For all its utility and mysterious complexity, consciousness is full of defects. The common sense view - largely unchallenged throughout our history -- is that consciousness presents us with a picture of how things are "out there" that we are able to view "inside" our minds. Philosophers have called this view the "Cartesian Theatre:" the experience of viewing the world in our minds presupposes a division, on the one hand, between the materialistic world of real objects that have substance and weight and, on the other, the inner, non-materialistic mind that constructs representations of those objects and reacts. This dualism no longer sits comfortably with most scientists and philosophers. Moreover, the philosophical dilemma of dualism leads us to two highly practical problems: misleading appearances of coherence in the world and illusions of agency in the self.
First off, the picture we view in our "Cartesian Theatre" imposes a false unity on our experience. We see a coherent world, seemingly available for scrutiny and systematic thought, but that world does not actually map onto reality. This is the "user illusion," as it has sometimes been called, based on the analogy of our relationship with our computers where we interface with pictures and programs, not the thing itself. As Edelman has put it: "The take-home lesson is that our body, our brain, and our consciousness did not evolve to yield a scientific picture of the world."
Damasio has endorsed Dennett's "Multiple Drafts" model of consciousness to reflect the complexity of how consciousness is actually constructed. Our experience, in the "Cartesian Theatre," presents a simple and coherent view of the world because the multiple drafts of reality have been invisibly edited and synthesized. We are unaware of the machinery that goes into its construction. In order to present coherent messages suitable for action, vast stores of information that cannot be processed are discarded. Moreover, what is missing, the gaps, are filled in by inference or memory. What we experience consciously, in other words, is a simulation, a fiction.
Psychologists refer to "accessibility" to describe what gets included in the final edit, but many factors enter into the accessibility of information: how recent and how frequent our exposure to it has been, how relevant it is to the actions we are considering, how frequently it has been used in the past, how it makes us feel. This latter point accounts for the relative ease with which information that makes us uncomfortable or that does not accord with our idealized versions of ourselves tends to be discarded. As the psychologist Timothy Wilson has put it: "We are masterly spin doctors, rationalizers, and justifiers of threatening information."
Dramatic examples of such editing are described in the research on "split brains," where neurosurgeons have severed the connections between the left and right hemispheres in order to prevent epileptic seizures. Joseph LeDoux, describing this research, noted that patients inevitably compensated for what they did not understand about their own behavior: "Time after time, the left hemisphere made up explanations as if it knew why the response was performed. For example, if we instructed the right hemisphere to wave, the patient would wave. When we asked him why he was waving, he said he thought he saw someone he knew." The lesson is that, however impaired, the brain does not cease its sometimes heroic efforts to impose unity and coherence on the information it processes.
The second set of illusions has to do with agency. Consciousness fosters the belief that we are in charge of our actions, but the evidence of neurobiology suggests that most of our decisions are made automatically. Our reactions to events are underway before we become aware of them. As Freeman has put it: "taking responsibility for one's self is more like trying to control one's teenager than one's automobile.
Sometimes, of course, it is obvious that making something conscious impedes our reactions to events. LeDoux has noted that "prepackaged emotions" quickly elicit reactions to danger that aid survival, a point that Darwin also made. If we see a stick that moves, our bodies do not stop to figure out if it is a snake before starting to flee.
Indeed, our brains often embark on actions or construe reactions to events without our needing to know what we are doing. Almost fifty years ago, Michael Polyanyi pointed out the importance of "tacit knowledge," knowledge we take for granted. When we recognize familiar faces, for example, we rely upon such knowledge without knowing we possess it. More recently, psychologists have distinguished between "implicit" and "explicit" memory, highlighting the importance in our daily lives of the information we process subliminally, without consciousness. Similarly, they have studied "procedural memory," the built-in sets of perceptions and skills that are required for riding a bicycle or driving a car.
But many have argued more broadly that these are merely particular instances of a general truth: consciousness always arises after the fact of perception and response. Freeman notes that awareness "continually runs to catch up with the self, half a second late but backdated." Damasio puts it this way: "We are always hopelessly late for consciousness and because we all suffer from the same tardiness no one notices it." In other words consciousness arises from the information we have received, the interpretations we have constructed, and the decisions we have already made. Our bodies and brains have processed that information and constructed a response that is already set in motion when we become aware of it. The evolutionary value of consciousness turns out to be, from this perspective, not in the capacity it provides for us to decide on our actions in advance so much as the opportunity to reflect on the world we perceive and plan new courses of action, after the fact. With it, we can inhibit or alter our behavior, and we can plan better responses for the future. As Damasio put it in the passage quoted earlier, the evolutionary benefit is "forethought."
Ken Eisold is a psychoanalyst and organizational consultant who has written What You Don't Know You Know, a book that expands our understanding of the unconscious to include organizations, politics, economics, and public affairs. He comments regularly on current events on his blog: http://www.keneisold.com
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