At least when Tony Blair intoned that “a new dawn has broken, has it not” a few short hours after his election victory on the night of 1 May 1997, it was actually dawn. These days the metaphors emanating from 10 Downing Street seem to bear less and less resemblance to reality. Boris Johnson, our leader in this crisis, evokes men on horses, bugles tooting, a veritable cavalcade of military metaphors to keep us chipper as we wait to be vaccinated. For the health secretary, Matt Hancock, echoing Blair, “the light of dawn is on the horizon”. This apparently means “it’s the moment to stand firm until morning so we can look back and see clearly that everything we gave was not for nothing … but so we could build back better for everyone.” Look closer, however, and you’ll see a front of mixed metaphors rolling in alongside clouds of obfuscation. It’s not that metaphor itself is the problem. In fact, it’s virtually impossible to communicate without metaphor. As the psychologist Lisa Feldman Barrett writes in her new book, 7 ½ Lessons About the Brain, the ability to pick out similarities among very different objects or experiences is what separates us from the rest of the animal kingdom. Indeed, metaphors are so common that the various figures of speech we use mostly fade into the background – just like that one there. But when a metaphor leaps out at you it’s a sign that something’s up: either a brilliant new insight, or a cringeworthy attempt to convince. Johnson’s tooting arguably falls into the latter category. There’s something condescending about peppering your speeches with martial banter when most people are looking for straight talk. The contrast with Johnson’s hero, Winston Churchill, is notable. Erik Larson, in his recent study of the latter’s leadership during the blitz, tells us that Churchill would always begin speeches “with a sober assessment of the reality of the threat – and he would not sugarcoat. He would state as frankly as he could what was actually happening, but then he would follow with … realistic cause for optimism. Not happy talk, but a rational appraisal.” Which is not to say the occasional overblown metaphor can’t be charming, or even offer some much-needed comfort. Enter the deputy chief medical officer for England, Jonathan Van-Tam, the unlikely hero of the moment, whose clear explanations of what we are facing are spiced up with unexpected yet endearing metaphors. They are not meant to impress or to rouse, just to better enable us to understand what is going on. Early in November, amid jubilation over the first vaccine efficacy results, Van-Tam transported listeners to a rainy platform somewhere far from home. “This, to me, is like a train journey where you’re standing on the station – it’s wet, windy, it’s horrible – and two miles down the tracks, two lights appear and it’s the train. And it’s a long way off.” On BBC Breakfast on Thursday he revealed that, like any good science communicator, he had been honing his skills for some time. “Many years ago,” he said, there was a lance corporal who used to ask him medical questions “as they sat around in tents in Snowdonia”. That was where Van-Tam “practised the art of turning medicine into stories”. He has engendered such a level of trust that his stories, unlike Johnson or Hancock’s, are very likely to be believed by a large number of people. Experts, it seems, are back in fashion. The latest service announcement from Van-Tam is unlikely to reverse that trend. “The train,” he said on Wednesday, “has now slowed down safely, has now stopped in the station. And the doors have opened.” David Shariatmadari is the author of Don’t Believe a Word: From Myths to Misunderstandings – How Language Really Works