Monday, 30 July 2012

The Black Hole in “The Believing Brain”

Some comments of Michael Shermer's book “The Believing Brain

How you react to this book, which has just been issued as a paper back, will depend on your own individual belief systems. In setting out to read it I felt it appropriate to identify places where the book reinforced my own beliefs and – more importantly – where there is a conflict – and why. As a result what follows is a personal commentary rather than a formal review. In particular it ends with a discussion on theories of how the believing brain works. It also looks at some of the reason why your believing brain might not accept an unconventional evolutionary model which suggests that the human brain is little more than an enlarged animal brain which is only more powerful because it has more neurons, has more synapses, a modified developmental framework and similar straightforward homologous changes. 

Before I started reading there were two areas where I felt there would be common ground – we are both atheists, although Michael prefers to call himself a skeptic - and an important aspect of this blog is how we are trapped by our beliefs, and the common beliefs of the society we live in. However once I had read the book I came to the conclusion that his account left a “black hole” in the description about how the brain works which leaves room for a “God of the Gaps” which I am sure was not his intention. While I accept the exceptional differences in what humans can do when compared with animals I feel his statement that “our brains are the most complex and sophisticated information processing machines in the universe” suggest that his belief system parallels the Medievalists who claimed that the Earth is the centre of the universe because they didn't know any better. 

But before I get onto the critical issues it would only be fair to say that I found much of interest in the book

The section Journeys of Belief contains three well-chosen case studies. As someone who has personal knowledge of mental health problems in the family and in voluntary work for many years the chapter on Mr D'Arpino's Dilemma came as no surprise as I know the whole question of diagnosis of mental illness (and the question of what is normal) is difficult. I found Dr. Collin's conversion helpful in understanding why some friends became Christians, as living in England I have had little experience of American evangelists. I read A Skeptic's journey (Michael's own story) with interest, especially when he described the effects of extreme exhaustion, which made me aware of the importance of different life experiences and differences which might be due to minor generic differences between individuals. I enjoyed reading the chapters in Belief in Things Unseen about the afterlife, god, aliens beings, and conspiracies – undoubtedly because the views expressed tended to reinforced my existing beliefs. While further on I found the chapter Confirmations of Belief and Geographies of Belief made me think.

As far as I am concerned the difficult area is in the section The Biology of Belief. The chapter The Believing Neuron is a well written review of the current state of research while the chapter Paternicity brought to my attention aspects of pattern learning research which were new to me – and made be think hard about my own research. The chapter on Agenticity jumps to the point where humans observer patterns and often assign agents to explain them. The problem is that he never adequately describes the genetically controlled “agent” which ensures that the neurons store the learnt/cultural patterns and uses them to make decisions such as ascribing “agency” to the cultural patterns we have learnt.

Later in the book he says a lot about the Belief in the Afterlife and Belief in God, and provides a lot of evidence to suggest that both afterlife and gods are a figment of the imagination. However the explanations, however good there appear to be are descriptive at the level that “the clock strikes the hour when the long hand points at 12” without any explanation of the chain of activity between the bits of metal inside and the noise generated. But this is the very area where the religious will claim that there is something special and the soul resides!

In fact there seems to be a black hole in published scientific knowledge in this area (see The Black Hole in Brain Research) and not just as it is described in this book. Michael clearly has a good understanding of how science works, as exemplified by the Epilogue, with many examples through the book, including the chapter on Geographies of Belief, and his reference to psi is particularly relevant:

Why don't scientists accept psi? Daryl Bern has a stellar reputation as a rigorous experimentalist and he has presented us with statistically significant results. Aren't scientists supposed to be open to changing their minds when presented with new data and evidence? The reason for skepticism is that we need both replicable data and a viable theory, both of which are missing in psi research. [My emphasis]

Clearly there is always a difficulty in trying to get data which will prove the negative and while there is an enormous amount of data as been collected about various specialist aspects of the working brain there is a lack of a clear overall theory to provide an evolutionary plausable information pathway between the neuron and what the brain actually does at an intellectual level.

