Why do we make colossal errors based on gut instinct? The Undoing Project is the bravura story of the groundbreaking work of two psychologists, Daniel Kahneman (whose Thinking, Fast and Slow has sold over a million copies) and Amos Tversky, whose research into our irrational decision-making challenged fundamental beliefs about who we are. Michael Lewis is a bestselling phenomenon: Flashboys (292k worldwide) was a no.1 Sunday Times bestseller; The Big Short (229k worldwide, Sunday Times Top 10 bestseller) is now a major, Oscar- and BAFTA-winning motion picture. From baseball to banking scams to financial bubbles, their theories underpin everything Lewis has written about: the result of eight years' research, this is the culmination of his work so far.