Gladwell states that his objective in Chapter 3 is to examine the role of talent or ability in success (after focusing on opportunity in the first two chapters). He first introduces Chris Langan, who has perhaps the highest IQ of anyone alive today, and then backs up to tell the story of researcher Lewis Terman, creator of one of the most used IQ tests in the US. The purpose here is to examine how much intelligence alone leads to success. After World War I, Terman began what would be a 50-year study of children identified as having high IQs. After selecting his cohort, he followed them throughout their lives. It turned out that not all were as successful as their level of intelligence suggested they should be. Most were rather average and some were outright failures. What’s more, two children Terman tested and rejected for his cohort ended up as Nobel laureates.

Gladwell argues that IQ alone is not enough to ensure success. While it is important to have a high enough IQ, once a certain level is reached, the law of diminishing returns sets in. As one researcher put it, “Knowledge of a boy’s IQ is of little help if you are faced with a formful of clever boys” (84).