Monday, 30 January 2012

Sell-by date: are old science books still worth reading?

As an outsider to the world of science I've recently been struck by an apparent dichotomy that I don't think I've ever heard discussed, namely that if science is believed by non-practitioners to work on the basis of new theories replacing earlier ones, then are out-of-date popular science (as opposed to text) books a disservice, if not positive danger, to the field?

I recently read three science books written for a popular audience in succession, the contrast between them serving as the inspiration for this post. The most recently published was Susan Conner and Linda Kitchen's Science's Most Wanted: the top 10 book of outrageous innovators, deadly disasters, and shocking discoveries (2002). Yes, it sounds pretty tacky, but I hereby protest that I wanted to read it as much to find out about the authors and their intended audience as the subject material itself. Although only a decade old the book is already out of date, in a similar way that a list of top ten grossing films would be. In this case the book lists different aspects of the scientific method and those involved, looking at issues ranging from collaborative couples (e.g. the Curies) to prominent examples of scientific fraud such as the Chinese fake feathered dinosaur fossil Archaeoraptor.

To some extent the book is a very poor example of the popular science genre, since I found quite a few incorrect but easily verifiable facts. Even so, it proved to be an excellent illustration of how transmission of knowledge can suffer in a rapidly-changing, pop-cultural society. Whilst the obsession with novelty and the associated transience of ideas may appear to somewhat fit in with the principle that a more recent scientific theory always replaces an earlier one, this is too restrictive a definition of science. The discipline doesn't hold with novelty for the sake of it, nor does an old theory that is largely superseded by a later one prove worthless. A good example of the latter is the interrelationship between Newton's classical Law of Gravitation (first published in 1687) and Einstein's General Relativity (1916), with the former still used most of the time (calculating space probe trajectories, etc, etc).

The second of the three books discusses several different variants of scientific practice, although far different from New Zealand particle physicist Ernest Rutherford's crude summary that "physics is the only real science. The rest are just stamp collecting." Stephen Jay Gould's first collection of essays, Ever Since Darwin (1977), contains his usual potpourri of scientific theories, observations and historical research. These range from simple corrections of 'facts' – e.g. Darwin was not the original naturalist on HMS Beagle – to why scientific heresy can serve important purposes (consider the much-snubbed Alfred Wegener, who promoted a precursor to plate tectonics long before the evidence was in) through to a warning of how literary flair can promote poor or even pseudo-science to an unwary public (in this instance, Immanuel Velikovsky's now largely forgotten attempts to link Biblical events to interplanetary catastrophes).

Interestingly enough, the latter element surfaced later in Gould's own career, when his 1989 exposition of the Early Cambrian Burgess Shale fossils, Wonderful Life, was attacked by Richard Dawkins with the exclamation that he wished Gould could think as clearly as he could write! In this particular instance, the attack was part of a wider critique of Gould's theories of evolutionary mechanisms rather than material being superseded by new factual evidence. However, if I'm a typical member of the lay readership, the account of the weird and wonderful creatures largely outweighs the professional arguments. Wonderful Life is still a great read as descriptive natural history and I suppose serves as a reminder that however authoritative the writer, don't take accept everything on face value. But then that's a good lesson in all subjects!

But back to Ever Since Darwin. I was surprised by just how much of the factual material had dated in fields as disparate as palaeontology and planetary exploration over the past thirty-five years. As an example, Essay 24 promotes the idea that the geophysical composition of a planetary body is solely reliant on the body's size, a hypothesis since firmly negated by space probe data. In contrast, it is the historical material that still shines as relevant and in the generic sense 'true'. I've mentioned before (link) that Bill Bryson's bestseller A Short History of Nearly Everything promotes the idea that science is a corpus of up-to-date knowledge, not a theoretical framework and methodology of experimental procedures. But by so short-changing science, Bryson's attitude could promote the idea that all old material is essentially worthless. Again, the love of novelty, now so ingrained in Western societies, can cause public confusion in the multi-layered discipline known as science.

Of course, this doesn't mean that something once considered a classic still has great worth, any more than every single building over half a century old is worthy of a preservation order. But just possibly (depending on your level of post-modernism and/or pessimism) any science book that stands the test of time does so because it contains self-evident truths. The final book of the three is a perfect example of this: Charles Darwin's On the Origin of Species, in this case the first edition of 1859. The book shows that Darwin's genius lay in tying together apparently disparate precursors to formulate his theory; in other words, natural selection was already on the thought horizon (as proven by Alfred Russel Wallace's 1858 manuscript). In addition, the distance between publication and today gives us an interesting insight into the scientist as human being, with all the cultural and linguistic baggage we rarely notice in our contemporaries. In some ways Darwin was very much a man of his time, attempting to soften the non-moralistic side to his theory by subtly suggesting that new can equal better, i.e. a form of progressive evolution. For example, he describes extinct South American mega fauna as 'anomalous monsters' yet our overtly familiar modern horse only survived via Eurasian migration, dying out completely in its native Americas. We can readily assume that had the likes of Toxodon survived but not Equus, the horse would seem equally 'anomalous' today.

Next, Darwin had limited fossil evidence to support him, whilst Nineteenth Century physics negated natural selection by not allowing enough time for the theory to have effect. Of course, if the reader knows what has been discovered in the same field since, they can begin to get an idea of the author's thought processes and indeed world view, and just how comparatively little data he had to work with. For example, Darwin states about variations in the sterility of hybrids whilst we understand, for example that most mules are sterile because of chromosomal issues. Yet this didn’t prevent the majority of mid-Victorian biologists from accepting natural selection, an indication that science can be responsive to ideas with only circumstantial evidence; this is a very long way indeed from the notion of an assemblage of clear-cut facts laid out in logical succession.

I think it was the physicist and writer Alan Lightman who said: "Science is an ideal but the application of science is subject to the psychological complexities of the humans who practice it." Old science books may frequently be dated from a professional viewpoint but can still prove useful to the layman for at least the following reasons: understanding the personalities, mind-sets and modes of thought of earlier generations; observing how theories within a discipline have evolved as both external evidence and fashionable ideas change; and the realisation that science as a method of understanding the universe is utterly different from all other aspects of humanity. Of course, this is always supposing that the purple prose doesn’t obscure a multitude of scientific sins...