I would suggest that a reason for this theoretical gap is revealed in the chapter A Skeptic's journey (Michael's own story). I found his views on “hard” and “soft” science revealling. He wrote:

The physical sciences are hard, in the sense that calculating differential equations is difficult, for example. The number of variables within the causal net of the subject matter, however, is comparatively simple to constrain and test when contrasted with, say, computing the actions of organisms in an ecosystem or predicting the consequences of global climate change. Even the difficulty of constructing comprehensive models in the biological sci­ences, however, pales in comparison to that of the workings of human brains and societies. By these measures, the social sciences are the hard disciplines, because the subject matter is orders of magnitude more complex and multifaceted with many more degrees of freedom to control and predict.

But surely the biological mechanisms which links the neuron foundations to the observed way human process information at the highest level must describable in physical science terms in the same way that one can describe how a stored program computer handles information independently of which applications it is running. And we don't say that we cannot model how a computer works because of the vast number of different applications it can execute.

Rather than grumble that the subject matter of social science is “is orders of magnitude more complex and multifaceted with many more degrees of freedom to control and predict” it is more useful to consider that social science is just one of many information processing activities that the human brain can undertake. And of course in future our brain may evolve to handle even bigger problems. So let us assume that the number of different theoretically possible “items of information” that a human brain might process is infinite.

Now the physical sciences are used to handling very large numbers, and mathematical equations that go off to infinity. If the brain has (in theory) to be able to process an infinite number of “items of information” it probably has a simple “universal” processing routine which will process any “item of information”. As the “items of information” being processed by an individual human brain will vary from single nerve signals up to concepts such as “god” or the concept of evolution, the simple “physical science” approach would suggest that an “item of information” is composed of a network of other “items of information” in a recursive fashion – and recursion is known to be a very powerful mathematical tool.

A model based on the idea that “all information is the same” and is processed recursively is potentially attractive for the following reasons:
  1. The brain contains large numbers of identical neurons (all presumably doing similar things) linked into a network which must have a recursive manner of operation to handle the more complex ideas.
  2. Such a model should provide a clear-cut boundary between the biological mechanisms (which are disinterested in the meaning of the information) and learnt cultural knowledge.
  3. Animal brains also process information (but apparently on a more limited scale) but the model could be equally applicable to them. Bearing in mind the way changes happen in evolution, the biggest differences between an animal brain and a human brain could be due to scale and not novel mechanisms.
The big question is whether such a simple model can be constructed and and whether it will explain how the brain evolved and works. In the spirit of The Believing Brain I believe that the ideas discussed in the Brain Storms on this blog, such as An Evolutionary Model of the Brain's Internal Language lay the foundations for such a model, and the earlier research on CODIL shows that such a model is capable of significant information processing. 

However you have a believing brain andmay choose to reject my belief, and not explore my ideas further, possibly because you haven't read the chapter Confirmations of Belief and the many different kinds of bias that it lists. It could be that your believing brain accepts as an inalienable fact one (or more) of the following propositions:
  1. We are not just animals with big brains – We believe know that humans are more intelligent than animals because there must be some very special novel processes about their brain which cannot simply be explained in terms of bigger capacity, more synapses, developmental changes in the skull, and other normal evolutionary homologous processes.
  2. We believe know that science has advanced so far that all the simple ideas have been fully explored – and the future depended on more and more narrower and narrower specialisation to work out the finest details. The time when there was a need for any scientist to stand back and try and get a better view of the forest has gone when there are so many leaves left to be turned over. In any case you ideas do not fit comfortably with the leave I am currently researching so you must be wrong.
  3. We believe know that interesting new ideas can only come from large teams of scientists working in well funded institutions and there is no longer a place for the individual in science.
  4. Exceptional claims need exceptional proof. Exceptional new claims are ones which challenge position of the establishment which believes knows that it is correct and is in the comfortable position of controlling the exceptional resources the claimant will need in order to produce the exceptional proof. Therefore all exceptional new claims can happily be rejected as unproven and unsound.
I will end with a quote from the last page of the Epilogue of the book:

... by the very same process of forming beliefs about the universe and ourselves, we are also more capable than any other species of self-deception and illusion, of fooling ourselves even when we are trying to be fooled by nature.”

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