What is the main idea in the nonfiction book, Whistling Vivaldi?

In Chapter One, An Introduction, At the Root of Identity, Steele introduces the readers to the main ideas of the book, as well as to himself. He talks about his childhood in mid-1900s Chicago, and how he first became aware of discrimination because black families were only allowed to use the pool on Wednesdays. He then describes the concept of stereotypes, and how they can affect people in less tangible, but still just as harmful, ways. He describes a study he performed that lead to the development of the term “stereotype threat,” because in it, he was able to impact black and white students’ performance on a golf exercise just by changing how he described it.