Ideas: A History from Fire to Freud

But if most educated people accept now that psychoanalysis has failed, it also has to be said that the concept of consciousness, which is the word biologists and neurologists have coined to describe our contemporary sense of self, has not fared much better. If, by way of conclusion, we ‘fast-forward’ from the end of the nineteenth century to the end of the twentieth, we encounter the ‘Decade of the Brain’, which was adopted by the US Congress in 1990. During the ten-year period that followed, many books on consciousness were published, ‘consciousness studies’ proliferated as an academic discipline, and there were three international symposia on consciousness. The result? It depends who you talk to. John Maddox, a former editor of Nature which, with Science, is the foremost scientific journal in the world, wrote that ‘No amount of introspection can enable a person to discover just which set of neurons in which part of his or her head is executing some thought-process. Such information seems to be hidden from the human user.’ Colin McGinn, a British philosopher at Rutgers University, New Jersey, argues that consciousness is resistant to explanation, in principle and for all time.¹⁹ Other philosophers, such as Harvard’s Thomas Nagel and Hilary Putnam, argue that at present (and maybe for all time) science cannot account for ‘qualia’, the first-person phenomenal experience that we understand as consciousness, why, in Simon Blackburn’s words, the grey matter of the brain can provide us with the experience of, for example, yellow-ness. Benjamin Libet, in a series of controversial experiments, has claimed that it takes about half a second for consciousness itself to happen (‘Libet’s delay’). Whether this (if true) is an advance is not yet clear. John Gray, professor of European thought at the London School of Economics, is one of those who has identified such phenomena as the ‘hard problem’ in consciousness studies.²⁰

On the other hand, John Searle, Mills Professor of philosophy at the University of California, Berkeley, says there is nothing much to explain, that consciousness is an ‘emergent property’ that automatically arises when you put ‘a bag of neurons’ together. He explains, or tries to, by analogy: the behaviour of H₂O molecules ‘explains’ liquidity, but the individual molecules are not liquid – this is another emergent property.²¹ (Such arguments are reminiscent of the ‘pragmatic’ philosophy of William James and Charles Peirce, discussed in Chapter 34, where the sense of self emerges from behaviour, not the other way round.) Roger Penrose, a physicist from London University, believes that a new kind of dualism is needed, that in effect a whole new set of physical laws may apply inside the brain, which account for consciousness. Penrose’s particular contribution is to argue that quantum physics operates inside tiny structures, known as tubules, within the nerve cells of the brain to produce – in some as yet unspecified way – the phenomena we recognise as consciousness.²² Penrose actually thinks that we live in three worlds – the physical, the mental and the mathematical: ‘The physical world grounds the mental world, which in turn grounds the mathematical world and the mathematical world is the ground of the physical world and so on around the circle.’²³ Many people, who find this tantalising, nonetheless don’t feel Penrose has proved anything. His speculation is enticing and original, but it is still speculation.