Introduction Dennett (1993) acknowledges consciousness is still a mystery and that his explanation is far from complete. He proposes the Multiple Drafts model of consciousness to replace the metaphor of events in consciousness being witnessed and experienced by an experiencer. The problem with this idea he argues is that there is no one in the brain to observe or feel anything, nor is there anywhere to observe or experience anything. The brain is the mind, there is no consciousness, it only seems like there is such a thing. Dennett introduces the term "phenom" to describe experiences of the external world, the internal world and emotion. He gives the example of stereo sound, how the listener experiences the sound as located somewhere between the two speakers. Heat hazes and glimmers of light are further examples of something in the external world that we "experience" but are an illusion. In our internal world we may see "pictures in the head." But then you would need "eyes" in the brain to look at pictures in the head, and more to look at that picture, ad infinitum. Dennett accepts the inner world is dependent on sensory sources. Sight however, he suggests, so dominates our intellectual practices that we have great difficulty conceiving of an alternative to seeing everything in the mind through the metaphor of vision. Describing affect Dennett gives the example of pain whilst sleeping, or awake, which helps us to make postural corrections to prevent continuous joint abuse. To explain the above phenomena Dennett takes a materialistic perspective and proceeds to consider underlying mechanisms. Back to Top Research Method Although mental events are not the data of science Dennett argues that we can still study them adopting the 'intentional stance.' The person should be treated as a rational agent with beliefs, desires and other mental states that exhibit intentionality or "aboutness" with actions explained or predicted on the basis of the content of these states. If enough real events were found in people's brains with sufficient defining properties of items in their personal world it might be possible to discover what they were really talking about. Dennett suggests creating a catalogue of events, extracting and purifying text to achieve a neutral portrayal of what it is like to be that person, given the best interpretation we can achieve. Back to Top The Multiple Drafts model Dennett describes the stream of mental contents as a narrative stream because at any one point in time there are multiple "drafts" at various stages of editing in various places in the brain. He compares Orwellian "filling in" on the upward path or Stalinesque "memory revision" on the downward post-experiential path and suggests a person cannot tell the difference between visual or memory revision. Thus if you wish to identify the moment of processing in the brain as the moment of consciousness it can only be arbitrary. Dennett gives an example to illustrate his alternative model. Shooting a film does not necessarily follow the storyline. Scenes can be shot out of sequence but then spliced together in the correct order in the cutting room later. Further, and significantly, the actual shooting of a scene, the representing of some event, is one frame of reference. What the representing represents, that is the film story, is another frame of reference. And for Dennett this is what it is for there to be an observer, "...a something it is like something to be." This is the crux of his alternative model. A further example is given of having no memory of having driven the last ten miles. Although this is often described as unconscious perception and intelligent action he argues it is more the case of rolling consciousness with rapid memory loss. He states there are no facts about the stream of consciousness independent of particular probes. (pp.137-138) Back to Top Evolution of Consciousness Dennett explains that the design of our conscious minds is the result of three successive evolutionary processes. First we became selfish with a closed boundary between everything on the inside and everything on the outside: "Me against the World." Next we developed the means to cope with the environment, a way of keeping out of harm's way. Hence brains are effectively anticipation machines, regular vigilance turned into exploration, which led to the birth of curiosity. As the brain evolved further the left/right hemisphere specialization evolved: analytic serial to the left and global, spatiotemporal to the right. Further evolution in brain plasticity enhanced genetic variation. Back to Top Brain Plasticity Flooded with information the need to sustain "trains of thought" led to the evolution of a human mind with the capacity to maintain something like a "stream of consciousness." But Dennett argues, given the remarkable expansion of human mental powers over the last 10,000 years, this is most likely due to harnessing the plasticity of the brain in some radical new way. He proposes something like software to enhance the brains underlying powers and cultural evolution to transmit its products. Through the evolution of language it can be speculated that vocalization led to entirely silent talking to oneself; then the drawing of pictures and other useful modes of