A Role For Consciousness
David Hodgson pulls together his experience to understand experience.
One of the great enduring mysteries of science lies in the question What does consciousness do? Or more specifically, What if anything is achieved by subjective conscious experiences, such as visual and auditory experiences, conscious thoughts, and feelings such as pain and hunger, that is not achieved by physical brain processes unfolding in accordance with physical laws of nature?
Many scientists and philosophers would answer nothing. According to them, the physical world operates in accordance with the laws of physics, chemistry and biology, and is closed to being affected by anything non-physical. Thus, any effects that conscious experiences may have can only come about by virtue of physical brain processes that are associated with and perhaps constitute these experiences.
This physicalist approach, however, raises a question. If everything is achieved by physical processes operating in accordance with physical laws, why are some of these processes associated with subjective conscious experiences, when this association does precisely nothing? From an evolutionary viewpoint, this would not seem to make sense: the selection of consciousness through the survival and reproduction of conscious organisms strongly suggests that consciousness confers an advantage on an organism that has it.
A possible answer is that somehow conscious experiences are inevitably associated with certain advantageous physical processes, so that when these advantageous processes were selected in evolution, consciousness was selected with them. Just as, for example, a polar bear can’t have the useful warmth of its coat without its non-useful weight, we can’t have some kinds of useful operations carried out by brains without the non-useful conscious experiences.
However, nothing remotely plausible has ever been suggested as to why this should be so. Indeed, the best suggestions offered by physicalists as to why the brain processes associated with conscious experiences are advantageous, are to the effect that they carry out useful information-processing – which is just what can be done, without consciousness, by a computer. This has led some physicalists to suggest that consciousness is a kind of fiction, or alternatively that computers are (or with more processing power will become) conscious. But these suggestions are, I suggest, highly unlikely to be true. There are some scientists and philosophers who oppose the physicalist view, and who argue on evolutionary and other grounds that consciousness itself must have an advantageous role. Surprisingly, though, there is a dearth of suggestions from them too as to a plausible role for consciousness.
I want to offer a specific and straightforward proposal as to what the role of consciousness is:
Consciousness enables an organism to respond to circumstances grasped as wholes, not just to constituent features that can engage with laws or rules of computation.
To expand a little:
The evolutionary advantage of consciousness is that it enables an organism to determine and/or shape a response to circumstances facing it that has regard, not only to features that can engage with laws of nature and/or computational rules, but also to whole combinations of features that are particular and perhaps unique to the circumstances and cannot as wholes engage with laws or rules.
Subjectivity, Qualia and Unity
My suggested role takes account of three striking and puzzling features of conscious experiences: subjectivity, qualia and unity.
First, subjectivity. Conscious experiences are experiences had ‘from the inside’ by a conscious subject. They are not like objective features of the world, equally available for observation by anyone in a position to observe them. Other people may know that I am in pain, but only I feel my pain. Conscious experiences are part of a subject’s take on the world; and it is reasonable to think that these experiences contribute to the subject ’s response to the world.
Second, qualia. Conscious experiences have features or qualities that go beyond the physical processes that seem to cause them: the look of colours, the feel of pain, and so on. These features have been called qualia. For example, there seems to be nothing about the wavelengths of electromagnetic radiation, or the physical brain processes caused by visually encountering them, that captures or explains the actual look of a blue sky. Although a computer can display blue on its screen, there is no reason to think a computer actually experiences the colour blue or knows what the colour blue looks like.
Third, unity. A conscious experience is a unity in the sense that many features are experienced all-at-once by the subject. This is particularly striking in the case of visual experiences, in which a subject is aware of many features of an observed scene, and generally grasps them all-at-once in a unified experience or ‘gestalt’. How this happens when different features such as shapes and colours are processed by different parts of the brain is itself a mystery, which has been called the binding problem of consciousness. Again, while a computer can process features of information it has by operations determined by computational rules, there is no reason to think that it can grasp combinations of features as whole gestalts.
Laws, Rules and Gestalts
I need to say a bit more about features that can engage with laws of nature and/or computational rules, and combinations of features that cannot as wholes engage with them.
