Enchanted Looms is a detailed and adept attempt to deal with the contentious core of the mind/body problem, namely, consciousness, within the broad framework of a computational approach, as suggested by the subtitle, Conscious Networks in Brains and Computers. Rodney Cotterill believes that ‘consciousness is fast becoming one of the last major bastions of mystery.’ (p. xi) and his aim is to solve the mystery. For Cotterill, the justification for delving into such matters substantially stems from the ‘ultimate need to judge whether conscious computers are likely to emerge in the foreseeable future.’ (p. 172)

The book contains eleven chapters, which could be divided into three parts. Part one consists of Chapters 1 and 2 where Cotterill offers an overall view of the project, its problems and the history of mind in terms of its physics. The second part covers Chapters 3 to 8, which describe the cortical anatomy and neurophysiology of brain in great details with an emphasis on how a computational theory could be used to explain cerebral activities. Concerning the latter, however, Cotterill is insistent on distinguishing between computational constructions inspired by the brain and the actual neuronal networks present in the brain, where it is the latter that one should aim for in the quest for understanding consciousness. Finally, Chapters 9 to 11 form the third part in which Cotterill attempts to explain the emergence and functioning of a range of mental phenomena such as sensation, thought, emotion, intelligence, introspection, and language from a neurological-cum-philosophical perspective.

Cotterill is one of the leading researchers in the field with an expertise in biophysics, and naturally his empirical background heavily informs his approach to the question of consciousness. His account could, therefore, be embedded within the camp of constructive naturalism, according to which consciousness is a purely natural phenomenon and its explanation must be solely constructed in terms of physical notions and concepts. In this spirit, Cotterill develops a scientific approach to consciousness by linking conscious experience to observations from neuroscience and cortical anatomy about correlated brain activity and function, and to the descriptions of mental processing that come from psychology and cognitive science. A characteristic feature of Cotterill’s naturalistic approach is its bottom-up strategy, whereby the aim is to synthesize a multi-cellular picture from the available knowledge of how individual nerve cells behave. (p. 29) That is, to present an explanation of conscious phenomena in terms of the underlying processes at the neuronal level. Whereas a top-down route takes its starting point observations on the behavior of the complete person and uses these to draw conclusions about the nature of the underlying mechanisms. Although Cotterill agrees that a full and complete explanation should include both strategies (p. 321), he insists that a proper appreciation of the top-down route could be obtained only through prior consideration of what the bottom-up strategy is able to offer. From a philosophical perspective, however, the merit of Cotterill’s work lies in its sensitivity to and concern for issues surrounding consciousness in philosophy.

Obviously, the first port of call in the quest for a constructive account of consciousness is to give a delineation of what one is looking for, viz., ‘what consciousness actually is.’ (p. 9) However, as Cotterill concedes and most other researchers in the field readily attest, the concept has turned out to be very elusive and hard to elucidate. Nonetheless, Cotterill offers an interesting diagnosis for the difficulty to pin down the ‘bare essentials’ of consciousness: it is the failure to separate consciousness from its products. Cotterill contends that the elusiveness emerges from the sheer abundance of mental and experiential phenomena mediated by consciousness, which has eclipsed the nature of this fundamental attribute. On his reading, one must differentiate between the underlying mechanism of consciousness and its mere consequences, i.e., ‘the tall and richly varied oaks of our conscious experiences and the little acorn of the underlying mechanism.’ (p. 332) Cotterill thus proposes that ‘it is the mind that is the product of consciousness.’ (p. 10; original emphasis)

With this ontological reversal and in pursuit of exposing the bare essentials of consciousness, Cotterill adopts a paradoxically “refreshing” approach by appealing to some of the old and somewhat defunct modes of thinking about the mind, in particular, behaviorism and motor theory of mind. Within the constructive naturalist camp, Cotterill is espousing a type of neo-behaviorism – he in fact calls it quasi-behaviorism. (p. 344) According to classical behaviorism, there was nothing over and above behavior or disposition to behavior to the mind. However, behaviorism came under heavy attack especially for its neglect of internal states, and through the sustained criticism of people like Noam Chomsky the appellation became almost a term of abuse! However, recently there has been a resurgence of interest in behaviorism, and interested parties like Cotterill, while avoiding its excesses like the rejection of internal states and indeed deeming them as necessary constituents, have availed themselves of its idea of constructing mental activities in terms of bodily behavior and motor movement.

