Ian McEwan on the feeling the writer should create in the reader.
Also, on what makes him able to write: "I suppose it just so happens that the woman I love happens to be my wife, and that is a piece of luck. That creates a sort of stability and a sort of endless interest. I know there are other writers who need the kind of spur of unhappiness to work, but not me. When I'm unhappy I can't work."
ADDED: (Via reader email.) "This is the nature of empathy, to think oneself into the minds of others. These are the mechanics of compassion: you are under the bedclothes, unable to sleep, and you are crouching in the brushed-steel lavatory at the rear of the plane, whispering a final message to your loved one. There is only that one thing to say, and you say it. All else is pointless."