"Ultimately the product that any writer has to sell is not the subject being written about, but who he or she is. I often find myself reading with interest about a topic I never thought would interest me—some scientific quest, perhaps. What holds me is the enthusiasm of the writer for his field. How was he drawn into it? What emotional baggage did he bring along? How did it change his life? It's not necessary to want to spend a year alone at Walden Pond to become involved with a writer who did" (p. 5).

"Who is this elusive creature, the reader? The reader is someone with an attention span of about 30 seconds—a person assailed by many forces competing for attention. At one time those forces were relatively few: newspapers, magazines, radio, spouse, children, pets. Today they also include a 'home entertainment center' (television, VCR...