According to Gardner, our misjudgments originally stem from the fact that our brains have evolved to deal, very effectively, with the sort of immediate risks that we have historically encountered as a species, say as hunter-gatherers in the African savannah. But it is this same evolution that makes our brains singularly ill-adapted to the complexities of the modern 21st Century urban jungle and causes us to make egregious mistakes.
At the heart of Gardner’s explanation lies the idea that we have two different internal systems to react to events: roughly summarised as ‘head’ and ‘gut’. ‘Head’, a rational, reflective, but also slow-acting system, is often overridden by ‘gut’, a more intuitive, fast-acting system, which bases its recommendations on factors such as precedent and recency. For example, in the case of stressful situations, ‘head’ barely gets a say, and if so, then often too late.
Historically, ‘gut’ has served us very well. The fact that we have a vivid recent memory of an event (say a landslide) colours our perception of the current risk of such an event, which, by and large, highlights the more imminent current dangers.
In a society such as ours, however, where we are constantly bombarded with – in particular – images and stories of extreme, but very rare events, that same ‘gut’ leads us to overestimate the importance of spectacular (but very rare) events, and conversely underestimate the importance of low-key (but common and very dangerous) events.
One of the many striking examples of the book is that this wrong perception of risk led to 1500 extra deaths (another 50% above the original death toll) after 9/11. After being exposed to the incessant coverage of the event, many Americans switched from air travel to road travel. This is apparent from various statistics, such as airline passenger numbers, road toll figures, etc. Unfortunately, when you look at the time series of road deaths in the US, you will see a fairly flat series, except for a pronounced spike in the 12 months after 9/11, corresponding roughly to 1500 excess deaths, which could have been avoided, had these and many other people not been unnecessarily scared by an extremely rare event.
Gardner does a very good job of explaining the various players that reinforce these irrational fears of ours, such as the media, who can only be successful if they produce spectacular stories, and our politicians, who are often most successful by stoking a given fear and then being seen to counteract the perceived danger.
What is particularly useful is the way Gardner explains how seemingly objective ‘facts’ or figures can often be extremely misleading. Thus, for example, the fact that some cancer rates in the West are going up stems from the fact that people are NOT dying from other diseases, living longer lives, and therefore have a better chance to – eventually – be afflicted with cancer.
Another striking example of (irrational) fear is crime rates, which have, in fact, been falling across the board over the last few decades; in particular violent crime, including crimes against children.
Gardner’s book, apart from being a good and fun read, is also fundamentally very reassuring. Essentially, it demonstrates that we have never been as safe or healthy as we are now.