Book excerpt: "We gravitate toward people like us; it's human nature. Race, class, and gender affect this social identity, but one overlooked factor can be even more powerful: the way we speak. As pioneering psychologist Katherine Kinzler reveals in How You Say It, that's because our speech largely reflects the voices we heard as children. We can change how we speak to some extent, whether by "code-switching" between dialects or learning a new language. But for the most part we are forever marked by our native tongue-and are hardwired to prejudge others by theirs, often with serious consequences. Your accent alone can determine the economic opportunity or discrimination you encounter in life, making speech one of the most urgent social-justice issues of our day. Ultimately, Kinzler shows, our linguistic differences can also be a force for good. For her research reveals that exposure to different languages is beneficial-a paradox that hints at the benefits we can reap from mastering this ancient source of tribalism"--