Have you ever tried to finish a tricky but familiar task – unlocking something, let us say – and discovered that, even though the key won’t turn in the lock, and there are other keys to be tried, you’re oddly compelled to carry on jiggling the one that doesn’t fit? If you have, then you have been demonstrating what psychologists call the Einstellung or set effect, which finds that a general tendency exists, in humans, to favour first ideas in problem solving at the expense of alternatives, even when the alternatives are simpler and even when we think we’re looking for them. The Mechanism of the Einstellung Effect: A pervasive source of cognitive bias (2010), by Merim Bilalic, Peter McLeod and Fernand Gobet, considers this phenomenon as it applies to expert chess players attempting to reach “smothering mate”, but it has a wider resonance (for The Neuromantics, and not just for us) in politics, religion, philosophy and daily life – anywhere, in fact, where a predisposition to think one thing gets in the way of new evidence, and so stops us reappraising the situation. The application to literature is equally revealing, and the beautiful work of the American poet D. Nurkse (in his 2013 collection A Night in Brooklyn) shows how riddles and dream narratives make use of cognitive bias to surprise – and delight – the reader.