And it cannot explain how an animal perceives or thinks by reference to the brain’ s, or some part of the brain’ s, perceiving or thinking. For it makes no sense to ascribe such psychological attributes to anything less than the animal as a whole. It is the animal that perceives, not parts of its brain, and it is human beings who think and reason, not their brains. The brain and its activities make it possible for us – not for it – to perceive and think, to feel emotions, and to form and pursue projects.
While the initial response of many neuroscientists to the accusation of conceptual confusion is to claim that the ascription of psychological predicates to the brain is a mere façon de parler, their reaction to the demonstrable fact that their explanatory theories nontrivially ascribe psychological powers to the brain is sometimes to suggest that this error is unavoidable due to the deficiencies of language. We confront this misconception in chapter 14, where we show that the great discoveries of neuroscience do not require this misconceived form of explanation – that what has been discovered can readily be described and explained in our existing language. We demonstrate this by reference to the much discussed phenomena resultant upon commissurotomy, described (or, we suggest, misdescribed) by Sperry, Gazzaniga and others (§14.3 [§17.3]).
In Part II we investigate the use of concepts of perception, memory, mental imagery, emotion and volition in current neuroscientific theorizing. From case to case we show that conceptual unclarity – failure to give adequate attention to the relevant conceptual structures – has often been the source of theoretical error and the grounds for misguided inferences. It is an error, a conceptual error, to suppose that perception is a matter of apprehending an image in the mind (Crick, Damasio, Edelman), or the production of a hypothesis (Helmholtz, Gregory), or the generation of a 3-D model description (Marr). It is confused – a conceptual confusion – to formulate the binding problem as the problem of combining data of shape, colour and motion to form the image of the object perceived (Crick, Kandel, Wurtz). It is wrong, conceptually wrong, to suppose that memory is always of the past, or to think that memories can be stored in the brain in the form of the strength of synaptic connections ( Kandel, Squire, Bennett). And it is mistaken, conceptually mistaken, to suppose that the investigation of thirst, hunger and lust is an investigation into the emotions ( Rolls) or to think that the function of the emotions is to inform us of our visceral and musculoskeletal state ( Damasio).
The initial reaction to such critical remarks may well be indignation and incredulity. How can a flourishing science be fundamentally in error? How could there be unavoidable conceptual confusion in a well-established science? Surely, if there are problematic concepts, they can easily be replaced by others that are unproblematic and that serve the same explanatory purposes. Such responses betoken a poor understanding of the relation between form of representation and facts represented, and a misunderstanding of the nature of conceptual error. They also betray ignorance of the history of science in general, and of neuroscience in particular.
Science is no more immune to conceptual error and confusion than any other form of intellectual endeavour. The history of science is littered with the debris of theories that were not simply factually mistaken, but conceptually awry. Stahl’ s theory of combustion, for example, was conceptually flawed in ascribing, in certain circumstances, negative weight to phlogiston – an idea that made no sense within its framework of Newtonian physics. Einstein’ s famous criticisms of the theory of electromagnetic aether (the alleged medium by which light was thought to be propagated) were directed not only at the results of the Michelson–Morley experiment, which had failed to detect any effect of absolute motion, but also at a conceptual confusion concerning relative motion involved in the role ascribed to aether in the explanation of electromagnetic induction. Neuroscience has been no exception – as we show in our historical survey. It is true enough that the subject is now a flourishing science. But that does not render it immune to conceptual confusions and entanglements. Newtonian kinematics was a flourishing science, but that did not stop Newton from becoming entangled in conceptual confusions over the intelligibility of action at a distance, or from bafflement (not remedied until Hertz) over the nature of force. So too, Sherrington’ s towering achievement in explaining the integrative action of synapses in the spinal cord, and thereby eliminating, once and for all, the confused idea of a ‘spinal soul’, was perfectly compatible with conceptual confusions concerning the ‘cerebral soul’ or mind and its relation to the brain. Similarly, Penfield’ s extraordinary achievements in identifying functional localization in the cortex, as well as in developing brilliant neurosurgical techniques, were perfectly compatible with extensive confusions about the relation between the mind and the brain and about the ‘highest brain function’ (an idea borrowed from Hughlings Jackson).
In short, conceptual entanglement can coexist with flourishing science. This may appear puzzling. If the science can flourish despite such conceptual confusions, why should scientists care about them? Hidden reefs do not imply that the seas are not navigable, only that they are dangerous. The moot question is how running on these reefs is manifest. Conceptual confusions may be exhibited in different ways and at different points in the investigation. In some cases, the conceptual unclarity may affect neither the cogency of the questions nor the fruitfulness of the experiments, but only the understanding of the results of the experiments and their theoretical implications. So, for example, Newton embarked on the Optics in quest of insight into the character of colour. The research was a permanent contribution to science. But his conclusion that ‘colours are sensations in the sensorium’ demonstrates failure to achieve the kind of understanding he craved. For, whatever colours are, they are not ‘sensations in the sensorium’. So in so far as Newton cared about understanding the results of his research, then he had good reason for caring about the conceptual confusions under which he laboured – for they stood in the way of an adequate understanding.
In other cases, however, the conceptual confusion does not so happily bracket the empirical research. Misguided questions may well render research futile (examples will be examined in relation to mental imagery (§6.3.1 [§7.3.1]) and voluntary movement (§8.2 [§9.2])). Rather differently, misconstrual of concepts and conceptual structures will sometimes produce research that is by no means futile, but that fails to show what it was designed to show (examples will be discussed in relation to memory (§§5.2.1–5.2.2 [§§6.2.1–6.2.2]) and to emotions and appetites (§7.1 [§8.1])). In such cases, the science may not be flourishing quite as much as it appears to be. It requires conceptual investigation to locate the problems and to eliminate them.
Are these conceptual confusions unavoidable? Not at all. The whole point of writing this book is to show how to avoid them. But, of course, they cannot be avoided while leaving everything else intact. They can be avoided – but if they are, then certain kinds of questions will no longer be asked, since they will be recognized as resting on a misunderstanding. As Hertz put it in the wonderful introduction to his Principles of Mechanics: ‘When these painful contradictions are removed, … our minds, no longer vexed, will cease to ask illegitimate questions.’ Equally, certain kinds of inferences will no longer be drawn from a given body of empirical research, since it will be realized to have little or no bearing on the matter which it was meant to illuminate, even though it may bear on something else.
If there are problematic concepts, can they not be replaced by others that serve the same explanatory function? A scientist is always free to introduce new concepts if he finds existing ones inadequate or insufficiently refined. But our concern in this book is not with the use of new technical concepts. We are concerned with the misuse of old, nontechnical concepts – concepts of mind and body, thought and imagination, sensation and perception, knowledge and memory, voluntary movement, and consciousness and self-consciousness. There is nothing inadequate about these concepts relative to the purposes they serve. There is no reason for thinking that they need to be replaced in the contexts that are of concern to us. What are problematic are neuroscientists’ misconstruals of them and the misunderstandings consequently engendered.
