This summer you’re invited to join with the three specialist teams within HRW, HRW Shift (Behavioural Science), Innovation, and OR:BIT (oncology) are each selecting a book to read during June, July, and August. The month after each are sharing their thoughts in a book review blog. We start with the HRW Shift Behavioural Science team and their review of ‘Predictably Irrational’ by Dan Airely

Summer Book Club: HRW Shift Predictably Irrational

I have to say, as far as homework assignments go, this was a pretty fabulous one. I spent a lot of it in the park, Allie on the beach, green-fingered Emma in her (green) house while Katy elected the audible route completing her reading on the run unconstrained by space or time… well, perhaps not quite, but close to.  Over the last month the HRW Shift team have been re-reading Dan Ariely’s Predictably Irrational. And we’re all in agreement it’s just as great the second time round.


Predictably Irrational is a great place to start exploring behavioural science if you’re new to the field. Unlike other classics, such as Daniel Kahneman’s Thinking Fast and Slow, this one is determinedly accessible. Ariely maintains a pop-psychology feel without compromising on the integrity of data. Where Kahneman describes his book as being a set of anecdotal experiments for ‘water cooler conversations’, Ariely leaves you feeling like you’re absorbing incredible insights into the human psyche and thinking about how you can re-adjust and incorporate this new understanding into your life.


What’s it all about? – bringing the science to life



At the heart of this book are the numerous, tangible examples that bring the science to life. Essentially, Ariely’s manner of storytelling brings you on a journey with him, so you’re not just listening to what happened, you’re imagining the curious taste of balsamic vinegar in beer. And who could forget stories of literally lining up for an exercise in sleep deprivation reminiscent of SAS interrogation torture techniques, camping out night and day just for a basketball ticket?! Or students masturbating and answering surveys in hot emotional states? What about reliably choosing Hershey’s chocolate over Lindt (… yes, Hershey’s. Over Lindt. What insanity is that?!!). Ariely adeptly draws you in, freely sharing his own stories that are clearly personal, sometimes painful and always interesting, while simultaneously inviting you to examine your own life, behaviours and decisions you make. You’re artfully challenged to consider the extent to which your own behaviour is shaped by external factors, and even gently question your own self-concept – what would I do in that scenario? Would I cheat too?

We know the human mind loves a good story, and my goodness, that’s what he feeds us, solid facts couched in real world results and examples. If we’re totally honest some of the examples were, at times, a little belaboured, but we’ll ‘Pratfall effect*’ forgive Ariely that one.

*’pratfall effect’ is when something is considered more compelling when there is one obvious drawback or flaw.


Why it works so well? – we’re only human after all

Perhaps one of the most critical components that makes the book so compelling is the absence of any judgement when it comes to human behaviour. At no point is there any sense of shame or reproach, which could be easily associated with things that appear to violate social norms. Ariely balances teasing apart behaviour with illustrating just how hard it is for us to really think and see outside of ourselves. The result serves to make observations more palatable when discussing behaviour that could be distasteful or uncomfortable in less skilful hands. Whether discussing unprotected sex, cheating on tests, or a lack of self-control, Ariely’s narrative voice comes across as genuinely interested in understanding human behaviour without making any moral judgement.



Ariely’s analysis of the hot-cold empathy gap (our tendency to underestimate the influential power of physical states on our behaviours, attitudes, preferences and predictions, particularly in the ‘heat of the moment’) is a prime example of this non-judgemental tone. Ariely uses the example of unprotected sex to illustrate that in the heat of a moment of passion with another, many of us will at some point have found ourselves ‘caught out’ without protection. In that moment most will have experienced the internal tension between two opposing forces being brought into conflict, one the desire to throw caution to the wind, the other recognising the importance of acting safely. The choice that was made at the time is irrelevant, what is important is that by taking us, the reader, along this journey we come to see that other people’s behaviour is no more or less rational than our own. It is more that we all behave less ‘rationally’ than we tend to think we do, and this dynamic is subtly played with throughout the book.

Finally, while compiling all of these intriguing insights Ariely also tries to find solutions to these real world matters, providing suggestions and ideas so you’re not left with the impression of a host of problematic human behaviours, and no suggestions as to what to do with this newfound insight. Some of these suggestions are more applicable to everyday life and practical than others, others still are focused more on the ‘big picture’ and policy change. The point is that while he does try to find real world solutions, he does so without coming across as pretending to have all the answers.