It is characteristic of laws and rules that they apply generally over a range of circumstances. They must engage with types or classes of features that different circumstances have in common, or with variable quantities in the case of mathematical rules. So while laws and rules can apply to individual unique circumstances, they engage with features of these circumstances only in so far as each of these features is of a type or class, and/or is a variable quantity.
Circumstances encountered and perceived by living organisms do have constituent features that are common to different circumstances, and thus could be features that engage with laws or rules. Even simple qualia, had in common by different subjects or by the same subject at different times, could do so. However, each set of circumstances also has combinations of features that are not of a type or class but are particular and perhaps unique to that set of circumstances; and except to the extent that these combinations of features might be adequately represented as wholes in terms of types and mathematical variables, they cannot as wholes engage with laws or rules.
When a conscious organism such as a human being experiences some set of circumstances, features of what is experienced are combined into unified gestalts, such as visual experiences combining many features of an observed scene. I have argued in detail elsewhere that since these feature-rich experiences are combinations of qualia, they can’t be adequately represented in terms of types and mathematical variables; and since they are particular and perhaps unique combinations of features, they can ’t as wholes engage with laws or rules. My suggestion is that, although these gestalts cannot as wholes engage with laws or rules of any kind, they may plausibly as wholes make a contribution to our decisions, because we can respond to them.
There are of course unconscious computational processes of our brains that do engage with constituent features of what we experience (or with representations of them) in terms of types and mathematical variables. These processes are essential to our having conscious experiences at all, and are essential in other ways to our decisions and actions. But I suggest there is in addition, in our conscious decision-making and action, a contribution from our grasping whole combinations of features; and since this response can ’t be determined by laws or rules, it isn’t one that could be achieved by non-conscious information-processing.
My suggestion is that the capacity to respond in this way to particular and perhaps unique combinations of circumstances is advantageous, even though it must also be fallible because its reliability is not assured by any rules or laws. This advantage explains why consciousness has been promoted by evolutionary processes.
George Gershwin Gestalts
An example I sometimes give is that of George Gershwin composing his melody ‘The Man I Love’. This melody has both general and quantitative features in common with other melodies. These features, being general and quantitative, can engage with general rules, so that the melody could readily be identified by applying computational rules. No doubt such an appealing melody has constituent features that can push buttons in our emotional make-up that have been established by evolution and environment. But the way the melody sounds, and even the way some two- and four-bar chunks of it sound, is unique to this melody; and the experience of such a unique melody or chunk of melody, as a whole, is an example of what I mean by a gestalt that cannot engage with laws or rules.
When Gershwin was composing the melody, possibilities for how it should proceed must have been thrown up by unconscious processes. But he also must have consciously appraised these possibilities as he composed, to decide whether to adopt them, modify them or look for other possibilities. Ultimately he must have consciously appraised the melody itself, to decide whether to assent to it as his final composition or to refine it further. I suggest that in appraising the possibilities and the melody, Gershwin was responding to gestalts of the possibilities and of the melody, which because of their uniqueness and feature-richness could not engage as wholes with pre-existing rules of any kind.
The same argument applies with even greater force to the creation of ground-breaking works that defy existing aesthetic standards, such as Wagner ’s Tristan und Isolde or Picasso’s Les Demoiselles d’Avignon. The creation of works like these requires aesthetic judgments to be made by the creators, which must take account of whole gestalts that could not engage with pre-existing laws or rules of any kind.
I suggest that the argument also applies to human decision-making generally, whenever we take account of whole feature-rich gestalt experiences in shaping our decisions and actions.
I can’t explain how we can respond to gestalts in ways not determined by rules – this would require a far greater understanding of consciousness than is available at present – but that we can do so is supported by the very fact that we do experience whole feature-rich gestalts ‘all-at-once’, and by many other reasons. Here are a few.
Any decision or action that can be determined by the operation of general rules on existing circumstances can be determined by computation, without consciousness: this seems obvious, and it is confirmed by Alan Turing’s arguments, and by the existence and performance of computers. Our brains do undoubtedly have a prodigious capacity for unconscious computations. Think for example of the computations necessary to give us three-dimensional vision, with stability of viewed scenes despite voluntary movements of head and eyes, or those necessary to enable us to balance and to catch balls. Though most of us can’t plug directly into this computing power, there are reports of people who have done so, not necessarily to their advantage: in his book The Man Who Mistook His Wife For a Hat, for example, Oliver Sacks wrote about autistic twins who enjoyed exchanging multi-digit prime numbers. If optimal decisions could be made by computations alone, why do we have our clumsy, fallible conscious processes at all?
