Philosophical Foundations of Neuroscience. P. M. S. Hacker
Чтение книги онлайн.
Читать онлайн книгу Philosophical Foundations of Neuroscience - P. M. S. Hacker страница 20
![Philosophical Foundations of Neuroscience - P. M. S. Hacker Philosophical Foundations of Neuroscience - P. M. S. Hacker](/cover_pre1026049.jpg)
Misascription of psychological attributes to parts of the cortex andto neurons
The twentieth century saw the growth of the misascription of psychological powers to parts of the cortex and to neurons rather than to the experiencing, behaving human possessing the cortex with its neurons. The experimental attempt over the past two thousand years to understand the functions of the brain have matured along the only path that is logically possible, namely: seeking correlations of the kind described above. However, the realization of this has been increasingly lost over the history of neuroscience to the present day. This is manifest in researchers asserting that the particular cortical area or neuron under study is the experiencing agent, forgetting that it is the correlations of that area/neuron with human experience and behaviour that identified the region under consideration in the first place. It might be argued that Blakemore, Zeki, Damasio, Tononi and many others are simply ascribing psychological predicates to different cortical areas and their neurons as a convenient shorthand, but an appraisal of their work shows that not to be the case. Clearly this is untenable.
2 Philosophical Problems in Neuroscience: Their Conceptual Roots
The history of neuroscience shows that our understanding of cortical function is founded of necessity on correlations with human behaviour and experience. We now consider a different approach, based on logico-grammatical grounds, to the question of whether psychological attributes (seeing, thinking, remembering, etc.) can be attributed to a part of the cortex, either an anatomical part or a group of neurons.
Psychological attributes are attributes of the sentient creature as a whole
This approach was initiated by Aristotle in the fourth century bc. Aristotle states in his De Anima that ‘To say that the psuche¯ is angry is as if one were to say that the psuche¯ weaves or builds. For it is surely better not to say that the psuche¯ pities, learns, or thinks, but that the man does these things with his psuche¯.’ Here Aristotle is emphasizing that pitying, learning and thinking can be sensibly attributed only to human beings, not to some principle of life that informs their body, namely the psuche¯ (sometimes incorrectly translated as ‘soul’). In the nineteenth century Lewes restated Aristotle’ s conception in its modern form. In his The Physical Basis of Mind (1891) he states that ‘It is the man and not the brain, that thinks; it is the organism as a whole and not one organ that feels and acts.’ In the twentieth century Wittgenstein offers the same thought in his Philosophical Investigations (1953), ‘Only of a living human being and what resembles (behaves like) a living human being can one say: it has sensations, it sees; is blind; hears; is deaf; is conscious or unconscious.’
Aristotle, Lewes and Wittgenstein are pointing out that there are no logico-linguistic grounds for attributing psychological predicates to the brain, parts of the brain, or indeed any other parts of the body, rather than to behaving human beings. The logic of part/whole relations is known as mereology. The misattribution of psychological predicates by many neuroscientists we call the mereological fallacy in neuroscience. The conceptual confusions arising from this fallacy, together with the fact that the history of cognitive neuroscience is a search for correlations with behaviour, makes clear that it is humans that experience, not their brains or parts of their brains.
Notes
1 1 M. R. Bennett, S. Hatton, D. F. Hermens and J. Lagopoulos, ‘Behavior, neuropsychology and f MRI’, Progress in Neurobiology, 145–146 ( 2016), pp. 3–6.
2 2 Ibid., p. 17.
1 The Growth of Neuroscientific Knowledge: The Integrative Action of the Nervous System
The conceptual framework for early investigations into the biological basis for human sensory, volitional and intellectual capacities was set by Aristotle’ s philosophical writings on the psuchē and pneuma. The early growth of neuroscientific knowledge was dominated by the question of how the contraction of muscles involved in voluntary movements of limbs is effected. However, Aristotle’ s own rudimentary investigations, which led him to believe that the blood vessels initiate muscle contraction, were a false start. It was, above all, Galen’ s much later discoveries of the nerve supply to muscles from the spinal cord that made it clear that it is the nerves that carry out this function. Galen’ s work initiated 2,000 years of enquiry into how the spinal cord and brain are involved in voluntary movement and into the reflex origins of some movements. The identification of motor and sensory spinal nerves, the role of the spinal cord in reflex movements, and the relationship between the action of the brain and the spinal cord in voluntary and reflex movement were all resolved by experiments. These involved observations on muscles and limbs following lesions to different parts of the nervous system. In this way a conception evolved of how the functions of the brain, spinal cord and nerves are integrated to give the final motor output.
The conceptual framework within which neuroscientific knowledge grew originated in Aristotelian thought, but it was subsequently transformed by the Cartesian revolution in the seventeenth century. In this chapter we shall adumbrate the development of ideas concerning the neural basis of animate functions, concentrating increasingly upon what Sherrington, among the greatest of neuroscientists, called ‘the integrative action of the nervous system’, as it applies to movement. This sketch of the history of the slow growth of knowledge about the nervous system and its operations will display some of the conceptual difficulties encountered by natural philosophers over the centuries as they grappled with the problems concerning the biological foundations of characteristic powers of animate beings in general, and humans in particular. As we shall see, the roots of current conceptual difficulties in cognitive neuroscience are buried deep in the past. Grasping this aspect of our intellectual and scientific heritage will help to bring current conceptual problems into sharp focus. These problems are the principal concern of this book.
It might be asked why we do not concentrate more on the role of the great sensory systems, such as vision, in our historical sketch of the integrative action of the nervous system. The reason is that the early neuroscientists took up the challenge of understanding the motor system first, for it allowed experimentation which they could undertake to test their ideas with the techniques then available. This was not the case with the sensory systems. These pioneers saw the need to integrate their account of the sensory systems into their evolving knowledge of muscular contraction and movement. This led them to speculate on the relationship between vision and motor performance. It did not, however, add much to our understanding of how vision occurs, a subject that had to wait for techniques that became available only in the nineteenth and especially the twentieth century.1
1.1 Aristotle, Galen and Nemesius:The Origins of the Ventricular Doctrine
Aristotle’ s conception of the psuchē
Aristotle (385–322