In his new bestseller, David and Goliath: Underdogs, Misfits, and the Art of Battling Giants, Malcolm Gladwell looks at what happens when ordinary people confront powerful opponents. He starts the book by dissecting the classic tale of David and Goliath, challenging our beliefs about what the story tells us regarding underdogs and giants, and ultimately, our fundamental assumptions about power. Wharton management professor Adam M. Grant recently interviewed Gladwell about his new book when he visited campus as a guest lecturer in the Authors@Wharton series. Gladwell shared why he never roots for the underdog, where he comes up with the ideas for his books and sets the record straight on the biggest misunderstandings about his work. An edited transcript of the conversation follows. Adam Grant: Let’s start talking about your latest blockbuster: David and Goliath . What’s the core message and idea?…