Mathematicians know two things (at least). Let us call them postulates. The first is that their work should ultimately lead to a more profound understanding of the universe and everything within it. The second is that non-mathematicians frequently struggle to grasp even quite basic mathematical ideas. They shy with fright at the sight of the symbols and equations that are the tools of the mathematician’s trade. Mathematicians attempt to render the second postulate redundant by finding ways of making their subject more attractive, accessible and understandable to the lay reader.

Ian Stewart, a prolific populariser of scientific ideas, confronts this difficulty squarely in Why Beauty is Truth: “The conventional wisdom in popular science writing is that every equation halves a book’s sales. If true, this is very bad news, because nobody would be able to understand some of the key themes of this book without being shown a few equations.”