Fairy Tales

I think his point is that the consequence doesn’t logically follow from the action (or inaction). That is to say, there’s no reason that opening a box should bring evil into the world—the logical consequence is that the box is open. