‘Trillions’ doesn’t add up
‘Oh no, darling’ said my husband, stirring from torpor in his armchair, ‘only about seven ounces of you is bacteria – about the same amount as those little bottles of milk we had at school.’ I had been talking about billions, trillions and quadrillions and had suggested that our bodies’ cells were outnumbered ten to one by bacteria. But since 2016, apparently, the reliable estimate is of 30 trillion human cells with 38 trillion bacteria wandering about inside us. The language of those large numbers remains ambiguous. In 1974 Harold Wilson, the prime minister, refused a request by a Tory MP for ministers to use billion only in its British
