Behind the Eye stems from Donald MacCrimmon MacKay’s course of 1986 Gifford Lectures given at the University of Glasgow. The volume, published posthumously in 1991, was edited by MacKay’s widow with assistance from Professor Neil Spurway of the University of Glasgow. In both the lectures and the subsequent volume, MacKay’s concern for bringing theology into dialogue with contemporary trends in information theory and neurophysiology forms the crux of his argument.
In chapter 1, ‘Under Our Own Microscope’, MacKay introduces the difficulties found in coming to a cogent understanding of identity within the context of the neurosciences. Though some philosophers and neuroscientists would advocate an objective methodology for understanding the brain, the mind, cognition or identity, MacKay advocates a subjective approach (what he calls the ‘I-Story’), which emphasises the embodied nature of the conscious mind. His discussion of the mechanics of consciousness is buttressed in chapter 2, ‘Within the Living Brain’, by a detailed discussion of the anatomy and physiology of the human brain. Specific reference is given to the technologies that enable recording and monitoring of real-time brain events.
Moving from physiology to pragmatics, in chapter 3, ‘What are Brains for?’, MacKay reflects on how the brain’s activity relates to one’s subjective consciousness of the world. Though he alludes to the brain as an information system and references to the ‘circuits of the brain’, he remains consistent in his preference for the ‘I-Story’ as the means of understanding consciousness. This contrasts with appeals to a reductionist or materialist preference for the computational analogy of the brain, or even the so-called ‘Brain-Story’. He observes: ‘Materialism … has reality standing on its head, for what we know first and foremost are the facts of the I-Story. Our conscious experience is the platform upon which even our doubting must be based …’ (p. 59). He does not describe this as a dualism (that is, a duality of ‘mind’ and brain) but as a ‘comprehensive realism’ that holds in tension the subjective I-Story and the objective ‘Brain-Story’ as two equally valid modes of describing an isomorphic reality.
In chapter 4, ‘Perception’, and chapter 5, ‘Seeing Is not Believing’, MacKay discusses the nature and limitations of human perception. He begins by distinguishing between two kinds of perception: perception as experience and perception as behaviour. The former he describes as an analogue of the psychological study of perception; the latter is a facet of the study and development of automata. In order to understand perception, one must take into account both the function of classification and its resulting action. He notes that although perceptions are reliable, they are not without their vagaries. The pursuit of truth, as a function of perception, must always be understood as an ambiguous endeavour.
Chapter 6, ‘Reading the Mind’, moves the focus from an examination of perception and stimuli to an analysis of the inner workings of the brain itself. In this chapter, MacKay again discusses many of the different kinds of brain-scanning technologies and comments on what these various instruments reveal about complex brain states. This is followed by chapter 7, ‘The Divided Brain’, where he explores what impact, if any, the physiology of a divided brain has upon perception, intersubjective dialogue and personality.
In chapter 8, ‘Brains and Machines’, MacKay addresses the shortcomings of mechanical analogies of the brain and consciousness. Though mechanistic images have been used throughout his work to describe the ‘circuits’ of neurons and the information flow of the brain as a system, with this chapter he dismisses the ability to reduce the human brain to a strict mechanical analogy. Further comment is also provided on the inadequacies of Artificial Intelligence research, where the tendency to reduce the brain to a machine is critiqued. MacKay argues that the brain is simply too complex for any satisfactory machine analogy. Keeping with the theme of complexity, in chapter 9, ‘My Fault or My Brain’s?’, MacKay discusses the issue of free will, indeterminacy and decision making in connection with complex brain states. Moving beyond issues solely relevant to brain science, MacKay also touches on the possibility of Divine foreknowledge. In chapter 10, ‘Where Do Ideas Come From?’, MacKay continues his discussion on the nature of cognition, pointing out how the random processes of the brain contribute to the emergence of personal thought. He observes that the implications for an emergent theory for personhood might also challenge the idea of a personal deity, noting in particular the idea of a ‘god in dialogue’. In chapter 11, ‘Knowing More than We Can Tell’, MacKay follows the work of Michael Polanyi, and focuses his attention on what is termed ‘tacit knowledge’, that is, knowledge which is felt but cannot be verbalised.
MacKay concludes his course of lectures in chapter 12, ‘And in the End?’, by examining the eschatological implications of his materialist understanding of identity. If, as he has argued throughout this course of lectures, one’s ‘I-Story’ is directly tied to one’s embodiment, he inquires into the destiny of the self after death. His solution to the problem of persisting identity seeks to embed the whole self (physiology and psychology) in the being of God, who is described as both author and creator of the cosmos.