The trouble with communication is that we all assume we’re good at it. Occasionally, we are. A friend in need reaches out: we say just the right thing. Smiles all round. Often, we’re not. Christmas dinner: discord descends. Turkey, flung. When the journalist Charles Duhigg was tasked with managing a project at the New York Times, he was surprised to find himself struggling to connect with members of his team. As a reporter, he was speaking to people every day – he was in the very business of communication. Yet he kept having clashes. For some, it wouldn’t warrant further thought. People bicker, right? But for Duhigg, whose books The Power of Habit and Smarter Faster Better probe the science and psychology of everyday behaviour, social shortcomings are like catnip. As he observed these conflicts – first at work, and then at home when he’d complain fruitlessly to his wife, “My boss is a jerk… My colleagues don’t understand me…” and then bicker with her about it all over again – he became curious about …