The Wallace Problem
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The Wallace Problem Part I Animal Cognition For those who believe our general cognitive abilities are on a qualitatively different scale to that of say a bonobo or a chimp, the advent of this difference represents a significant enigma known as the Wallace Problem – after Alfred Russell Wallace, Darwin’s collaborator on the Theory of Evolution. He differed from Darwin in believing, as most people still do, that humans have qualitatively superior intellectual capacities and cognitive powers to any other species. Why is this a problem? Well, with both Darwin and Wallace, we believe all our capacities have been arrived at by evolution and that evolution produces traits that are selected by giving enhanced reproductive survival chances. Species that are both predator and prey, who live in social groups, and for whom survival both within the group and of the group is evolutionary relevant, should, the theory suggests, be equipped by evolution with similarly relevant suites of cognitive skills. Most importantly, species that are both close in descent and face such similar life situations and problems should arrive at similar traits. Thus when it comes to closely related species facing similar life problems, evolution tends to produce a fairly continuously varying set of results, rather than a very disparate set. Indeed even when quite distantly related species end up facing similar problems, evolution tends to come up with similar solutions – in such cases we call it convergent evolution; for example this is why air breathing mammalian dolphins and whales have ended up looking very like water breathing, non- mammalian, fish. But, despite facing similar problems and having pretty much identical brain structures to our nearest primate relatives, it was claimed by Wallace, and by countless others since, that the cognitive skills of the species Homo Sapiens are totally different from all others, even those of our close primate relatives. This does appear to be fairly self-evident when we compare the rich inner mental life we perceive humans to have to that of our animal brethren. The Wallace problem is thus:- Why is there such a difference? How could evolution have produced a massive cognition difference between such closely related species? We shall examine here the reasons for believing that, instead of what Wallace believed, the cognition of species forms pretty much a continuum, and that our nearest neighbours’ cognition is qualitatively similar to, rather than qualitatively different from, our own. If this is the case then the Wallace problem is one that is unlikely to exist in the broad form in which it has been traditionally conceived. I shall argue that it reduces down to a much more specific evolutionary question which I’ll attempt to address in Part II. Does Clever Behaviour Imply Clever Learning? We can break down what appear to be clever responses to situations as being accomplished by three broad methods – a) hard-wired information and responses, by which I basically mean clever but instinctual behaviour; 1 b) simple acquiring of information – e.g. clever behaviour produced by learning associations between behaviour and beneficial result through trial and error, or by copying observed behaviour; c) cognition – actually thinking something out by reflecting on the information available, pondering the problem until, via some degree of comprehension, one comes up with a solution. The success (or indeed failure) of this solution is then itself new information which will be used in the future – as can be seen in the fact that related problems subsequently encountered are much more quickly solved. The assumption behind the Wallace Problem is that the third of these methods, cognition, requires a fully consciousness being to accomplish, and that full consciousness is confined to humans. So it is in the issue of cognition that the Wallace Problem arises, and to this we will address ourselves. The Desire for Human Uniqueness in Cognition It seems that most of modern humanity has long has a need to view itself as unique in its cognitive abilities. This need has produced a whole set of perceived differences that we have, at one time or another, elevated to the level of an important principle by which we can be isolated from the rest of the animal world. Let me refer to these as Human Uniqueness Indicators, HUIs for short. Looking back on the last 100 years or so we can see a pattern emerging:- A particular HUI is first decided upon by postulate or casual observation. It then grows in acceptance until reaching a state of accepted fact by philosophers, psychologists and scientists. It is challenged by findings of apparent presence in other species, but such challenges are initially simply dismissed out of hand. However the challengers defend and support their position with new findings. The new findings then grow in number until the HUI defenders are fighting what looks increasingly like a rear-guard action. Eventually, if the evidence of the possession of this ‘HUI’ by other species becomes too voluminous to dismiss, the defenders withdraw its HUI status, often with some of its supporters finding that, in retrospect, they never really saw it as an important HUI at all! Alternatively the HUI may be narrowed with additional constraints, not yet shown in other species, and the whole cycle repeats. The ‘only humans can do’ status of cognitive HUIs is usually first breached with apes (chimps, bonobos, gorillas) – our nearest relatives and most like us, and therefore the species to whom the Wallace problem most applies. It is often only then that there are serious attempts to see if more distant species can also accomplish something along these lines. Our understanding then spreads like an outgoing wave – to dolphins, elephants, dogs, crows, & so on. Despite this recurring pattern, the adherents of the Wallace Problem have remained in the majority in the philosophical and (though to a much lesser extent now) the scientific world for most of the 20th Century. The stubbornness of the postulate of human cognitive uniqueness has been supported by a number of people simply dismissing reports of animal cognition. The tendency of many pet owners, and people involved in caring for animals, to attribute mental and emotional states to their subjects has been dismissed as naive anthropomorphism. Philosophers in particular have been scathingly dismissive of any attempt to give the ‘inner world’ of any other species, no matter how closely related, most of the mental features we take for granted in ourselves. However they have been much less forthcoming as to how & why evolution might have created this huge difference. Human Uniqueness Indicators (HUIs) 2 Let me group the received wisdom of unique human cognition, or equivalently animal inabilities, into eight broad categories:- 1 Animals learning is not via true cognition but is only achieved in a simplistic response-reward manner. Human learning, by contrast, requires introspection and reflection until sufficient aspects of a problem are understood to enable solutions to be created. 2 Humans create and employ tools for anticipated future use. Where animals appear to do so it is simple manipulation of what is immediately to hand when faced with an immediate goal that is otherwise not achievable. Such uses may be seen as trial and error behaviour simply re-enforced by reward. 3 Animals have no self-awareness – the proof is taken to be that they do not recognise themselves when in front of a mirror 4 Animals have no “Theory of Mind”, an over-pretentious term philosophers use to mean that animals can’t see something from another animal’s perspective, and in turn are incapable of empathy, and hence have no sense of fairness – all these associated qualities are unique to humans. 5 Animals live only in the present – they can neither reflect upon the past nor contemplate the future. Hence what are highly advantageous evolutionary behaviours of humans, such as avoiding past mistakes, planning for the future, and deferring of gratification in order to obtain greater future rewards, are not possible for animals. 6 Animals groups cannot develop distinct cultural behaviours or politics (societal manipulation strategies) as all human groups do. 7 Humans are capable of meta-cognition by which is meant thinking about ones thinking, in particular evaluating the reliability of one’s knowledge and modifying one’s actions according to such reliability evaluation – no animals are capable of this. 8 If you forgive me I’ll leave naming the eighth until after we have dealt with the first seven. The evidence for these HUI claims has not come from some uncanny ability to see inside the minds of other animals, but rather from the absence of any evidence in their external behaviour of their possessing these abilities. Thus absence of evidence is taken as evidence of absence. As we have discussed before in other topics, the validity of this conclusion is crucially dependent upon whether or not there are any barriers that might exclude is from seeing the presence of evidence; if these barriers are low or non-existent then it is reasonable to draw conclusions from its absence, however if the barriers to obtaining the evidence are high then their absence may have no significance and the conclusion that it’s absence constitutes evidence is unjustified. There is no doubt that our inability to simply ask animals what they think represents a significant barrier to obtaining any evidence on the quality of their thought – thus we have to work a little harder to investigate the problem. We can certainly agree that humans possess all of the above seven named qualities, but let’s see if detailed observation and experimentation supports the view that they really are absent in all other species:- 3 1 Animal Learning We are gradually realising that discovering what learning strategies are being used by another species requires significant knowledge of the needs, problems and lifestyle of that species.