self-stimulation. Developing a personal style with particular strengths and weaknesses, good enough for the majority of people to get by in the civilised world, reduces the selection pressure for further genetic evolution. Back to Top Memes, Cultural Evolution and Consciousness After adjusting to local conditions and acquiring language skills our brains are said to become parasitised by memes. Citing Dawkins, memes are described as "replicators," a complex of ideas, identifiable as cultural units, that leap from brain to brain via imitation. These ideas establish a functional architecture that Dennett equates to "software levels." He suggests we need to understand how, through training, human consciousness can be realised in the operation of a [serial] virtual machine created by memes in the [parallel] architecture of the brain. To this end Dennett sets out his hypothesis. (p.219) Human consciousness; is too recent an innovation to be hard-wired into the innate machinery; is largely a product of cultural evolution that gets imparted to brains in early training, and its successful installation is determined by myriad microsettings in the plasticity of the brain (hence its functionally important features are very likely to be invisible to neuroanatomical scrutiny) His question: If consciousness is a virtual machine who is the user for whom the illusion works? Dennett reminds us, citing Margolis, that because the immediate contents of the stream of consciousness are very quickly lost we rehearse interim results to commit them to memory. The computer on the otherhand is entirely unconscious because from the very start it was made with maximally efficient informational links. It didn't have to become the object of its own elaborate perceptual systems. Back to Top Architecture of the human Mind Dennett argues that there is no single "stream of consciousness" because there is no central headquarters where "it all comes together" for the perusal of a Central Meaner. Instead there are multiple channels in which specialists try, in parallel pandemoniums to do their various things, creating Multiple Drafts as they go. The seriality of this machine is not a "hard-wired" design feature, but rather the upshot of a succession of coalitions of these specialists. Dennett continues relating views from neuroscience, cognitive psychology and Artificial Intelligence (AI) to his basic hypothesis. From AI research into parallel processing he asks the question : How do such systems deal with conflict resolution? There is a gathering consensus for the idea of a global workspace where just about everything can keep in touch with everything else. However, the same neural tracts and networks involved in the global workspace also play a major role in long-term memory. Dennett then asks the question: How can these two very different sorts of representation coexist in the same medium at the same time? Such multiple, superimposed functionality is difficult to discern from the perspective of reverse engineering. Back to Top Powers of a Joycean Machine The idea is that there is competition among many concurrent events in the brain and a select subset of such events "win." Dennett argues it is a risky oversimplification to ask "what is the purpose of consciousness?" we assume that there is a single "information-processing task." This overlooks the fact that some features of consciousness have multiple functions and some no benefit at all. When a task is difficult or unpleasant, it requires "concentration," something that "we" accomplish using mental strategies and talking to oneself. Rehearsal for instance creates a memory of the route by which we have arrived at where we are and if stuck what errors we have made in getting there. Citing both Dreyfus and Searle, the importance of a "background" of conscious experience that might be related to some sort of "intrinsic intentionality" is suggested. However, citing Gulick, it is argued there is no distinct substantial self who somehow produces connections between subpersonal components. Back to Top A Theory of Consciousness Dennett accepts that consciousness is, intuitively, something special. However, he argues that he has shown many of the presumed powers of consciousness could be explained by the powers of the Joycean machine whether or not it endows its host hardware with consciousness. Couldn't, he asks, '...there be an unconscious being with an internal global workspace in which demons broadcast messages to demons, forming coalitions and all the rest? If so, then the stunning human power of swift, versatile adjustment of mental state in response to almost any contingency, however novel, owes nothing to consciousness itself, but just to the computational architecture that makes this intercommunication possible.' If so, he argues, anyone or anything that has such a virtual machine as its control system is conscious in the fullest sense, and is conscious because it has such a virtual machine. (pp.280-281) Back to Top Philosophical problems of Consciousness Dennett begins by identifying the limitations in our ability to visualise and manipulate mental images. However, to overcome this we use diagrams, graphs or maps as re-presentations of the information—not to an inner eye but to an inner pattern