we are only beginning to develop methods for the study of complex systems and the 'invisible' processes that are somehow involved with the brain and consciousness. In other words, like the microscope and the telescope, methods of quantitative imaging have helped us extend our natural vision, and thus have helped us build a better understanding of how the brain and the body 'work'. Nonetheless, we are unable, at this point, to comprehensively verbalize what goes on in the brain when we perform functions related to explicit conscious - such as face recognition and pattern recognition. In addition, researchers today, remain unable to see implicit assumptions, even their own.
This is why I would assert that even if we do conjure up a mechanical model of how the brain works we will still need to recognize that brains work personally and in a social context. A simple model will not address how we exchange the information we have garnered and how we pass it on to future generations. This is not to negate the value of technology and mechanism in our psychological research, but to give you something to reflect on as I turn to Bernie Baars Global Workspace (GW) theory.
1. The Global Workspace (GW)
Baars Global Workspace theory (GW) (1988, 1996) shows how technological advances often come together with historical and theoretical issues when we postulate new models. The GW theory itself is presented as a functional, experimentally conceived, and connectionist-type psychological theory. James' influence is evident in the theoretical assumption that contexts 7 "are not incidental phenomena that confound our careful experiments." Rather, according to Baars, they are "quintessential in psychology." (Baars, 1988, p. 176).
Overall, Baars associates conscious experience with a rather simple architecture of the psychological system and says his theory was "originally developed to deal precisely with the problem of unifying many ambiguous or partial sources of information into a single, unified solution." 8 (Baars, 1988, p. 148). Anyone who wants a detailed analysis of the model should refer to my paper, "Implicit cognition in scientific speculation and development." 9 (Ione, 1997).
My focus here is limited to the methodological design, which Baars calls contrastive phenomenology. This modeling technique is supposed to allow researchers to combine the ambiguous and partial sources of information we have today by combining experiment, experience, and events. Baars says this unification of various perceptions allows us to see that data derived from various modes come together in a way that shows that the workings of the brain, like the cells of the human body, are widely distributed and yet function as a unity.
Typically data is collected by coupling brain-imaging techniques with reports of psychological and subjective experience as recorded by subjects. Thus, one experiment tests individuals on their ability to retain particular numbers in their minds while trying to react to stimuli presented to them in the laboratory. Another experiment uses PET scans of an individual playing a computer game, TETRIS, to show that when the subject is learning how to play the game, there is evidence of increased neural activity. Baars concludes that scans revealing less conscious activity indicates the subject has mastered the details needed to fulfill the task at hand. (Baars, 1996).
My primary objection is that these experiments do not model the dynamics of experience in real time. 10 This is actually why the falsification parameter Baars' articulates as 'try it yourself,' is really a verification option, not a means for falsification. And it is a verification of something done in a rather contrived framework.
I must add that there is an ironic element here. I say this because Baars claims the Global Workspace model was influenced by James' work and yet Baars offers precisely the kind of universal unification model James was questioning, as the following passage illustrates.
"The particular intellectualistic difficulty that had held my own thought so long in a vise was . . . the impossibility of understanding how 'your' experience and 'mine,' which 'as such' are defined as not conscious of each other, can nevertheless at the same time be members of a world experience defined expressly as having all its parts co-conscious, or known together. The definitions are contradictory, so the things defined can in no way be united . . . Things are 'with' one another in many ways, but nothing includes everything, or dominates over everything. The word 'and' trails along after every sentence. Something always escapes. 'Ever not quite' has to be said of the best attempts made anywhere in the universe at attaining all-inclusiveness. . . . However much may be collected, however much may report itself as present at any effective center of consciousness or action, something else is self-governed and absent and unreduced to unity." (James, 1987, pp. 729, 777)
In sum, the kind of unification model Baars offers might be technically competent and useful to some degree, but it does not look at embodied consciousness. It looks at activities that parallel consciousness. 11
2. Connective models
Many phenomenological models attempt to address this kind of problem by offering simulations of embodied consciousness. Autopoiesis (auto=self and poiesis = making) is the term often used to speak of this, for it suggests life is an ongoing reconstitution which includes self-production and self-renewal. 12 This kind of model endeavors to speak of life as a mechanized 13 living system. What this means is that life and mechanism do not become Platonic abstractions, divorced from change and time. Rather, the mechanistic system is attached to its activity. Thus the autopoetic concept offers a living systems-like alternative to nineteenth century vitalism because it actually demonstrates a natural re-organization of components. It is a model where the parts clearly exist in relationship to one another and offer a convincing example of how a mechanical system can be a biological activity.
