I believe we live in a universe governed by laws of causes and effects even though we don’t yet fully understand all the causes and all the effects. When it comes to art, in particular, it is immensely difficult to know what cause will result in which effect. So it is tremendously difficult in the realm of words to know which sentence, which metaphor, which plot device will resonate with a majority of your targeted genre’s readers and turn a bunch of words into a great story. Though we don’t know these things with precision, I do believe that there are quantifiable causes and effects in play.
Wired for Story is Lisa Cron’s assertion that we do in fact have (some) science in the realm of writing that enables us to understand the causes and effects of good storytelling.