From the 19th century to the 21st, the meaning of life changed, and with it the field of biology changed, too. It can be said that biology got going as a subject when it distinguished life, not from death, but from inorganic processes. Around 1910, Frenchman Stephane Leduc tried to close the conceptual gap between the living and the non-living with demonstrations of lifelike chemical forms. By selecting his colloids and solutions carefully and adjusting concentrations at appropriate stages, he created rather nice "osmotic productions", which look much like fungus. Like real life, these forms grew and sort of reproduced. Some people got excited; others did not know whether to laugh or cry.
Today, Leduc's ideas seem naive, and indeed they never provided an explanation about life that people could work with. The story of life had to wait for genes, and that undermined Leduc's gene-free approach, along with several others.
The creation of life, or perhaps rather the creation of lifelike forms, has ever since received a mixed reception. Today, it is trendy not to rely on chemical osmosis so much as computation. "Artificial life" has set itself the goal of studying how life emerges from appropriate organising principles, regardless of the medium it lives in. It does not have to be carbon-based, but if it is in a computer, so be it.
Making Sense of Life is Evelyn Fox Keller's meditation on these issues. Some biologists would rather observe than build, and those who build have to use their words carefully. Artificial life does not really need nutrition or metabolism in the same way real life does. Words such as nutrition and competition are metaphors, and can inspire scientists to see more than is there, or perhaps less. Why do species compete rather than collaborate? And when those metaphors are laden with the burdens of culture and stereotypes about what scientists do, there is scope for even more debate. Mother Nature hides secrets from us, especially in embryology, and the quest to explore takes on masculine and elitist overtones.
The book is divided into three parts, corresponding to historical periods. First, we have making sense of life without genes, which opens with Leduc and fizzles out with the untimely birth, as Fox Keller puts it, of mathematical biology. In the second part, the story develops with genes plus cybernetics. The third part splits in two. It starts with a review of the impact of microscopy and visualisation on biology - as it were, emphasising that seeing is believing. This celebration of technology is then followed by a discussion of computational models, ultimately artificial life, where computers are the technology rather than the various sorts of microscope.
Unfortunately, the parts of the book are disconnected: there is no real narrative building, apart from the implicit historical sequence, and there is no relation to the theme, rarely even to the title of the book. So, for instance, when we are asked whether "simulated organisms of cyberspace" meet the criteria of being alive, this question, though explicitly posed and apparently worrying philosophers and the rest of us, is dismissed as not germane to the concerns of the book. As narratives go, it lacks a point of view, other than that no simple point of view is possible.
Biologists are of necessity more closely wrapped up with their subject than the rest of us. What to a physical scientist might be a mathematical explanation can, we are told, become downright insulting if it seems to over-simplify life. Questions are "troubling". Making Sense of Life spends more time worrying about how we make sense of each other's science and use of metaphors than of the meaning of life itself. It worries about so-called lexical gaps, uses rhetorical questions and worries about words, in one case discussing the significance of introducing a new term for the modifier of a noun. Or is "model" a noun or a verb, and is its object unparseable but composite? I know what the words mean, but they make no sense to me here.
In a concluding chapter, Fox Keller admits that the central concern of the book is with the multiplicity of styles in scientific explanation. Indeed, the narratives in the three parts have their own different styles. The first is close to popular science, the middle rather uncertain and pedantic, and the last third a largely routine review of the impact of certain technologies in biology. In contrast to the popular start, only specialists will survive the middle. And the final third of the book has no clear audience: it is neither popular nor specialist. The popular reader will not be edified; the developmental biologist will know it already; and the philosopher will be frustrated with a shallow survey with no new insights making sense of life.
Ultimately, Making Sense of Life will be of interest to people who work in multidisciplinary fields, where hard and soft ideas confront each other and where people play with words. Those interested in making sense of life beyond these concerns will need to look elsewhere.
Harold Thimbleby is director, Interaction Centre, University College London.
Making Sense of Life: Explaining Biological Development with Models, Metaphors, and Machines
Author - Evelyn Fox Keller
ISBN - 0 674 00746 8
Publisher - Harvard University Press
Price - £19.95
Pages - 388