Around the time I started working in trade publishing, Stephen Hawking's "A Brief History of Time" was a huge bestseller, clocking sales at record rates. I was impressed, and still am, but my thinking on what these numbers meant was altered by the comment of a colleague: "Just because people are buying the book, doesn't mean they're reading it."
And, of course, it's true. Hawking's book was a trendy intellectual purchase. Drop a copy of this much-talked-about dense and brainy bestseller on your coffee table, and guests were sure to gain a favorable impression of your erudition. But speak knowledgably about black holes, quarks and antimatter? Mere ownership of the tome did not such conversations guarantee.