Sublime

Tetlock leur a donné des surnoms (empruntés au philosophe Isaiah Berlin) qui sont devenus célèbres dans les communautés de la psychologie et du renseignement : les hérissons spécialisés qui « connaissent une chose sur le bout des ongles » et les renards agrégateurs qui « connaissent beaucoup de petites choses ».

“Who experts were—professional background, status, and so on—made scarcely an iota of difference,” Tetlock concludes. “Nor did what experts thought—whether they were liberals or conservatives, realists or institutionalists, optimists or pessimists.” But “[h]ow experts thought—their style of reasoning—did matter.” The critical variable turned out to

Tetlock has studied 300 academics, economists, policymakers and journalists and compared more than 82,000 of their forecasts to what actually happened in the real world. Here are his conclusions:

Management psychologist Philip Tetlock concludes from his research that there is an inverse relationship between the best scientific indicators of good judgement and single-minded specialisation. Drawing from Isaiah Berlin's ‘fox and the hedgehog’ analogy, he contends that the fox – the thinker who knows many little things, draws from an eclectic

In Tetlock’s analysis, the foxes—attuned to a wide range of potential sources, willing to admit uncertainty, not devoted to an overarching theory—turned out to be significantly better at predicting future events than the more single-minded experts. The foxes were full spectrum; the hedgehogs were narrowband.