The crux of the critique

But, as no self-respecting review is complete without some form of constructive critique (if you’ll forgive us Professor), this leads us on to where we become slightly unstuck. While great and effective effort is made to ensure the presence of this hallmark openminded tone throughout, the title itself gives away that the whole book is in fact rooted on an evaluative judgment. Early on it states, “This journey into the many ways in which we are all irrational, then, is what this book is about”.



At HRW Shift we’re of the perspective that not everything non-conscious should be considered ‘irrational’. The biases that sway our behaviour have evolved over thousands of years’ and are adaptive, they exist to make the best use of limited mental resources, brain energy is finite after all, and like all precious resources it needs to be preserved and allocated appropriately. Ariely sets up the dichotomy of what the rational choice should be, and contrasts it to the ‘irrational’ one. Throughout, the inclination to make ‘rational’ decisions under various circumstances is tested and it’s concluded that accounting for these tendencies to behave ‘irrationally’, and adapting your behaviour accordingly, would probably give you a better experience on your travels through life by virtue of making ‘better’ decisions.

Ariely states: “I suspect that over the next few decades real improvements in life expectancy and quality are less likely to be driven by medical technology than by improved decision making” and perhaps this is the case. However, we think it’s important to keep in mind the broader context when we consider what exactly is meant by ‘irrationality’.


What exactly is ‘rational’ anyway?!

Definitions of rationality are profoundly contested and necessarily demand a value judgment made about what decisions ‘ought’ to have been chosen. When we think about the field of behavioural science, especially behavioural economics, we cannot forget that this field remains heavily dominated by white men fitting the WEIRD definition to the letter. That is, they come from a Western, Educated, Industrialised, Rich, and Democratic background – a demographic skew which gives a very specific lens to our interpretations of the world and behaviour. We must also remain conscious that the research subjects from which Ariely draws his examples in the book are also skewed in the WEIRD direction. Namely, most appear to be MIT or Harvard students! Who is to say that this narrow group has the optimal view on what decisions ‘ought’ to be made.



We witness the danger of drawing sharp lines around ‘rational’ and ‘irrational’ choices everyday as researchers in healthcare. For instance, we often see a tension between the relative value of quality of life over quantity of life achieved through impeding disease progression, so taking this as an illustration: The physician’s ultimate agenda is to make sick people better (at least, one would hope!). But so often we hear first-hand from patients how their quality of life (QoL) is such a vital factor for them, yet they feel this component can be overlooked by their doctor. Meanwhile Physicians use tests and lab results to determine if a patient’s condition is stable or in remission, and if these numbers move in the right direction they’re happy, content they’re meeting their goals to the best of their ability.

From the Patient’s perspective, what use is another six months, five years’ or even ten if the disease or the side effects leave them bedbound due of fatigue, housebound because of self-consciousness, or fretting if they’re more than ten meters from a bathroom. What use is this time if your QoL is so poor you feel robbed of the ability to enjoy it? Is the patient then irrational for being willing to shorten their life expectancy in exchange for a more enjoyable ride? – presumably not. Is the doctor irrational for focusing on the control and management of a disease above all else and possibly considering a patient that turns down further life preserving treatment foolish… or irrational? – again, presumably not.

The point is that there is more than one dimension to ‘rationality’ and by virtue of this, what qualifies as ‘irrational’ is also subject to interpretation. Fundamentally, what we see throughout the book is one perspective of what constitutes rationality and irrationality – granted an intelligent, well-educated one – but one perspective nonetheless. Ariely evaluates and proclaims rationality over irrationality but who is to say this one interpretation of rationality is ‘correct’ or ‘right’ above all others?

But! Before we fall too far through the looking glass, when all is said and done it’s still a thoroughly enjoyable, accessible, and informative read. So for anyone looking for an easy way into a better understanding of behavioural science, Predictably Irrational is a pretty good place to start!

For more information on HRW Shift behavioural science expertise get in touch!

Next month, join the HRW innovation team in reading their selection in the summer book club: Everybody Lies by Seth Stephens-Davidowitz


Words by Rhiannon Phillips

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