Philosophical Darwinism

On the Origin of Knowledge by Means of Natural Selection

Peter Munz

• Publisher: Routledge
• Year: 2002
• eBook ISBN:
  9781134884834
• Topic: Philosophy
• Subtopic: Philosophy History & Theory

Philosophers have not taken the evolution of human beings seriously enough. If they did, argues Peter Munz, many long standing philosophical problems would be resolved. One of philosophical concequences of biology is that all the knowledge produced in evolution is a priori , i.e., established hypothetically by chance mutation and selective retention, not by observation and intelligent induction. For organisms as embodied theories, selection is natural and for theories as disembodied organisms, it is artificial. Following Popper, the growth of knowledge is seen to be continuous from the amoeba to Einstein'. Philosophical Darwinism throws a whole new light on many contemporary debates. It has damaging implications for cognitive science and artificial intelligence, and questions attempts from within biology to reduce mental events to neural processes. More importantly, it provides a rational postmodern alternative to what the author argues are the unreasonable postmodern fashions of Kuhn, Lyotard and Rorty.

1
MAN’S GLASSY ESSENCE

proud man
Dressed in a little brief authority
Most ignorant of what he’s most assured—
His glassy essence

(Shakespeare, Measure for Measure, II,ii, 117–20)

I

For a long time almost all philosophers have held that if knowledge is a relation between a knower and something that is known, the two sides of this relation are formed by mind and matter. Mental events are events which ‘know’ the rest of the world, and the main reason for the presence of mental events is the fact that they do the knowing. The world somehow presents itself to the mind and the mind, somehow, represents what has been presented to it. Knowledge of other mental events or minds is a special case. In this model, other minds are either held to be like the knower’s mind, in which case knowledge of other minds is a form of self-knowledge, or they are taken to be as different from the knower’s mind as non-mental events, in which case the relationship of knowledge is exactly like a relationship between mind and matter. This model has a forceful prima facie plausibility. For we do know that there are mental events; and we do know that knowledge is a relation. The origin and persistent plausibility of the model comes from the presumption that these two incontestable facts must be linked together, and this presumption comes from the fact that we constantly talk about our mental events as if we knew what they contained or what they intended or what they were about. This kind of talk creates the illusion that at least some of their ‘content’ is unalterably known information about non-mental events. If one analyses how we talk about mental events and how our ability to do so comes about, we will see that this presumption is not justified. There are countless variations on this model. But it is no exaggeration to say that from Plato right down to the middle of the twentieth century some such model was used to deal with the phenomenon of knowledge. The model is deeply ingrained. When Richard Rorty in the late seventies became very famous for attacking it, he could not get himself to criticise the model on its own terms and show that, though knowledge is a relation, it is not a relation between mental and non-mental events. If there were knowledge, he accepted, it would be a relation between mental and non-mental events. He tried to show instead that there are no mental events and that, therefore, there can be no knowledge; and then he continued, ambiguously, that when we have knowledge, it merely duplicates what there is and is, therefore, superfluous. First he denied that there is mirroring and then he maintained that there is no point in mirroring. Against Rorty, I will maintain that knowledge is a form of mirroring and, therefore, a relationship and that, though consciousness (or mental events) takes place, it is not one of the terms of this relationship.

We have to revise the model in a different way. It was argued in the Introduction that we know from evolution, first, that there are mental events; and second, that knowledge is a relationship between knower and known and that the emergence of knowledge is anything but a mere duplication of what there is already. In criticising the traditional model we must, therefore, not jeopardise the notion of relationship, and we must take cognisance of mental events. The reason for criticising the model in which knowledge is a relation between mental and non-mental events is a simple one. We know from our studies of pre-human organisms that there is an enormous amount of knowledge in the world and that that knowledge is both acquired and stored without the intervention of mind. Hence, we must conclude that the function of mind, if it is at all crucial, cannot be the precondition of knowledge and that mind cannot be regarded as one term of the relationship. Mental events, when viewed in the light which modern neuroscience can throw on them, are not the sort of events which gather and store correct information about the world. Consciousness is not the sort of condition into which information can flow and by which it can be retained. What, then, are mental events, and how do they function and what role do they play in our knowledge of the world?

