From the book:
My former partner Rich Silverstein used to talk about effective advertising using the analogy of those dot-to-dot games we all used to play as children. I'm sure you remember joining numbered dot to numbered dot, trying to guess what you're drawing as the picture slowly emerges. Dot, to dot, to dot... then, with just one stroke of the pencil, it is suddenly clear. You have a picture of a badger. Silverstein always used to say that it was important for us to join enough of the dots in our advertising to avoid confusion (and as a result rejection), but to leave enough dots for the viewers or listeners to join for themselves. Into the gaps between the dots of advertising they should insert their own experience, hopes, fears, joys and sorrows, and thus embrace the communication by becoming a part of it.
I like that. It's an interesting way to think about it. Oh, and so far, the book is really good. You should buy it.