“Human intelligence,” the cultural critic Neil Postman once wrote, “is among the most fragile things in nature. It doesn’t take much to distract it, suppress it, or even annihilate it.”

The year was 1988, a former Hollywood actor was in the White House, and Postman was worried about the ascendancy of pictures over words in American media, culture and politics. Television “conditions our minds to apprehend the world through fragmented pictures and forces other media to orient themselves in that direction,” he argued in an essay in his book Conscientious Objections. “A culture does not have to force scholars to flee to render them impotent. A culture does not have to burn books to assure that they will not be read?.?.?.?There are other ways to achieve stupidity.”

What might have seemed curmudgeonly in 1988 reads more like prophecy from the perspective of 2024. This month, the OECD released the results of a vast exercise: in-person assessments of the literacy, numeracy and problem-solving skills of 160,000 adults aged 16-65 in 31 different countries and economies. Compared with the last set of assessments a decade earlier, the trends in literacy skills were striking. Proficiency improved significantly in only two countries (Finland and Denmark), remained stable in 14, and declined significantly in 11, with the biggest deterioration in Korea, Lithuania, New Zealand and Poland.