Unfortunately the old question ‘What is mind?’ was off to a bad start. It was off to a bad start when Descartes and Locke in the seventeenth century tried their hand at describing mental events. They gave as examples of mental events such activities as thinking, hoping, believing, doubting, wishing, etc. Attempts to describe mental events and subsequent attempts to relate them to or explain them in terms of bodily events have unfortunately remained bogged down in this initial selection of characteristics. Nobody would question that ‘doubting’, ‘believing’, or ‘thinking’ are mental events. But a closer look will show that these words refer to the way we are doing or holding something, that is, to their modality; not to the fact that the event itself is ‘mental’. They are rather descriptive of the modes of mental events. A real mental event is the feeling of sadness or feeling oneself to be a bat or, better, feeling what it is like to be a bat. Thinking about it, believing it to be true, wishing it to be true, doubting it, etc. is not itself a mental event at all, but merely a mode of the mental event. A mental event can be pin-pointed as being ‘thoughtful’ or as being ‘hopeful’, and so forth. It can be held to be in the thinking mode or the believing mode, etc. These modes are therefore the adverbial conditions of mental events, not a quality of mental events as such. When ‘mental’ was taken to refer to nothing more than the mode of doing something, it was easy as well as necessary for Ryle, for eliminative materialists and for identity theoreticians to argue convincingly that to speak of mental events is nothing but a different way of speaking of behavioural events. To label some events ‘mental’ was righdy and readily considered superfluous—a mere duplication. When we are doubting that the earth is flat, we are not doing two things—doubting (mentally) and behaving by saying ‘the earth is flat’. We are really doing only one thing in a doubting way. In modern times it has become fashionable to speak of prepositional attitudes rather than of beliefs. But such jargon does not help. It is true that the expression ‘attitude’ highlights the adverbial quality involved in the stance. But it is unwarranted to identify a mental event with a proposition. A proposition, as I shall argue later, is at best a labelled mental event, not a raw mental event. The distinction between the adverbial mode of behaviour and a genuine mental event is important. If it is not made, it is all too easy to think that since believing, willing, hoping, intending, etc. are merely modes of behaviour or dispositions, there are no mental events at all.

When philosophers mistook the adverbial mode for the ‘mental’ quality of an event, they predestined their reasoning about mental events to reach the conclusion that mental events reflect or mirror nature and that the cognitive relationship is a relationship between mind and matter. With such reasoning, one always ends up with the conclusion that ‘hoping for fine weather’ must be a mental event (‘hoping’) and that that event must refer to something non-mental—‘ fine weather’.

There is a corresponding bog which lies at the opposite end of the scale. This is the assumption that mental events occur when there is talk of universals, of meanings, of intentions or of any abstraction whatever. This tradition goes back to Plato but has found a large number of supporters in modern times who believe that mental events are algorithms or patterns or sets of rules for the computation of experiences or the representation of experiences. At present such computer rhetoric is more persuasive than the old-fashioned rhetoric about abstract universals. But on reflection, algorithms are no more mental than universals or the nervous system’s power to categorise and recognise similarities in the form of universals, and I would insist that to speak of ‘computational consciousness’ is a misuse of the word ‘consciousness’. The algorithms of a computer are not conscious, and if the human nervous system uses similar or comparable algorithms, there is no reason why we should describe them as ‘mental’ or ‘conscious’. If we do, the words ‘mental’ and ‘conscious’ are a pleonasm and do not add anything to the information we get when we refer to these operations as ‘algorithms’. Here again one must insist on the distinction between mental events and universals or algorithms. If one does not, one can easily lose sight of mental events, for it is possible to look upon algorithms as dispositions of the nervous system and then conclude that, if mental events are nothing but the algorithms in human or pre-human organisms, human organisms have no mental events because algorithms are not mental.

Hume thought about the matter in terms of a relationship between impressions and ideas, that is, between non-mental and mental events. Mental events (ideas) have their semantic properties by virtue of what they resemble: the idea of John is about John because it looks like him.¹ Brentano’s famous characterisation of ‘mental’ as intentional was an improvement; but only an improvement on Hume’s terms. Brentano’s intentionality helped us to gain a clearer notion of the difference between mental (ideas) events and non-mental (impressions) events, but this very clarity rammed Hume’s distinction even further in. Let us see how it has re-emerged in Searle. He begins his book on the matter with the statement that intentionality is the property of mental states.² The difference between a non-mental event and a mental event, he seems to be saying, is that the first refers to nothing and the second refers to something. The second represents something. This view is very Brentanoesque, and in so far as it goes a little beyond Hume, it must be wrong. There is a lot of intentionality in the sense of purposiveness in animals,³ even though it is not verbally articulated and in lower animals such purposive intentionality is not even unworded consciousness: it takes place without any, even pre-linguistic, mental event.

