Ian Mcewan said this quote

You pull a book from the shelf and there was an invention... Almost like cooking, I thought sleepily. Instead of heat transforming the ingredients, there's pure invention, the spark, the hidden element. What resulted was more than the sum of parts... At one level it was obvious enough how these separarte parts were tipped in and deployed. The mystery was in how they were blended into somthing cohesive and plausible, how the ingredients were cooked into something so delicious. As my thought scattered and I drifted toward the borders of oblivion, I thought I almost understood how it was done.