This wily test of intelligence and mindfulness is defined by two characteristics. The first is that most people fail it; the second is a subtle trick intentionally implemented to catch careless thinking (the schoolgirl for example). Narratives in literature and film that incorporate this test go something like this: scores have tried and failed because they overlooked the trick – even though they confidently believed they did not – until one day a hero catches it and passes the test (Edwards). Game of Thrones readers may recall the moment Syrio became the first sword of Braavos. Unlike others before him, when the Sealord asked Syrio about an ordinary cat, Syrio answered truthfully instead of sucking up. (The ending of Indiana Jones and the Last Crusade also comes to mind, but this does not fit the narrative for a critical reason. Those who failed did not live under the mistaken belief that they succeeded – they were beheaded.)

Here’s my worry. The same thing occurs when lay audiences read books about thinking errors. They understand the errors, but don’t notice the trick – that simply learning about them is not enough. Too often, readers finish popular books on decision making with the false conviction that they will decide better. They are the equivalent of Edwards’ competition – the so-called best of the best who miss the ruse.

The overlooked reason is that there are two components to each bias. The first is the phenomenon itself. Confirmation bias, for example, is your tendency to seek out confirmation information while ignoring everything else. The second is the belief that everyone else is susceptible to thinking errors, but not you. This itself is a bias – bias blind spot – a “meta bias” inherent in all biases that blinds you from your errors.