Imagine two people own farms. One has very rich soil, full of nutrients, ready to grow amazing crops. The other has thin depleted soil, barely able to support p

Imagine two people own farms. One has very rich soil, full of nutrients, ready to grow amazing crops. The other has thin depleted soil, barely able to support plant life. The farmer with rich soil has the opportunity to out-produce the other one, but only if he works the land. And the harder he works it, the more productive he will be (up to a point). Or think of top athletes. Only a few people have the inborn talent to become Olympic champions. But no one becomes an Olympic champion unless they work hard—no matter how talented. Heritable intelligence is best thought of as a potential. Education can increase a person’s IQ scores for the same reason that working out can increase a person’s athletic performance. We don’t have a way to directly measure inherited potential in people; we can only measure what they do. Even an IQ test is based on what people do as they take the test. But also the idea that intelligence is fixed at birth does not align with what we know about brain development. We know the brain develops through early adulthood, and that different life experiences result in physically different brains. While inheritance may put a top-end limit on how intelligent someone can become, it does not necessarily fix intelligence precisely on the IQ scale at birth.