Humans are storytelling machines. We don’t passively perceive the world – we tell stories about it, translating the helter-skelter of events into tidy narratives. This is often a helpful habit, helping us make sense of mistakes, consider counterfactuals and extract a sense of meaning from the randomness of life. But our love of stories comes with a serious side-effect: like all good narrators, we tend to forsake the facts when they interfere with the plot. We’re so addicted to the anecdote that we let the truth slip away until, eventually, those stories we tell again and again become exercises in pure fiction.