In a Nutshell
Allow me to transport all of us to the Paris of 1900— La Belle Epoque—when the city fathers of Paris approached a psychologist named Alfred Binet with an unusual request: Could he devise some kind of a measure that would predict which youngsters would succeed and which would fail in the primary grades of Paris schools? As everybody knows, Binet succeeded.In short order, his discovery came to be called the "intelligence test"; his measure, the "IQ." Like other Parisian fashions, the IQ soon made its way to the United States, where it enjoyed a modest success until World War I. Then, it was used to test over one million American recruits, and it had truly arrived.From that day on, the IQ test has looked like psychology's biggest success—a genuinely useful scientific tool.
What is the vision that led to the excitement about IQ? At least in the West, people had always relied on intuitive assessments of how smart other people were.Now intelligence seemed to be quantifiable. You could measure someone's actual or potential height, and now, it seemed, you could also measure someone's actual or potential intelligence. We had one dimension of mental ability along which we could array everyone.
The search for the perfect measure of intelligence has proceeded apace. Here, for example, are some quotations from an ad for a widely used test: