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Foreword to the Second Edition

Denis Noble CBE FRS hon FRCP

The publication of the second edition of this book nearly two decades after its first publication is a suitable occasion to review what it achieves and why that is important.

It has certainly succeeded in bringing a high degree of rigour to the interaction between science and philosophy in the field of neuroscience. Many of the questions raised by scientific discovery are conceptual and cannot be answered by further empirical discovery alone. Nor can conceptual analysis be dissociated completely from empirical discovery. As just one example, the deep questions about the nature of our universe raised by the discoveries of quantum mechanics and relativity would not have seemed relevant if nineteenth-century certainties about a purely deterministic universe working in a purely Cartesian space had been confirmed. That is one of the reasons why collaboration between active scientists and active philosophers is necessary.

It is also one of the reasons the authors refer in their introduction to ‘the fact that the potentiality for conceptual confusion is buried deep in our language. Such confusions can be eliminated for a few decades by painstaking conceptual analysis. But they will rise again, as younger generations fall into the same traps. Sense data died under critical onslaught in the 1950s and 1960s, but by the end of the century internal representations arose phoenixlike from their ashes.’

It seems to me to be obvious that language needs constant re-analysis as the meanings of words change, new metaphors arise and new potential confusions occur. Yet, by and large, twentieth-century science was not ready to accept that philosophy had anything of any importance to contribute. That view was based on the idea that science and philosophy as they were understood in the seventeenth century had confused the two, even to the extent of naming the first scientific journal Philosophical Transactions of the Royal Society. Originally published in 1665, its first editor, Henry Oldenburg, was as much at home discussing (in long correspondences in Latin) with the philosopher Benedict Spinoza as he was with the scientist Isaac Newton. One of Spinoza’s great philosophical works was nearly published in the journal.

In later centuries the idea grew that, once issues that had initially been raised as philosophical issues had become the subject of practical empirical enquiry, there was no longer any need for further philosophical analysis. That depended of course on the conviction that the initial conceptual distinctions had been set in stone and were no longer open to question.

I see the signs that the twenty-first century is proving to be more aware of the pitfalls this creates. To take just one example that has been the subject of my own research recently, the discoveries that led to the so-called central dogma of molecular biology, formulated by Crick in 1958 after the earlier empirical discovery of the double helix, were presented in the last century as an unquestioned empirical fact. Yet the reason they were viewed in that way was itself based on a deep misunderstanding of the nature of the DNA molecules. Following in the footsteps of the quantum-mechanics pioneer Erwin Schrödinger, the genetic material was assumed to reproduce itself like a crystal. You will find that assumption hidden away in the textbooks, and sometimes openly acknowledged in the popularizations, such as Richard Dawkins’s The Selfish Gene, where he explicitly says, of DNA replication, that ‘This is how crystals are formed.’

We now know that DNA does not function like a crystal in living cells, nor does it reproduce itself accurately. In fact, the copying process is so inaccurate that there would be hundreds of thousands of copy errors if the cell did not come in to ensure faithful transmission to the next generation by systematically proof-correcting the inaccurate copies.

With that fact alone, many other foundations in evolutionary biology turn out to be conceptual errors. I have detailed those errors elsewhere.¹ They are fundamental to our view of ourselves as humans and our place in the universe, and raise many philosophical questions that had been considered closed, such as whether we and other organisms are purposeful.

Neuroscience, like any other field of science, cannot be immune from such problems raised by assumptions that creep into our views of the world and then become treated as accepted facts. The problems raised by metaphysical assumptions masquerading as empirical facts are just one example where collaboration between science and philosophy is necessary.

Finally, I wish to draw attention to the fact that this edition is not simply the original book updated. As the authors explain in their introduction, the book has been substantially rearranged to separate out conceptual problems that individually require more extensive treatment. Moreover, a vast literature, particularly on new technical methods, is out there to be taken into account.

I particularly appreciate the fact that there is now a separate chapter (3) concerned with the conceptual problems arising from ascribing to the brain properties that can only sensibly be ascribed to the organism as a whole. I see this point as a natural ally to my own arguments for multilevel interpretations of organisms (the principle of biological relativity), since those arguments lead to demonstrations that it does not make sense to ascribe functions, purposes and goals to levels of organization that could not possibly integrate those functions. As an example from my own field of physiology, it does not make sense to ascribe to the molecules of the heart the function of pumping blood around the body. Functions and purposes can only be ascribed to levels where they make sense (in this case to the complete circulatory system), and some of those (psychological attributes) are necessarily applied sensibly only to the whole living being. As the authors emphasize throughout their book, if a property cannot sensibly be ascribed to something, then it is not an empirical question whether it is or is not the case. Both answers would be meaningless.

Separating chapter 3 from its related conceptual problems, such as introspection, enables those problems to be more thoroughly analysed in chapter 4. While reading that chapter I tried to imagine what it would be like for me to be in the privileged position of being an observer in some future neuroscience laboratory. My privilege would be to observe, through some yet-to-be-invented high-resolution process (vastly higher resolution than current scanning methods), the detailed molecular and electrical neural and other body processes that had been discovered to be those associated with me thinking about, for example, the square root of minus 1. And I realized of course that, were that to be possible, I would be just like those neuroscientists. I would have no idea how to interpret all the electrical and molecular events as somehow ‘being’ my idea of the square root of minus 1. I would be just as ignorant as I would be if gazing at the series of 0s and 1s in a computer readout of its binary-number activity when calculating a problem involving complex numbers.

That inability in understanding my own brain processes would have nothing to do with the problem I already had as a student when first grappling with and learning the concept of imaginary numbers (I use this example only because it readily shows just how absurd it would be to claim that one could ‘see’ imaginary numbers in my brain!). For I would also be none the wiser if the question I had been imagining while my brain was being examined was a much less problematic one, perhaps what I wished to eat for breakfast. The only way for those processes to be understood, by me or by the neuroscientists, would be for it to be me thinking those thoughts and telling the world what I was thinking. But the neuroscientists could learn that directly from me without recording from my brain.

I think this is a general problem in the multilevel understanding of organisms, not limited to the brain and nervous system. As I have already indicated in this foreword, all science requires conceptual analysis as an ongoing process.

Notes

1 1 D. Noble, ‘The illusions of the modern synthesis’, Biosemiotics (2021), https://doi.org/10.1007/s12304-021-09405-3.

Denis Noble CBE FRS hon FRCP

31 May 2021