There are many theories about the relation between mind and matter or between mental and physical events. There is the dualism of Eccles and Popper, there is epiphenomenalism, there is the identity theory, there is eliminative materialism and there are several monistic theories. Philosophers bandy their position about with disguised dogmatism. Somebody says: ‘I am a monist, and therefore I regard neuronal activity to be both necessary and sufficient to account for mental events.’ Somebody else asserts: ‘I am a dualist, and therefore I regard neuronal events to be necessary but not sufficient to explain mental events.’ Seeing that we are so ignorant as to what constitutes a mental event and equally ignorant as to what constitutes a material event, we can only define the one in relation to the other. But this is like the blind leading the blind, and the contestants must invariably adopt a dogmatic attitude. One could emerge from such dogmatism only if one could define both mental events and material events separately and independently and then study the relation in which they stand to one another. But one cannot do it the other way round, i.e. start with the relation and then assert, dogmatically, that mental events are this and that, and material events, that and this.

By contrast, there are hardly any theories as to the actual emergence or generation of consciousness in human organisms. There are, however, good reasons for that absence. Consciousness by itself is not an adaptive phenomenon. As we have seen in the Introduction, it is only adaptive and has only been selected for because of its by-products. By itself it seems superfluous, and had it not been for its ability to force the generation of language, it would not have been an advantage at all and would, almost certainly, have disappeared soon after it had been thrown up as a mutation. By itself, it has only a negative advantage. It encourages inhibition and, as we shall see later, it helps us to imagine events which have not taken place and even events which cannot take place. In spite of the initial damage it inflicts, especially in regard to our social behaviour and given the ability to imagine what is not and to create visions alternative to reality, consciousness has proved a great social advantage. But all this is, if not properly negative, in the nature of damage control and only obliquely adaptive. For these reasons, the conventional strategy of explaining a feature by finding the reasons for which it is adaptive cannot be successful. At best, such explanations in terms of its adaptiveness have to pursue a very roundabout path. Since consciousness is not itself an adaptive feature, it is especially difficult to understand it. ‘No one really knows’, writes Johnson-Laird in his Mental Models,⁴ ‘what consciousness is, what it does, or what function it serves.’ It is not surprising that some of the most famous philosophical efforts of the second half of the twentieth century have been attempts to exorcise consciousness. In the early fifties, Gilbert Ryle called it the ghost in the machine and tried to show that there can be no such ghost because all talk about human behaviour which uses that ghost contravenes logic or semantics or syntax or all three. Correct use of language, he averred, does not allow a ghost to pull strings. The argument was very popular, though I cannot see for the life of me why Ryle’s linguistic norms should have been considered correct or why any linguistic norms, correct or false, should be able to pronounce on matters of fact such as whether there are mental events.

More recently the ghost has been seen as a homunculus. Daniel Dennett is famous for an attempt to show how we can do without the homunculus. He exorcises it by pointing out that when we pursue analysis of neuronal computations far enough down, we will not encounter a computing homunculus but only a myriad of very stupid (=mechanical) gadgets functioning one way or another. Talk of a directing homunculus, he is saying, is only short-hand for a vast number of computing processes. The actual events are non-intentional and so stupid that none of them deserves the name ‘homunculus’.

II

Let us avoid consideration of dogmatic theories about the relation between mental and physical events and start, instead, by comparing three recent and comprehensive treatments of consciousness: R.W.Sperry’s theory of the emergence of consciousness;⁵ Daniel Dennett’s theory;⁶ and G.M. Edelman’s theory of consciousness.⁷ The theories of Sperry and Dennett are separated by less than a decade, but they present two different theories widely separated by intellectual fashion. Neither Sperry nor Dennett has much concrete evidence to offer, and what makes them remarkably different is, first of all, the rhetoric they employ; and second, the models they use. Sperry wrote just before computer-jargon spread through philosophy, and Dennett is riding high on the crest of the computer-jargon wave. One will gain a good impression of the significance of the rhetoric involved if one notes that where Sperry uses the word ‘gnostic’, Dennett uses ‘cognitive’. ‘Gnostic’ places Sperry into the old tradition that goes back to post-biblical times, and ‘cognitive’ settles Dennett right in the middle of the computer revolution. Sperry observes that ‘most behavioural scientists today, brain researchers in particular, have little use for consciousness’, and Dennett, nine years later, that ‘if one looks in the obvious places…one finds not so much a lack of interest as a deliberate and adroit avoidance of the issue [of consciousness]’.

