The plan with three brains
This month Daniel Kahneman turned 80. Long revered among experts in the decision sciences, his work reached much wider public attention with the publication of the bestseller Thinking Fast and Slow.The central tenet of the book, what he calls a ‘useful fiction’, is that we obviously have more than one way of thinking. The ‘fast’ way — imagine answering ‘What is two plus two?’ — is unconscious, effortless, decisive and fast. The second — ‘What is 17 times 34?’ — is conscious, effortful, dithery and slow. There’s nothing new about mental dualism, of course. But what is useful about Kahneman’s simple model is that he names them neutrally ‘System One’