The poet TS Eliot wrote that he found a piece of religious writing very moving not because of the quality of its faith, but because of the quality of its doubt. It is a shrewd observation. Scientists, too, are good at doubt. They look at the world and try to figure out, for example, how and why a pandemic affects different people in different ways, or whether a drug treatment really works. Then they formulate a hypothesis and test to see if it stands up to the facts. They sometimes doubt their own results and talk to other scientists expecting constructive criticism before reaching a conclusion. This simplification of the scientific method is hugely important in our lives. On coronavirus, governments all over the world tell us that they "follow the science". That’s broadly true, but "the science” – as we are all too aware – is not fixed. It develops and changes. One scientist may consider the conclusions of another scientist to be faulty. Another scientist working on a hunch might make a breakthrough – or maybe it is a false hope. And that is where a new book on science also shakes faith, but in a good way. The book is called <em>Science Fictions: Exposing Fraud, Bias, Negligence and Hype in Science</em>. It begins with a story about some remarkable research that the author Stuart Ritchie came across as a PhD student at Edinburgh University in 2011. He writes about the extraordinary news that a US researcher found students to have psychic powers. As Ritchie puts it: “a new scientific paper had hit the headlines: a set of laboratory experiments on over 1,000 people had found evidence for psychic precognition – the ability to see into the future using extrasensory perception.” Wow! That sounds exciting, especially since the research was by a top US professor at a leading university. A highly motivated Ritchie tried to replicate the experiment. But then he found that his own results "showed … nothing." Ritchie wrote up the results and submitted them to the same journal which published the original research, the <em>Journal of Personality and Social Psychology</em>, but publication was rejected on the grounds that the journal "never publishes studies that repeat a previous experiment", even in this case when the new study suggested the previous study might in some way be flawed. Ritchie – now working at King's College London – was stunned, and decided to write a book on how science sometimes gets things wrong, and how we cannot always rely on what are supposed to be scientific "facts." As he puts it in an interview with <em>New Scientist </em>magazine: "We think of science as being this objective thing that tells us facts about the world and produces all those scientific papers, which are almost sacred things. But a lot of people don't see how the sausage is made. I think if they had more of an idea of how the process happens, they would question the truth status of those papers a lot more. In a lot of cases the science is useless." Ritchie is not debunking scientific research. He does not lead us into a kind of Trumpland where <a href="https://www.thenational.ae/world/the-americas/coronavirus-trump-claims-disinfectant-comments-were-sarcasm-1.1010597">quack cures for coronavirus are advanced</a> and scientific facts about greenhouse gas emissions and global warming are ridiculed. But he does identify in his book what he calls the perverse incentives of academic life, the pressure to publish new work, to obtain grants and be rewarded with promotion, publication in prestigious journals and citations in other papers. Research can make headlines and reputations. But what is often not rewarded – and other scientists writing about this field confirm Ritchie’s conclusions – is replication. That is, repeating an experiment (as he did in the psychic precognition experiment) to see if the original findings stand up to scrutiny and to assess whether the findings are statistically significant. This matters. It matters because what scientists say about climate change, coronavirus, bad diets, causes of cancer, pollution and so on, affects all of us. We need to have faith in the enlightenment values of truth and facts that underpin science, and perhaps that means we also have to encourage some of the more boring research that does not make headlines and which nevertheless offers a corrective to all those news-making stories about the wonderful health-giving properties of broccoli or olive oil or chocolate or whatever might be the diet fad of the day. Perhaps the new motto of science should be that old phrase of former US president Ronald Reagan: "trust, but verify". Although human nature suggests we are all prone to taking seriously science that stirs our hearts rather than creates doubts. Or as that 17th-century English philosopher of science Francis Bacon put it: “It is the peculiar and perpetual error of the human understanding to be more moved and excited by affirmatives than by negatives.” We all love a good positive story, but sometimes we just need the facts, even if they are boring, and negative. <em>Gavin Esler is a journalist, author and presenter</em>