Wednesday, 6 July 2011

The Presence of the Past – Rupert Sheldrake ***

Reviewing a Rupert Sheldrake book is a little like sitting on the jury in the trial of an infamous murderer (sorry, Rupert). As such a juror it is very difficult to ignore all that you have read in the press and to take an impartial line. Similarly, although this is the first time I have read one of Sheldrake’s books, I approach it in a cloud of awareness that this may be flaky science.
Nothing typifies this better than the rather weasely reaction from that usually superb publication New Scientist. The book’s publisher has put a quote on the cover from NS in a review of the original 1988 edition of this book (this is the 2011 second edition). The quote reads ‘Engaging, provocative… a tour de force.’ Yet NS felt compelled to write ‘It’s usually a pleasure to see [our] reviews being mined for promotional pull-quotes. But not always. Sometimes it feels like desperate barrel-scraping on behalf of the publisher.’ In fact there is no barrel-scraping going on here – it’s a straightforward pull quote which, as always picks out the good bit of the review. Yet New Scientist is backpedalling at high speed, trying to make it look like a misrepresentation.
So I will do my best to come at this without blinkers, but I can’t guarantee not to be influenced. First reactions were not great. In part this is just because it’s a very long book at 484 pages, and in part because it is a popular science book about a person’s own theory. In my experience this hardly ever works, especially if it is a theory that challenges conventional scientific thought, as it tends to come across as a demented rant. This feeling isn’t helped by the opening where in his second sentence Sheldrake uses one of the key identifiers of crank science writing: he refers to ‘The so-called laws of nature…’ That expression ‘so-called’ always raises the baloney antennae.
As I continued to read I was also rather irritated by two other things. One is the amount of tedious repetition. In the first sixty pages or so he makes a single point that could have been made in a paragraph. No wonder it’s so long. The other is a repeated (much repeated) assertion that we have moved from a picture of an unchanging clockwork universe to an evolving universe. This totally misunderstands the nature of a ‘clockwork’ universe. Just because a universe is deterministic (or obeys probability driven rules) does not make it unchanging. Clockwork inherently moves and changes, otherwise it wouldn’t be much of a clock.
There is always a huge danger of drawing loose parallels with a different branch of science, and to describe the changes that have occurred in the physical universe as evolution, something Sheldrake repeatedly does, is simply wrong. Evolution (in the scientific sense) does not mean changing alone, but developing in a way that is driven by reproduction incorporating random mutations and subject to conditions where some variations survive and some don’t. Physics and cosmology do not work this way. They don’t evolve.
Still, we can cope with the loose generalizations if the theory itself stands up. Sheldrake’s central assertion is that through a process he calls morphic resonance, nature builds up habits, making it easier and easier to do the same thing over time. This means that things that have been around a long time (like atoms) will appear to always work the same way (approximating to natural laws), but things that haven’t been around long will not have settled into habitual paths and so will be more random. He applies this to everything. Not just atoms, for example, but particularly species of bird, chemical compounds or pieces of music (for instance).
Here is the first real problem with this theory. Sheldrake gives the example ‘… when animals such as rats are trained to learn a new trick in one laboratory, other rats of the same breed everywhere else should subsequently tend to learn the same trick more quickly.’ It seems this morphic resonance only works in the same breed. But how does it know to do so? Breeds are a fairly arbitrary human concept. Each rat is different in terms of its DNA – each is a mutant (just as we all are). So it can’t depend on having identical DNA. But how else can the morphic field know to work just on that one breed of rat? It doesn’t make any sense.
I frankly don’t know enough about biology to say for certain, but it seemed to me that Sheldrake’s description of genetics (and epigenetics) was very much a 1980s view. There is hardly any mention of the role of junk DNA, or of other known extra-genetic factors. When it came to physics it seemed his need to emphasise fields was too strong. Yes, fields are central to modern physics but we would describe the light from a distant galaxy reaching us in terms of photons, not a field extending between the two as Sheldrake seems to suggest.
A lot of my problems with the book are about feel rather than substance. Too much is based on ancient Greek philosophy, with endless debates on the benefits of a Platonic versus an Aristotelian view, which has very little to do with science. But there are some key scientific problems too. He tells us that crystal formation relies on morphic resonance, so a newly formed chemical is difficult to crystallise and doesn’t have a standard form. But over time, influenced by statistical combination of past crystals, the form becomes more and more standardised. If this were the case we would expect that after billions of years of ice crystals forming there would be a standard shape for a snowflake, not the vast array of six-pointed forms we see.
Talking about the ‘morphic resonance’ that he believes underlies the shaping of everything from animals to molecules, Sheldrake says ‘unlike [normal physical] resonance, morphic resonance does not involve a transfer of energy from one system to another, but rather a non-energetic transfer of information.’ Whoa! Thermodynamics malfunction alert! To have a non-energetic transfer of information would break the second law of thermodynamics, and to quote the great Arthur Eddington, If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations – then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation – well these experimentalists do bungle things sometimes. But if your theory is found to be against the second law of thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation.
In the end, I think those who dismiss Sheldrake as a charlatan or a crank get it wrong. This is a carefully argued idea that has every right to be heard. The author makes some interesting points, like the way geographically separated animals appear to learn behaviours without any means for those behaviours to be transmitted (though of course there is always the ‘time was right’ idea of simultaneous development).
As a world picture, Sheldrake’s vision suffers from being a biologist’s viewpoint, rather too easily led down hand-waving paths involving airy-fairy fields, and there seems little reason for thinking Sheldrake is right. But we do science a disservice if we take the New Scientistview and dismiss him out of hand. It is a turgid, over-long book, but it is an interesting idea that deserved to be heard.
Also on Kindle:  
Review by Brian Clegg

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