The fact is that conscious experiences are heavily involved in our decisions, particularly when we are faced with a novel situation requiring some significant decision or action. Much unconscious information processing seems to be finely tuned to support conscious experiences, in which currently important information is presented simply and vividly, in the manner of an executive summary prepared for a decision-maker in business or government. The computer scientist Marvin Minsky once dismissed consciousness as an imperfect summary of what is going on in the brain; but he failed to recognize that there must be an evolutionary advantage in having this summary. Surely, we have these executive summaries just because we can respond to them in ways not available to unconscious computation; that is, in ways not determined by laws or rules.
I contend that one important way in which we use and respond to gestalt experiences is in plausible reasoning. Most human reasoning is not algorithmic: that is, it does not (overtly at least) proceed in accordance with rules of logic, mathematics or probability, or any other rules that could be incorporated into a computer program. Rather, it is informal, plausible reasoning, in which the premisses or data do not entail the conclusions by virtue of applicable rules, but rather support them as a matter of reasonable judgment. Arguments of Hume, Popper and others, particularly as developed by the American philosopher Hilary Putnam, show that plausible reasoning cannot be fully explained in terms of rules for good reasoning, whether they be rules of logic or mathematics or probability or whatever.
Consistently with this, consciously held reasons for decisions and actions are often inconclusive. There is an apparent gap between reasons on the one hand and decisions and actions on the other. Hume said we always act in accordance with the preponderance of our desires. But that assumes that desires, like forces in Newtonian physics, are commensurable (i.e. are of types that can mix together), so that there is always a single ‘resultant’ desire that can direct our decisions and actions; whereas in truth there is no common scale on which (say) a feeling of hunger can be explicitly weighed against a feeling of obligation to carry out a promised task. If desires conflict, the outcome is not determined by any overt preponderance of one over the other (there can be no preponderance of incommensurables because they cannot be compared), but by plausible reasoning to a decision that takes account of their different characters. In this plausible reasoning we use and respond to gestalt experiences.
Of course plausible reasoning is fallible and, as Daniel Kahneman, Amos Tversky and others have shown, it is affected by unconscious biases. But plausible reasoning is indispensable, and biases can be addressed and their effect minimized only by careful conscious appreciation of them, that is, by plausible reasoning – certainly not by leaving it to the unconscious computational processes that are the source of the biases.
My proposal thus offers an explanation of why conscious experiences enable us to live more successfully than if our decisions and actions were determined by unconscious processes alone. It gives a function to the three most striking puzzles about conscious experiences: subjectivity, qualia and unity. And as I have argued elsewhere, it also opens the way to a robust account of free will and responsibility.
Conflict with Science?
It’s been put to me that my proposal is courageous, in the Yes Minister sense, in that by suggesting that the physical world is open to non-physical influences, it conflicts with well-established science. Well, it does conflict with Newtonian physics, as interpreted by Pierre Laplace. But science has moved on since the nineteenth century; and while quantum mechanics supports randomness rather than indeterministic choice, it plainly leaves it open that physical events may be affected by conscious experiences and choices.
These are large and difficult questions, and I cannot explore them here. What I do say is that the reasons supporting my proposal are strong, and the correct understanding of fundamental science is unclear. If conscious experiences are truly efficacious, as I suggest they must be, the reasons for thinking they have this efficacy only by virtue of physical processes and physical laws are not compelling. Thus my proposal is a plausible one, indeed so far as I’m aware the only plausible proposal there is for assigning a specific role for conscious experiences that could not be performed by unconscious processes.
Has anyone got a better suggestion?
© David Hodgson 2008
David Hodgson is a Judge of the Supreme Court of New South Wales. He is the author of Consequences of Utilitarianism (1967) and The Mind Matters (1991), both published by OUP, and of numerous philosophical articles, a selection of which can be found at users.tpg.com.au/raeda.