What the embodied connective model cannot explain, however, is how we reconceptualize patterns of organization - individually and communally. For example, our minds and our sense experience agree that it appears as if the sun circles the earth, rising in the east each morning and then setting in the west. This perception in fact led to the long-term acceptance of the Ptolemaic (earth-centered) model of the solar system and the ongoing revision of this model by the community. This ongoing revision offers an example of how an informational processing model can revise standard perceptions and fail to enlarge our scope of information. My point is that once we conceptualized why this earth-centered perception is inaccurate, we did not stop seeing the sun rise and then set as if it circled the earth. Rather, we recognized we had an incomplete perspective of the overall pattern of organization. In other words, while the Ptolemaic perception matched our embodied perceptual experience, it did not match the complexity of the larger system in a variety of ways that still continue to be brought to our attention. 14
3. Envisioning Alternatives
Given this, I want to suggest that rather than assuming that our embodied experience completely grasps the whole picture - or that we need some kind of logical fix to account for what we cannot define. 15 - A better approach might be to look at other options. We might ask questions that spark our imaginations - like how can we design an informational processing model that includes actual information we cannot yet conceptualize in a connected way? How can we design these models so that they are not simply controlled experiments or contrived metaphors - but also have a quantitative component to help us replicate and communicate about the connections?
Quantum theory and relativity have given us some leverage for this kind of modeling. Their entry into our world has compelled us to actively ask how to construct a model that brings together parts of reality that we have glimpsed and not yet precisely connected to our living experience. While many views have been offered in an effort to enlarge our understanding of micro- and macro- domains within consciousness studies ( For examples see Lockwood, 1989; Penrose, 1989; Stapp, 1993), I must admit that I find Henry Stapp's approach to be the most convincing to date. 16
While I would reject Stapp's dualistic conclusion, for reasons that are beyond the scope of this discussion, I still believe his approach offers a promising direction for developing a more comprehensive contextual model. It is a direction that will prove useful in bringing current ideas about the brain and the self into a larger context. The appeal of Stapp's Heisenberg/James model, from my perspective, is that it uses a naturalistic design and appears to have the capacity to genuinely be more connective than contrastive in spirit - once the links are clearly and quantitatively conceptualized. The combination of the Heisenberg's principle and James' ideas also allow us to explain consciousness in a way that can remain open and still be aligned with both mechanistic and organic measures. As such, this kind of revision would offer a means to move James' beyond his time and provide the kind of solution that can include a multidimensional perspective - as well as an underlying connectedness. 17
In conclusion, it is because the brain and the self are biological and yet viewed from conceptual vantage points that I am proposing we address them by asking what information and experience are. To do this, our modeling techniques must include how the brain, people, and modeling techniques change as we study them. It is only with this type of complexity that our models will be able to accommodate life and experience. To do so, moreover, our imaginations must first devise possibilities and then find ways to concretely apply and communicate about the alternative possibilities with others. History shows that effective models take form in just this way. People, living people, devise and then use analogies to give breadth to ideas, to express real concerns, and to create a matrix that has the potential to be updated. It is a part of the process of life where new generations respond to their perceptions of what we teach them and what they discover on their own. . . . We can choose many paths as we participate in this process . . .
*This paper was delivered on August 22, 1996 as a part of the "The Brain and Self" conference sponsored by Consciousness Studies at the University of Arizona, Elsinore, Denmark, August 21-24, 1997
1 James, of course, like his predecessors - Plato, Descartes, and Kant - had some measure of difficulty conceptualizing how accepted definitions about the physical world 'fit' with actual personal experience. As James' work indicates, his pragmatism and radical empiricism developed as he questioned how the philosophical framework idealized and universalized life.
2 Of course, this may account for our perception that James drew confused conclusions about mechanism, (Scott, 1996) for example.
3 Victor H. Yngve's book From Grammar to Science: New Foundations for General Linguistics (Yngne, 1996) was instrumental in helping me develop some of these ideas. His discussion of the historical problems found in so-called 'scientific' studies of language apply to the overall study of consciousness.
4 Richard Olson offers a good picture of the nonlinearity of science in his Science Deified and Science Defied books. (1982, 1990).
5 Others shared this interest in mechanism. For example, Blaise Pascal (1623-1662) who was a contemporary of Descartes, is often given credit for designing the first adding machine at this time and, I might add, was not pleased when it was termed a 'mechanical brain'. (Brazier, 1984). Gottfied Wilhelm Leibniz (1646-1716), on the other hand, compared the mind to a mill and spent many years considering how it might be possible to resolve tricky conceptual issues by formalizing concepts numerically.
