Consciousness is, in one way, the easiest and most obvious thing in the world to understand, for anyone capable of thinking about it is intimately conscious of being conscious – we live with our noses pressed hard up against our own consciousness, which attends every moment of our aware experience and thought; and similarly, the consciousness of others is lambent in their faces and behaviour, and we each have a rich and highly nuanced knowledge of how to read and respond to those lambencies. Their presence and our understanding of them constitute the ordinary stuff of everyday social interaction.
At the same time, consciousness is by far the most perplexing mystery facing philosophy and the neurological sciences. It is such a difficult problem that for a long time philosophers put off thinking about it, and scientists ignored it entirely. Some, in the tradition of Descartes, still think that it is too hard for human intelligence; they say that the human brain is not made to understand itself. Others even claim that there is no such thing as consciousness; we are actually zombies, just very complicated ones. In defiance of these (variously pessimistic and silly) views, most students of the problem – philosophers, neuroscientists and psychologists, working in concert – have taken advantage of the availability of powerful new investigative tools, especially brain-scanning devices (CAT, PET and MR scans) , to watch both healthy and damaged brains actually at work in the processes of learning, sensing, remembering, reasoning and feeling. One result has been a massive increase in our knowledge of brain function, in particular a refined understanding of the correlation between specific brain areas and specific mental capacities. Aristotle thought that the brain was a device for cooling the blood (after all, you wear a hat to keep warm in winter), and that the seat of the mind was the heart (where, when you see the beloved, tumult occurs); if nothing else, recent science has settled conclusively what everyone since Aristotle has believed to the contrary.
But all this knowledge does not amount to an understanding of consciousness, which is far too protean and varied a phenomenon for simple matchings between conscious states and activity in this or that brain-structure. Above all, no degree of accuracy in tracing a given mental event to a given brain event can by itself explain how coloured pictures, evocative smells and harmonious or discordant sounds arise like a (scented) cinema-show in the head. This is the central problem of consciousness, and this is what Antonio Damasio addresses in this fascinating and suggestive book.
For Damasio, consciousness begins as a special kind of feeling: the feeling of feeling. This constitutes a primitive level of selfhood, a powerful but vague awareness of occupying what we later call a first-person perspective. The self and its objects – the things that cause emotional responses in the self- come to constitute a relational -model of the world; at this point consciousness is not just a feeling of feeling, but a feeling of knowing. Describing the roots of consciousness in terms of feeling allows us, says Damasio, to explain the central phenomenon of consciousness: the sense that we are each the owner and viewer of a movie-within-the-brain that is our own aware experience, and which represents to us a world of which we are the centre.
Put in this sketch form, the theory does not seem especially illuminating; but it is the details of Damasio’s use of brain science and clinical neurology – the study of healthy and diseased brains and what they respectively can and cannot do in the way of human tasks – that provides the meat in the sandwich. For a prime example: one thing that struck Damasio was the fact that some patients can be awake and, to a degree, aware of their surroundings and able to interact with them, yet in non-conscious ways; showing that consciousness is not the same thing as mere awakeness or awareness. The extra faculty that is consciousness must have survival advantage, otherwise higher mammals would not have evolved it; Damasio suggests that the appropriate utilisation of energy, and the protection of the organism from harm, which are the chief goals of any living creature, are much enhanced by an organism’s being able to place itself in a map of the environment, and to make plans and judgements about the best courses of action in relation to it. Creatures that are automata – though aware and highly sensitive to their environment – might do this well enough, but not as well as creatures who are truly conscious.
Damasio bases his case upon evidence from neuropsychological data showing that specific parts of the brain correlate to specific mental capacities, that there are different levels of consciousness and that a lot of mental ‘processing’ happens at non-conscious levels, and that consciousness is not one but many things. On this foundation he distinguishes between ‘core consciousness’, with its primitive sense of self, and the higher-level phenomena of ‘extended consciousness’ and its subject, the ‘autobiographical self’. Using these notions he argues that consciousness is not to be understood simply in terms of other cognitive functions like language, memory, reason and attention, although it crucially involves them; for although these functions presuppose consciousness, they do not constitute it.
An intriguing aspect of Damasio’s work in the past, which has become a persuasive element in his theory here, is that emotions are fundamental to both consciousness and reason. Deficits of consciousness in brain-damaged patients are always accompanied by deficits in emotional capability. Damasio also discovered that brain damage which destroys the capacity to feel certain emotions results in impaired reasoning too; just as too much emotion interferes with logic, so does too little. But it is the point about the direct relation of emotion to consciousness that is most intriguing in this book; for in locating the origins of the whole charivari of consciousness in feelings, Damasio is saying that emotion lies at the basis of thought and personal identity. Even though, at the end, he says that the questions ‘what are feelings? What are feelings the perception of?’ have yet to be answered, one has the feeling that he may be on the right track.