Sperry called his theory ‘emergent interactionism’. In this theory the emergence of consciousness is seen as a holistic event which flows through the entire nervous system. Conscious awareness is interpreted to be a dynamic emergent property of cerebral excitation. The more molar conscious properties are seen to supersede the more elemental physio-chemical forces, just as the properties of the molecule supersede nuclear forces in chemical interactions. Conscious awareness emerges through the hierarchical complexity of the nervous system, and when it does emerge, it affects the entire system so that it makes no sense to think of it as a relation between some parts of the nervous system and other parts. The emergent dynamic properties of certain of these higher specialised cerebral processes are interpreted as consciousness. The cerebral circuits which produce conscious effects may be understandable not in terms of isolated circuit principles, but in terms of advances in cerebral design superimposed on the background of an elaborately evolved central nervous system. Sperry must be aware of the rhetorical element in this description. The rhetoric glosses over the gaps in our understanding, but at the same time conveys a specific message. It states that consciousness emerges at a certain point of complexity and is a condition of the entire nervous system.

Edelman’s theory, like Sperry’s, is ‘holistic’, because it concludes that ‘the phenomenon of consciousness is the result of a particular order of animate matter that arose relatively recently in evolution’.⁸ But it is more detailed and more specific than Sperry’s. ‘Although consciousness is a process, we shall emphasise’, he writes with explicit reference to Sperry, ‘that it depends upon the particular organization of certain parts of the brain and not upon the whole brain.’⁹ Edelman’s theory—the details of which need not concern us here—is able to explain the difference between primary and higher-order consciousness and, therefore, able to show why some animals can be freed ‘from the dominance of an immediate driven response’,¹⁰ and can conclude that ‘through behaviour and particularly through learning, the continual interaction of this kind of memory with present perception results in consciousness’.¹¹

Edelman’s theory is more ambitious than Sperry’s, for it aims to show how we end up with consciousness which has a cognitive content. The basis for this theory is Edelman’s attempt to describe the precise nature of the interaction between the world and those neural events which result in consciousness. He argues that the motor activity of the neonate selects groups of neuronal maps for survival inside the body. These maps eventually start to interact, and the evolution of a self is made possible by this selective strengthening of connections within neuronal groups in accordance with the individual’s experiences. Edelman repeatedly stresses that the world thus ‘experienced’ is polymorphous and unlabelled.¹² But if it is, how can it select neuronal groups and lead to the formation of maps? He himself seems equivocal. He says that

the unlabelled world…is disjunctively sampled by various parallel sensorimotor channels [and that this] sampling results in the selection of combinations of neuronal groups…that are mapped in various ways. Selections of groups within different maps are correlated by reentry. For perceptual activity, at least one local map in a reentrant set must receive signals from a given sensory receptor sheet in a fashion which maintains some conformal relation to the spatiotemporal distributions of the realworld things and events that give rise to those signals.¹³

This process of global mapping ‘creates a spatiotemporally continuous representation of objects or events’.¹⁴ If the world is polymorphous and unlabelled, it is very difficult to explain how by neural group selection any veridical correspondence between the specific resulting consciousness and the world can be brought about, or, for that matter, how we can give any meaning to the notion of correspondence. The neural system is able to categorise correctly; and it derives this ability from the fact that it has been selected to do so. But in order to establish the mechanism of selection, Edelman slips in again and again the proposition that signals are caused by the spatio-temporal configurations objects and events have in the real world of things over and above what we perceive them to have.

Dennett starts at the opposite end. He gives us a description, following Thomas Nagel, of consciousness as the ability to know what it feels like to be something and then, starting from the top, so to speak, goes down the scale to analyse what kind of functional organisation our neuron...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• PREFACE
• ACKNOWLEDGEMENTS
• INTRODUCTION: COGNITIVE CONDITIONS
• 1: MAN’S GLASSY ESSENCE
• 2: THE DUBIOUS CREDENTIALS OF POSITIVISM
• 3: THE LURE OF SOCIOLOGY
• 4: THE NATURE OF THE MIRROR
• 5: THE VIEW FROM SOMEWHERE
• NOTES