Great scientific breakthroughs have often historically been presented to general readers in compelling and accessible ways. In the 21^st century, however, the gulf between what is written for specialists and what is accessible to the average reader is widening, writes Martin Rees.

Darwin’s The Origin of Species, published in 1860, was a best-seller: readily accessible – even fine literature – as well as an epochal contribution to science. But that was an exception. In glaring contrast, Gregor Mendel’s 1866 paper entitled ‘Experiments with Plant Hybrids’, reporting the classic experiments on sweet peas conducted in his monastery garden was published in an obscure journal and wasn’t properly appreciated for decades. Darwin had the journal in his library, but the pages remained uncut. It is a scientific tragedy that he never absorbed Mendel’s work, which laid the foundations for modern genetics.

It’s unlikely that any twenty-first-century breakthroughs can be presented to general readers in such a compelling and accessible way as Darwin’s ideas were. The barrier is especially high when ideas can be fully expressed only in mathematical language: few read Einstein’s original papers, even though his insights have permeated our culture. Indeed, that barrier already existed for mathematical science in the seventeenth century. Newton’s great work, the Principia, highly mathematical and written in Latin, was heavy-going even for his distinguished contemporaries like Halley and Hooke; certainly, a general reader would have found it impenetrable, even when an English version appeared. Popularisers later distilled Newton’s ideas into more accessible form – as early as 1735 a book appeared in France entitled Newtonianism for Ladies.