John Bicheno reviews Daniel Kahneman’s Thinking, Fast and Slow, Allen Lane, 2011.

In this issue with the theme of people there are perhaps only two contenders: Kahneman’s Thinking Fast and Slow, and Liker and Convis’ The Toyota Way to Lean Leadership. We begin here with Kahneman, with Liker and Convis in a subsequent issue.

Kahneman is a Nobel Laureate and ‘certainly the most important psychologist alive today’ according to Steven Pinker. The book is a ‘blockbuster’ read of 500 fascinating pages covering Kahneman and Tversky’s distinguished careers, and numerous experiments. Not directly a book on lean, but surely an essential read by anyone seeking to understand psychology and the quirks of the human mind. Of course, these are topics now in the forefront of lean due to the work of Mike Rother in Toyota Kata and David Mann in Creating a Lean Culture.

The book is in five parts. The first deals with the ‘Two System’ theory of the brain. System 1 is the automatic system and System 2 the effortful system. It is part of the brain’s efficiency to do automatic work in order to free capacity to do deliberate thinking (this is a sort-of Kingman’s equation found in lean scheduling where muri or overload degrades performance, so like Goldratt’s Herbie story the bottleneck should be offloaded.) The problem is that System 1 is sometimes wrong. Answer this one quickly: a bat and ball cost £1-10. The bat costs £1 more than the ball. How much does the ball cost? If you answered 10p this was System 1 at work, giving the wrong answer. The importance for lean, I think, is that such automatic thinking can seriously mislead by believing WYSIATI (what you see is all there is). How many defects, accidents, deaths?

Part 2 is about Bias. We all have bias in our thinking, and when combined with repetition (Rother’s Kata) very powerful beliefs and behaviours become established. The many kinds of bias are described in numerous experiments. For example, anchoring bias occurs when, if a random number is externally suggested, the human brain unconsciously anchors decisions around it. Disturbing! Confirmation bias is, I think, particularly important in lean. This is where the brain quickly latches on to even weak evidence that confirm prejudices but tend to dismiss or very critically examine events that do not agree with one’s views. This is the challenge of change management. So forget the notion that a one-off piece of evidence will lead to change. It will not, unless it is very significant like 9/11. For example, John Darlington and Kate Mackle have pointed out in this journal the unsuitability of traditional value stream mapping in some manufacturing environments. But this often gets a hot reception. It takes Kata to change.

Part 3 deals with overconfidence, and Part 4 with pitfalls in choices and decisions. As I read, I was horrified at my own ignorance in these areas, both of which have significance for lean.

I hope I have whet your appetite!