6 As the historian of science Richard Olson has said, "[T]he Renaissance tradition of engineering and the earlier medieval rise of mechanical technologies, which had harnessed wind, water, and animal power for productive activities, provided a suggestive source of 'familiar' analogs to draw upon. Mechanical devices of all sorts - grindstones, waterwheels, locks of canals, pumps, and above all, clockworks, and the closely related automat (simulated persons or animals moved by elaborate hidden mechanisms of strings, springs, weights, rollers, and hydraulic devices) - suggested themselves as analogs for natural phenomena. . . . Vastly more important was the 'clock of wisdom' tradition which appeared in fourteenth and fifteenth century illuminated manuscripts. In this artistic and literary tradition, the harmonious arrangement of machinery and bells in a striking mechanical clock was called upon to proclaim the wisdom of God and to inspire devotion. The 'clock of wisdom' tradition . . . referred directly to the order, regularity, and harmonious characteristics of clockworks as those features which bring to mind God's wisdom. (Olson, 1982, p. 24-25)
7 Baars defines contexts as "a system that shapes consciousness experience without itself being conscious at that time . . . Contexts include currently unconscious expectations that shape conscious experience, and currently unconscious intentions that shape voluntary actions. . . . the word 'context' is not just any mental representation: It is an unconscious representation that acts to influence another, conscious representation." (Baars, 1988, pp. 138-139).
8 Toward this end, the model is premised on the idea that the detailed workings of the brain, like the cells of the human body, are widely distributed. Therefore, there is no centralized command that tells the neurons what to do. Rather the doing is an ongoing exchange similar to actors, audience, and director. Thus, by definition, the central workspace is much like the central staging area of a theater.
9 There are five key limitations within the Global Workspace model that should be noted. (1) Baars' failure to adequately circumvent the homunculus issue. (2) Baars' failure to offer a context for ongoing innovation and invention. (3) There is a design problem in his contrastive phenomenology. (4) Imagination is left out of the experiential analysis. (5) It is a closed model. (see Ione, 1997)
10 Antonio R. Damasio's case of Eliot offers an excellent counterexample. Elliot was a man who performed normally on every test given him - yet was unable to function effectively in life. Damasio summed up the situation as follows: "While Elliot's preserved performance was consonant with his superior scoring on conventional tests of memory and intellect, it contrasted sharply with the defective decision-making he exhibited in real life. . . . At the end of one session, after he had produced an abundant quantity of options for action, all of which were valid and implementable, Eliot smiled, apparently satisfied with his rich imagination, but added: 'and after all this, I still wouldn't know what to do!" (Damasio, 1994, p. 49)
11 Baars has responded to this conclusion as follows: "Some philosophers maintain that the experimental descriptions we have collected in a century of sensory science may parallel conscious experience without actually resulting from it .. . . But this seems utterly implausible to an empirical scientist. If the overwhelming majority of people say a pencil is red, if they can match it with other red things and distinguish it from blue and green pencils; it their eyes have red receptors, and color cells in the visual cortex fire a red code, what else would they be having but an experience of red." (Baars, 1996, p. 34)
12 Humberto Maturana and Francisco Varela first introduced the word in 1973.
13 "The most striking feature of an autopoietic system is that it pulls itself up by its own bootstraps and becomes distinct from its own dynamics, in such a way that both things are inseparable." (Maturana & Varela, 1992, pp. 46-47).
14 The perceptual problem, of course, was exacerbated when human perceptions were combined with implicit assumptions, like the idea that only circles could explain planetary orbits correctly. The problem, according to the historical record, is that the combination of experience and intelligence had difficulty in formulating other options. Thus, information was re-organized and often embodied but neither of these modes necessarily upgraded the quality of our information.
15 This, of course, has been a traditional philosophical (and religious) ploy. It is now most evident in Chalmers' call to define consciousness as a fundamental property of the universe. (Chalmers, 1996)
16 Stapp puts it this way. "Advances in science often unify conceptually things previously thought to be unconnected . . . My thesis here is that the integration of consciousness into science requires considering together two outstanding fundamental problems in contemporary science, namely the problem of connection between mind and brain, and the problem of measurement in quantum theory." (Stapp, 1993, p. 145)
17 "The fundamental problem here is how can one logically form entities that are intrinsically - i.e., strictly within themselves, without the help of some outside binding agent - complex wholes, within a logical framework that is fundamentally reductionistic - i.e., within a framework in which everything is asserted to be nothing but an aggregation of simple parts. Such a feat is a logical impossibility, and that is why James despaired of resolving the problem of mind within the framework of classical physics. . . The main postulate of the [Heisenberg/James] model is that every conscious event is the psychological counterpart of a certain kind of Heisenberg event in the brain, namely an event that actualizes a pattern of neuronal activity that constitutes a representation of this general kind. However, any such representation must be formed before it can be selected: the representation must be constructed by unconscious brain activity, governed by the preceding mechanical phase of the dynamical evolution before it can be actualized. During this preliminary mechanical phase a superposition of many such representations must inevitably be generated. During the subsequent actualization phase one of these representations will be selected. (Stapp, 1993, p. 24-25)
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