People are born with some innate cognitive differences, but those differences are eclipsed by early achievement, Boaler argues. When people perform well (academically or otherwise) at early ages and are labeled smart or gifted, they become less likely to challenge themselves. They become less likely to make mistakes, because they stay in their comfortable comfort zone and stop growing. And their fixed mindset persists through adulthood. The simple and innocent praising of a smart kid feeds an insidious problem that some researchers track all the way up to gender inequality in STEM careers.

So ending the reign of the S word, as Boaler calls it, is a grand mission. “It’s imperative that we don’t praise kids by telling them they’re smart,” she argued in a Monday lecture to an audience that received her message with many knowing nods. “You can tell kids that they’ve done something fantastic, but don’t label them as smart.”