"Along the way, about certain things, you realize, "I don't know anything about this." You think, "Is this going to sound ridiculous?" So I pestered more than a hundred different people over the course of the book. And when I finished the book I gave it to six or seven trusted readers, who are always the same, but I also gave it to a brother of mine who's a doctor and I asked him to read it, and he was very helpful. It's good to have a group of trusted readers. As my kids have grown up, they've joined this group."

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