As I was growing up in England in the latter half of the 20th century, the concept of intelligence loomed large. It was aspired to, debated and – most important of all – measured. At the age of 11, tens of thousands of us all around the country were ushered into desk-lined halls to take an IQ test known as the 11-Plus. The results of those few short hours would determine who would go to grammar school, to be prepared for university and the professions; who was destined for technical school and thence skilled work; and who would head to secondary modern school, to be drilled in the basics then sent out to a life of low-status manual labour.
The idea that intelligence could be quantified, like blood pressure or shoe size, was barely a century old when I took the test that would decide my place in the world. But the notion that intelligence could determine one’s station in life was already much older. It runs like a red thread through Western thought, from the philosophy of Plato to the policies of UK prime minister Theresa May. To say that someone is or is not intelligent has never been merely a comment on their mental faculties. It is always also a judgment on what they are permitted to do. Intelligence, in other words, is political