The mere fact that such a familiar feature of our lives has resisted for so long all attempts to characterize it suggests that our conception of it is at fault. What is needed is not just more evidence, more experimental and clinical data, but a careful rethinking of the assumptions that lead us to suppose there is a single and familiar phenomenon, consciousness, answering to all the descriptions licensed by our everyday sense of the term. Consider the baffling questions that are inevitably raised whenever one turns one’s attention to consciousness. Are other animals conscious? Are they conscious in the same way we are? Could a computer or a robot be conscious? Can a person have unconscious thoughts? Unconscious pains or sensations or perceptions? Is a baby conscious at or before birth? Are we conscious when we dream? Might a human being harbor more than one conscious subject or ego or agent within one brain? Good answers to these questions certainly will depend heavily on empirical discoveries about the behavioural capacities and internal circumstances of the various problematic candidates for consciousness, but about every such empirical finding we can ask: what is its bearing on the question of consciousness and why? These are not directly empirical questions but rather conceptual ones, which we may be able to answer with the help of thought experiments.
Our ordinary concept of consciousness seems to be anchored to two separable sets of considerations that can be captured roughly by the phrases “from the inside” and “from the outside.” From the inside, our own consciousness seems obvious and pervasive, we know that much goes on around us and even inside our bodies of which we are entirely unaware or unconscious, but nothing could be more intimately know to us than those things of which we are, individually, conscious. Those things of which I am conscious, and the ways in which I am conscious of them, determine what it is like to be me. I know in a way no other could know what it is like to be me. From the inside, consciousness seems to be an all-or-nothing phenomenon—an inner light that is either on or off. We grant that we are sometimes drowsy or inattentive, or asleep, and on occasion we even enjoy abnormally heightened consciousness, but when we are conscious, that we are conscious is not a fact that admits of degrees. There is a perspective, then, from which consciousness seems to be a feature that sunders the universe into two strikingly different kinds of things, those that have it and those that don’t. Those that have it are subjects, beings to whom things can be one way or another, beings it is like something to be. It is not like anything at all to be a brick or a pocket calculator or an apple. These things have insides, but not the right sort of insides—no inner life, no point of view. It is certainly like something to be me (Something I know “from the inside”) and almost certainly like something to be you (for you have told me, most convincingly, that it is the same with you), and probably like something to be a dog or a dolphin (if only they could tell us!) and maybe even like something to be a spider.
When one considers these others (other folk and other creatures), one considers them perforce from the outside, and then various of their observable features strike us as relevant to the question of their consciousness. Creatures react appropriately to events within the scope of their senses; they recognize things, avoid painful experiences, learn, plan, and solve problems. They exhibit intelligence. But putting matter this way might be held to prejudge the issue. Talking of their “senses” or of “painful” circumstances, for instance suggests that we have already settled the issue of consciousness—for note that had we described a robot in those terms, the polemical intent of the choice of words would have been obvious (and resisted by many). How do creatures differ from robots, real or imagined? By being organically and biologically similar to us—and we are the paradigmatic conscious creatures. This similarity admits of degrees, of course, and one’s intuitions about what sorts of similarity count are probably untrustworthy. Dolphins’ fishiness subtracts from our conviction that they are conscious like us, but no doubt should not. Were chimpanzees as dull as seaslugs, their facial similarity to us would no doubt nevertheless favour their inclusion in the charmed circle. If houseflies were about our size, or warmblooded, we’d be much more confident that when we plucked off their wings they felt pain (our sort of pain, the kind that matters). What makes us think that some such considerations ought to count and not others?
The obvious answer is that the various “outside” indicators are more or less reliable signs or symptoms of the presence of that whatever-it-is each conscious subject knows from the inside. But how could this be confirmed? This is the notorious “problem of other minds.” In one’s own case, it seems, one can directly observe the coincidence of one’s inner life with one’s outwardly observable behaviour. But if each of us is to advance rigorously beyond solipsism, we must be able to do something apparently impossible: confirm the coincidence of inner and outer in others. Their telling us of the coincidence in their own cases will not do, officially, for that gives us just more coincidence of outer with outer; the demonstrable capacities for perception and intelligent action normally go hand-in-hand with the capacity to talk, and particularly to make “introspective” reports. If a cleverly designed robot could (seem to) tell us of its inner life, (could utter all the appropriate noises in the appropriate contexts), would we be right to admit it to the charmed circle? We might be, but how could we ever tell we were not being fooled? Here the question seems to be; is that special inner light really turned on, or is there nothing but darkness inside? And this question looks unanswerable. So perhaps we have taken a misstep already.
My use of “we” and “our” in the last few paragraphs, and your unworried acceptance of it, reveals that we don’t take the problem of other minds seriously—at least for ourselves and the human beings with whom we normally associate. It is tempting to conclude that insofar as there is a serious question yet to be answered about the imagined robot (or about some problematic creature) it must turn out to be answerable by straightforward observation. Some theorists think that once we have better theories of the organization of our brains and their role in controlling our behaviour, we will be able to use those theories to distinguish conscious entities from nonconscious entities. This is to suppose that somehow or other the facts we get individually “from the inside” reduce to facts publicly obtainable from the outside. Enough of the right sort of outside facts will settle the question of whether or not some creature is conscious. For instance, consider neurophysiologist E.R. John’s[1] recent attempt to define consciousness in objective terms.
.. a process in which information about multiple individual modalities of sensation and perception is combined into a unified multidimensional representation of the state of the system and its environment, and integrated with information about memories and the needs of the organism, generating emotional reactions and programs of behaviour to adjust the organism to its environment.
Determining that this hypothetical internal process occurs in a particular organism is presumably a difficult but empirical task in the province of a new science of neural information processing. Suppose that with regard to some creature it were completed successfully; the creature is, by this account, conscious. If we have understood the proposal correctly, we will not find any room to wonder further. Reserving judgment here would be like being shown in detail the operations of an automobile engine, and then asking, “But is it really an internal combustion engine? Might we not be deluded in thinking it was?
1
For additional information on the authors and the works cited in the text, consult “Further Reading” beginning on p. 465.