It is in this vein that Cotterill describes the brain as ‘a stimulus-response device’ and states that what constitutes the unifying characteristic of all animal responses including humans’ – with their varying degrees of sophistication, of course – is that ‘our goals are all accomplished by muscles.’ (p. 21) He claims that, except in those cases where the movement is part of a reflex, processes taking place in the brain determine the muscular output: mechanisms that produce an appropriate response for a given sensory input. He thus views the challenge of accounting for the mind, unlike the classical behaviorists, in terms of obtaining a clear picture of those intervening events. This naturally leads Cotterill to an extended treatment of brain functioning, but he argues that there is a certain continuity as things progress from simple devices to more complex ones like human brain. Steadily increasing demands on the performance of our brain does not require any radical change in what could be called the physics of its behavior, nor should it suggest that the processes underlying brain function involve principles not previously encountered in the scientific enterprise.

Against the backdrop of an evolutionary outlook on the brain’s function in terms of its sole contribution to the body’s survival and reproduction, Cotterill suggests that the evolution of the brain from its simplest configuration to the apex of its complexity in human beings has been only for the furthering of those goals. The cerebral cortex, as much as the limbic system, is nothing other than an embellishment that simply serves the same general cause, and the acquisition of a widened inventory of operational choices is only a means to enhance the organism’s chance of survival. In this light, it should not come as a surprise when thinking – the “pinnacle” of mental manifestation – is characterized by Cotterill as ‘a bodily function.’ (p. 59; original emphasis) More specifically, ‘thought proceeds through the simulation of muscular movements.’ (p. 338; original emphasis)

Cotterill uses the same strategy to extend his neo-behavioristic explanatory paradigm to other cerebral phenomena. He argues that the role of memory, for example, in the functioning of the real brain is to render it robust against externally imposed variations in its operating conditions, which, he claims, is achieved through muscular movements. He then goes on to marshal certain empirical evidence to show that memory is conditional on muscular activity. Similarly, ‘the little acorn’ of consciousness is subjected to the mechanistic modeling. However, before presenting Cotterill’s account, two preparatory points are in order.

First, although Cotterill admits that there is no unanimous and uncontentious definition of consciousness, he proposes, à la John Searle, a consciousness agenda that homes in on six structural characteristics of consciousness. These are the features that a successful theory of consciousness must meet: namely, subjectivity and qualia, unity and continuity of consciousness, intentionality, central and peripheral consciousness, familiarity, and boundary conditions or situatedness of consciousness. However, in this already “overgrown” review, only the first two characteristics are going to be considered.

Second, one should recognize that an essential evolutionary element in the emergence of consciousness is time. That is: ‘If the organism is to have the ability of responding to the temporal texture of its environment, on the time scale inherent in that texture, it will have to be able to retain a temporary record that spans a sufficient amount of that texture. And it will need cognitive mechanisms which exert relevant information from the texture, in the time available. Only then will a response be possible which exploits the choice implicit in the existence of that texture. Failing this, the information in that texture will be lost, and the resulting synaptic changes (if any) will merely reflect the statistics of the texture.’ (p. 333)

Now, subjectivity and qualia refer to how we as subjects of experience undergo experiential episodes with their qualitative/phenomenal features. Whereas the unity of and the continuity of the stream of consciousness refer ‘to the fact that our experiences occupy a single conscious field, irrespective of whether we are sensing external events or are occupied by our thoughts’, and our ‘experiences and thoughts are retained for a few seconds’ thus enabling ‘us to build upon them.’ (p. 320)

With the ‘time’ factor in mind and ensuring that environmental changes are not wasted on us, Cotterill claims that qualia arose ‘naturally from the need to monitor the significance for the body of the environment’s response to a volition-provoked stimulus.’ (p. 357) Subjectivity and its related qualia are thus seen in terms of the interplay between internal and external reafference of nerve signals. Cotterill also cites clinical cases such as ‘the observations on victims of multiple personality disorder’ as further justification for the idea that qualia are inextricably related to the body’s musculature. (p. 370) In the same spirit, he explains the unity and continuity of consciousness thus: ‘The unity of conscious experience stems from the fact that the premotor area acts as a bottleneck, policing planned movements so as to prevent them from bringing the body’s muscles into mutual conflict; the unity therefore stems from the fact that a muscle can adopt only one state at any given time, and this forces the system to follow only a single muscular path, which essentially determines the direction taken by the stream of consciousness.’ (p. 374)

There are, however, several ways of engaging critically with Cotterill’s conception of consciousness. At one level, one may attempt to assess his empirical descriptions and interpretations of the workings of brain’s neuronal machinery. But, as the technicalities are not within my competence, I shall refrain from venturing into such frays. At another level, one may take issue with some specific topics such as his account of concept formation, his predilection for a connectionist model of brain, his intimation of modularity of brain, or his evolutionary assumptions about cognition. Notwithstanding the theoretical tensions between modularity and connectionism concerning, for example, the issue of innateness and Cotterill’s own recognition of the limitations of the principle of association underlying neural networks (pp. 167ff.), I am going to look very briefly at the first and fourth topics.

