IN 1959, C. P. Snow warned about the widening gulf between the sciences and
humanities. As this gulf enlarges, it becomes more urgent to explore and express
scientific ideas in ways that make explicit their relevance to and impact on
human psychological and social needs. The thought-provoking approach in The
Cambridge Quintet, John Casti’s “scientific fiction” about the beginnings
of artificial intelligence theory, is one of which Snow himself might well have
approved.

The fictional story occurs in the oppressive and contrived setting of a
Cambridge dinner party held by Snow for four “great minds”—Alan Turing,
Ludwig Wittgenstein, J. B. S. Haldane and Erwin Schrödinger—to
investigate the feasibility of duplicating human thought in a machine.

Each course served by Snow’s manservant, Simmons, heralds a new round of
virtuoso but ultimately sterile and esoteric discourse, with Turing and
Wittgenstein at loggerheads and the others on the fence, all showing remarkable
insensitivity for one another’s feelings and backgrounds. The upshot is a lack
of real communication and movement which nonetheless, aided by Casti’s
hindsight, presages many issues in AI theory, including the distinction between
processing and understanding information and the influence of language and
social interaction on thought.

Besides presenting ideas in a novel and scholarly way, I was unsure what
Casti wanted to achieve in The Cambridge Quintet. He concludes,
cautiously, that capturing human cognition within a machine is very problematic,
and that humans and machines have distinct forms of intelligence that will take
them in different directions.

As an exposition of scientific exchange, I suspect the book will be as
off-putting to the majority as it may be inspiring to a few. As historical or
social analysis, it appears prejudiced by the kind of discretist logic and
hindsight used all too readily to identify exceptional hero-figures rather than
social context as the causal agents of intellectual development. Moreover, I
think the use of real historical personalities who may not have chosen the words
put in their mouths undermines the unconstrained exploration of ideas which
offers the most promising role for scientific fiction.

From this perspective, the first questions to ask when trying to explain the origins of biological diversity should not be about what organisms need to do to be competitive or what their ancestors were like. Instead, it is important to understand what kinds of structural and/or behavioural patterns living systems are capable of giving rise to as a consequence of the way they are organised. The historical and adaptational explanations provided by Neo- Darwinism, in which individual genetic units are envisaged to struggle for existence under relentless selection pressure, are thereby seen to concern important but secondary issues. They tell why features persist and become refined, but yield no insights into how or even why they came into being.

These are important and controversial ideas which I find very alluring. If they are to gain ground, it is important to explore their full implications and describe them in a relevant context at the same time as attracting attention and avoiding alienation.

As the title of the book demonstrates, Goodwin is certainly good at attracting attention. The “leopard” is in fact Goodwin’s way of depicting the Neo-Darwinian view of organisms. It has distinctive “spots”, which arise from three fundamental misconceptions. Goodwin deals with these misconceptions uncompromisingly, relating how the spots disappear when scrutinised in the right light. The notion that genes provide the complete set of instructions for assembling an organism is, he states, incorrect. DNA is not an independent replicator because it needs a cellular context in which to operate. In many unicellular or indefinitely growing organisms there is no clear distinction between soma (the body of an organism) and germ plasm (that part of the organism which is incorporated into future generations).

Drawing credibility from his extensive historical and mathematical awareness, Goodwin then sets about describing the phenomenon of “emergence” – the manifestation or appearance of novel, ordered patterns of organisation or behaviour as the product of interactions between system components. This “order out of chaos” phenomenon can, he says, even account even for such classical conundrums as the evolution of the vertebrate eye. In the last part of the book he develops a strongly partisan approach to social and environmental issues.

Such powerful advocacy is unlikely to go unnoticed. However, it always carries the risk of alienating potential converts who might be put off by what they perceive to be extremism, or who may just get upset by the dismissive tone Goodwin sometimes adopts, for example, when he describes reductionism as “bad science”.

I also wonder whether Goodwin has found the best context for exploring his ideas in the fullest and most relevant way. He draws extensively on icons that are all too familiar icons of chaos and complexity theory, such as the Beloussov-Zhabotinsky reaction, the aggregating slime mould and the fibrillating heart as well as his own pet organism, the green alga Acetabularia. He never seems explicitly to recognise the importance of indeterminacy (open-endedness) or the related problems of defining discrete organisational units in living systems. He therefore doesn’t quite detach himself from discretist thinking.

Goodwin also uses language and concepts that depend on a strong background knowledge of chaos and complexity theory, while taking pains to tell us that Ca²⁺ is the chemical symbol for a calcium ion and that slime moulds are endearingly named. This may not help him to communicate with, for example, the mainstream of biologists who know little about nonlinearity.

However, taken as a whole, warts (or should I say spots?) and all, this is an intellectually challenging book that is written with considerable verve and courage. Goodwin clearly hopes that it will contribute to a more elegant and inspiring vision of life processes that sees organisms – including ourselves – as subjects to be treated with respect, rather than as objects to be pushed and pulled around by external forces and competitive struggle. I hope so too.