Skip to main content

The Hidden Half - Michael Blastland *****

Michael Blastland is co-author of one of my favourite titles on the use and misuse of numbers, The Tiger that Isn't - so I was excited to see this book and wasn't disappointed.

Blastland opens with the story of a parthenogenic crustacean that seems to demonstrate that, despite having near-identical nature and nurture, a collection of the animals vary hugely in size, length of life and practically every other measure. This is used to introduce us to the idea that our science deals effectively with the easy bit, the 'half' that is accessible, but that in many circumstances there is a hidden half that comprises a whole range of very small factors which collectively can have a huge impact, but which are pretty much impossible to predict or account for. (I put 'half' in inverted commas as it might be fairer to say 'part' - there's no suggestion that this is exactly 50:50.)

We go on to discover this hidden half turning up in all kinds of applications of science and maths from economics to healthcare, from the lives of individuals who were delinquent as children to measuring the benefit (or not) of giving a poor family a cow. Blastland picks out a number of factors that tend to mislead us - that as humans we aren't consistent in our responses, that things change with location and time, that the way research is undertaken can generate false results, that principles can mislead us and far more. As he points out, what this does is make us aware of the limitations of applied maths (particularly economics) and science. He is not saying we shouldn't use them - they are far better than the alternatives - but we have to be aware of their limitations.

At the end of the book, Blastland comes up with some suggestions for dealing with the hidden half. It isn't going to go away, and there are no easy solutions, but he does have some interesting ideas on mitigation. For example, he suggests we should experiment more (with political policies, for example), remember that we are betting on knowledge rather than making use of certainty and, for me, most importantly that scientists, journalists and politicians should do more to communicate the uncertainty involved. It's not that we want our politicians to be hesitant, but it would be far better if they made it clear that there are very few clear linkages between policies and outcomes. I was particularly struck by some data on GDP figures. The media and politicians often spend ages agonising over a GDP change of, say 0.2 per cent. The headline figures are revised over time as better data is available: Blastland points out that a typical correction might be 0.4 per cent up or down (and can be as high as 1 per cent). This makes it very clear that making pronouncements based on a 0.2 per cent change is futile and highly misleading.

My only criticism is that I felt that the book could have done with even more specific examples: in this kind of book, it's the examples that have the real bite and savour. Blastland spends a bit too long philosophising on the hidden half in a way that feels a little repetitive. It's not there aren't great examples (plenty more than the ones mentioned above), it was just for me that the ratio of examples to musings wasn't quite right. A brief mention also to the cover design - it's very clever (though I couldn't help thinking it had been put on wrong and wanting to re-position it).

We are getting more books now about the reality of applied maths (particularly economics) and science, which is an extremely good thing, provided the message is carried through to journalists and others who have to communicate these matters to the public. An excellent book.
Hardback:  

Kindle:  
Using these links earns us commission at no cost to you
Review by Brian Clegg
Labels:

Comments

Post a Comment

Popular posts from this blog

Why Nobody Understands Quantum Physics - Frank Verstraete and Céline Broeckaert **

It's with a heavy heart that I have to say that I could not get on with this book. The structure is all over the place, while the content veers from childish remarks to unexplained jargon. Frank Versraete is a highly regarded physicist and knows what he’s talking about - but unfortunately, physics professors are not always the best people to explain physics to a general audience and, possibly contributed to by this being a translation, I thought this book simply doesn’t work. A small issue is that there are few historical inaccuracies, but that’s often the case when scientists write history of science, and that’s not the main part of the book so I would have overlooked it. As an example, we are told that Newton's apple story originated with Voltaire. Yet Newton himself mentioned the apple story to William Stukeley in 1726. He may have made it up - but he certainly originated it, not Voltaire. We are also told that ‘Galileo discovered the counterintuitive law behind a swinging o...
Post a Comment
Read more

How to Keep a Plane in the Sky - Alex Davies ****

If there's one big gap in the science writing sphere, it's popular engineering (you can quibble over whether engineering is science, but where else would you put popular engineering?). Alex Davies does the field a real service with this insightful introduction to the world of test engineering. The concept is simple. If we build something and sell it, we need to test it to make sure that it won't fail in a way that's dangerous to the consumer. The most obvious example is airliners, which feature at some length, but this applies to everything from cuddly toys to hair straighteners: someone needs to predict what could go wrong and to put the product through its paces to see if it will survive under any reasonable circumstances. When Davies is telling a story of test engineering in action, the book is a delight. He opens with the way that real bears are used to test if bears can get into coolers and trash cans - and the impressive ways these animals can  circumvent human in...
Post a Comment
Read more

On the Equality of All Things - Carlo Rovelli ****

There is a wide gulf between the worldviews of physicists and philosophers. Many physicists present a rather sweetly naive, child-like view of the world, where philosophers bring a distinctly more adult, cynical tone. This being the case, it can be a little worrying when a physicist dips a toe into the philosophical mire. Infamously, in The Grand Design , Stephen Hawking and co-author Leonard Mlodinow told us that philosophy was now dead because science could deal with anything it had previously been needed for. Thankfully, Carlo Rovelli is not trying to do away with philosophy, though it has to be said that when he veers into the topic that physicist's naivety can make it feel like the philosophising of an earnest eighteen-year-old. Take the opening paragraph, which tells us 'electrons and minds, stones and laws, judgements and galaxies do not essentially differ in nature from one another. They are notions that illuminate each other'. I almost expected a Pink Floyd soundtr...
Post a Comment
Read more