Concepts are considered to be the most fundamental constructs in theories of mind, and naturally Cotterill attempts to shed some light on this all-important mental machinery. Given their importance to all aspects of cognition, it is also no surprise that concepts raise so many controversies and questions in philosophy and cognitive science.

Uncharacteristically, however, Cotterill’s treatment of concept formation is insufficiently detailed and is limited to such general statements as: ‘Our sensory systems generalize without us being aware of the fact. They effortlessly interpret the particular in terms of the general, thereby converting a percept to a concept.’ (pp. 162-3) Concept formation, Cotterill hints, is a matter of detecting ‘the underlying logic in’ input patterns and ‘making abstractions.’ (p. 174) But, this is very much reminiscent of the classical abstractionist theory of John Locke which has been found highly problematic and guilty of, inter alia, what Jerry Fodor has termed the inductivist fallacy. That is, theories purporting to explain new cognitive acquisitions like concepts can offer explanation on pain of presupposing the availability of the very concepts involved in the new acquisitions. The underlying thought here is that a stronger representational system cannot arise from a weaker one by means of general learning. Overall, Cotterill’s account of concept formation fails to grapple with any of the important issues surrounding the nature, structure and acquisition of concepts.

The other contentious aspect of Cotterill’s work is his evolutionary assumptions about cognition. His theory is built on the applicability of evolutionary criteria to cognition where it is assumed that natural selection is a sufficiently fine-grained process to be able to have an impact on cognitive capacities. Despite the appeal of explaining cognition as the result of evolution through natural selection, there are serious qualms about administering evolutionary explanations to cognitive capabilities. Natural selection is often deemed to be too coarse-grained to be sensitive to such traits, and evolutionary explanations of cognition seem be founded at best on an analogy with biological evolution. Notwithstanding the consideration that analogies are often poor means of persuasion, as genetics/evolution experts like Richard Lewontin, amongst others, have been persistently arguing, even if it were true that selection operated directly on cognition, we have no way of measuring the actual reproductive advantages. It is very important to recognize that the nature of any advantage accrued has to be couched in reproductive terms.

Also, any evolutionary reconstruction of that advantage must show that individuals or family groups, rather than the species as a whole, had such an advantage, since natural selection operates within populations to increase the frequency of some types and decrease others through differences in reproductive rates of individuals. Unless a more cognitively competent individual or its immediate family leaves more offspring than other families, selection will not increase the frequency of the selected character. Moreover, there is no necessary relation between the selective increase of a character in a species and any benefit to the species as a whole. There is no general principle of natural selection that operates to benefit a species as a whole. Generally, the problem is that there may have been no direct natural selection for cognitive ability at all. Cognition may have developed as the purely epiphenomenal consequence of the major increase in brain size, which, in turn, may have been selected for quite other reasons.

Yet, at another level, Cotterill is also facing challenges, of principle and not of detail, from his fellow naturalists, in particular, eliminative and anti-constructive naturalists. Like Cotterill, eliminativists maintain that the story of ‘the brain’s anatomy and physiology’ will tell the tale of mental life, but unlike Cotterill they claim that consciousness is not going to be a character in that narrative. It is simultaneously too simplistic, too vague, and too historically embedded in false and confused theory to designate a genuine phenomenon or set of phenomena in need of explanation. Cotterill’s silence on the eliminativism is rather conspicuous.

The other rival naturalist camp that Cotterill ignores is anti-constructivism. Basically, the position holds that although mind is a natural phenomenon, it is, in Colin McGinn’s terms, cognitively closed to us. There cannot be a naturalistic construction of consciousness because of our very cognitive constitution. Interestingly, Cotterill himself mentions the issue of cognitive closure and readily agrees with McGinn that ‘certain things are beyond us‘ but somehow fails to see that the case of consciousness itself could indeed be one of those very ‘holes in the mind.’ (p. 402; original emphasis).

Categories: Philosophical