Getting the wiggle into the act

Colin McGinn

  • A History of the Mind by Nicholas Humphrey
    Chatto, 230 pp, £16.99, May 1992, ISBN 0 7011 3995 1

Consciousness is not sempiternal, it has a history, a natural genesis. Once upon a time the universe contained no consciousness; then it sprang up here and there; and now the planet is flooded with the stuff. This is not to make the trivial observation that what people think and feel changes over time and generations, sometimes quite radically; it is a point about the deep biological roots of consciousness. Just as animal bodies are products of a long evolutionary process, in which chance variation is rigorously winnowed by natural selection, so animal minds must have a remote genesis in the mechanisms of differential survival as they worked on the available materials. Eyes gradually emerged as engines for exploiting the information contained in light, relying on the given chemical and optical properties of matter; and consciousness likewise must have emerged for some good biological reason, building on the prior properties of organisms. The question is how and why this happened: how did mentality arise from cell tissue? Answering this question would tell us not merely about the aetiology of consciousness: it would also help us to understand the nature of consciousness – particularly its relation to its physical substrate. If we knew the history of mind, then we would have effectively solved the mind-body problem, since we would understand how consciousness arises from matter.

Nicholas Humphrey’s book is a bold and speculative attempt to reconstruct mental history and hence to develop a theory of consciousness. He has a good project, and he is bracingly undaunted by its difficulty. He has a number of interesting and sensible things to say about a variety of topics, from the affective dimensions of colour to the nature of blind-sight. And he writes in a fresh (if jaunty) style. But in the end, I fear, the theory he proposes is a dismal failure: it doesn’t work at all. Don’t blame the author, though; blame the problem – it is just so hard. Like most attempted theories of consciousness, Humphrey’s looks like a contender only by trading on a mixture of obscurity and circularity. What is instructive about it are the manifest contortions needed to offer something with even the appearance of a decent theory. You see Humphrey being driven from pillar to post, alternating confidence with aporia, in a doomed attempt to lasso his quarry. Consciousness still swims out of reach, flaunting its mysterious gleam.

The book starts encouragingly enough, by locating the problem in the nature of basic first-order sentience. Humphrey tells us, dis-armingly, that in his earlier work he ‘came in at too high a level and left the fundamental problems unsolved’. ‘Too high a level’ was the level of self-reflection – knowledge of one’s states of consciousness. This leaves quite untouched the prior question of the nature of the mental states themselves – the pains, the tickles, the seeings of red, the smellings of roses. How do these spring from mere irritations of nervous tissue? Humphrey now sees the problem, correctly, as that of ‘explaining how states of consciousness arise in human [sic] brains’: how do we get from brain cells to subjective sentient fields?

Humphrey’s theory has two main parts: 1. a distinction between sensation and perception, with consciousness attaching directly only to the former; and 2. the suggestion that to have a sensation is for the brain to initiate a feedback loop from its core to its periphery. Both parts of the theory strike me as fundamentally flawed and crucially unclear.

The full text of this book review is only available to subscribers of the London Review of Books.

You are not logged in