"What I like in a good author is not what he says, but what he whispers." - Logan Pearsall Smith

I think this quote means that a good author can convey his point without directly saying it. It reminds me of the "showing not telling" method that we are told to try using. Smith might mean that what he likes in an author is the less obvious meanings or messages that he can infer from context because the author has given enough description and imagery.