The Undoing Project

Amos Tversky and Daniel Kahneman were two Israeli psychologists whose work revealed patterns of human irrationality, particularly the ways that our minds consistently fool us. They used the word ‘heuristics’ to describe the rules of thumb that often lead people astray, and investigated cognitive biases. One such rule is the ‘halo effect’, in which thinking about one positive attribute of a person causes observers to perceive other strengths that aren’t really there. Another is ‘representativeness’, which leads people to see cause and effect — to see a ‘narrative’ — where there is only randomness. Evidence from their work has underpinned a whole new science of behavioural economics.

The Undoing Project is the story of the collaboration between Tversky and Kahneman and the significance of their work. They were both grandsons of rabbis from Eastern Europe, and both were deeply affected by their service in the Israeli military — including in the Yom Kippur War of 1973. Tversky’s panache made him the more prominent of the pair, and helped them challenge the orthodox in academic psychology. Kahneman’s humility made him unsparingly self-critical, which allowed him to diagnose widespread human errors that others had missed. Kahneman came to realize that when he was faced with results from studying 40 subjects, a typical sample in psychology, his instinct was to devise an explanation for the results. In truth, the most likely explanation was statistical noise. A good example is the following. Ask someone to write down the results of an imagined sequence of 20 coin flips. Then ask the person to flip a coin 20 times and write down the results. The actual flips will almost certainly contain long streaks of only heads or tails — the sort of streaks that people don’t think a random coin produces on its own. This kind of misconception leads us to misanalyse all sorts of situations, in business, politics and everyday life. Lewis, describing one of Kahneman and Tversky’s real-life disciples, writes, ‘He suggested a new definition of the nerd: a person who knows his own mind well enough to mistrust it.’ Read this book and make your own judgement about it, in so far as you can trust it.

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368 pages in Allen Lane

First published in 2016

ISBN  978-0241254738



Michael Lewis

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