recognition mechanism— so that sought-for regularities and saliencies just "pop-out" at us, thanks to our visual systems. They can also help us to keep track of what is relevant, and remind us to ask the right questions at the right times. Dennett suggests that those in whom these skills are highly developed have different virtual machines in their brains and the differences emerge in their heterophenomenological worlds. Language structure is said to enforce a discipline on our habits of thought. This would not make sense unless we stop thinking of the mind as ideally rational or unified. Dennett gives the example of how saying words to yourself can kindle reactions and warns us to be careful what we say to ourselves! He continues by noting the difference between us and robots. We are said to be constantly rebuilding ourselves, discovering new things to say as a result of reflecting on what we have found ourselves wanting to say. Dennett explains that just as most computer-users do not understand the machine code below the user interface (e.g. MS Windows®) we do not understand how the backstage machinery of our brains works. But this begs the question: How can there be a User Illusion without this separation? What we need to do is explain not that our are organised into hierarchies of higher-ordered representational "states" of belief, meta-belief, and so on, but that our minds seem to us to be ordered this way. Back to Top Further Objections Intuitively we have a sense that for real understanding to occur there has to be someone to witness the events whose happening constitutes the understanding. For Descartes, the witness was the Soul. Dennett considers the phenomenon of Blindsight by which it is claimed that totally blind persons can detect movement of light across the visual field. However, it is noted that subjects are prompted and through practice might develop a talent for guessing when to guess rather than actually detecting any movement of light. Further examples are given; the apprentice piano tuner whose conscious experience is changed as a result of training. Although "beats" could be heard prior to training there was no conscious awareness of them; "Filling in" of the blind spot; a reading experiment that demonstrates (due to muscle contractions that move the eyes) that words on a screen cannot be seen. The point Dennett is making with these examples is that something seems to be there that isn't or vice versa. Thus he argues that there is nothing beyond judging in one way or another that something is the case. There are many judgements around in time and space in the brain but there is no one Discerner doing all the work. He concludes it is all "as if". Therefore the idea of a Self or the Soul is an abstraction, but an exquisitely useful fiction, just like consciousness. Back to Top Qualia dismissed Dennett next moves to dismiss qualia, secondary qualities such as colour, the way things look, sound or smell as opposed to primary qualities such as shape and size. He asks how can qualia just be just something physical happening in my brain? He suggests the richness we marvel at is actually the richness of the world outside, it does not enter our conscious minds, it is simply available. The joy we feel cannot be explained by the invocation of intrinsically pleasant qualia or sight, sound and sheer thought. We should look for a description of the underlying mechanisms and an explanation (ultimately an evolutionary explanation) of why the mechanisms do what they do. All visual experience is composed of the activities of neural circuits whose very activity is innately pleasing to us, not only because we simply like to become informed but because we like the particular ways we come to be informed. This is just the way we are. Our existence is explained by the fact that there are these capacities in our bodies. The idea is of a self that is the Centre of Narrative Gravity. Back to Top The Reality of Selves This psychological or narrative self is an abstraction, not a thing in the brain. Citing Paul Valéry "Sometimes I am, sometimes I think." The only "momentum" that accrues to the trajectory of a self, or a club, is the stability imparted to it by the web of beliefs that constitute it, and when those beliefs lapse, it lapses, either permanently or temporarily. An advanced agent must build up practices for keeping track of both its bodily and "mental" circumstances. Thus we do build up a defining story about ourselves, organised around a sort of basic blip of self-representation. If you think as yourself as a centre of narrative gravity your existence depends on the persistence of that narrative. Back to Top In Conclusion Dennett claims that he has explained the phenomenon of human consciousness in terms of the operations of a "virtual machine," a sort of evolving computer program that shapes the activities of the brain. There are said to be Multiple Drafts that play various semi-independent roles in the brains larger economy of managing the human body's journey through life. "Qualia" are described as complex dispositional states of the brain and the Self is the Centre of Narrative Gravity, nothing more than a valuable abstraction, a theorist's fiction rather than an internal observer or boss. Back to Top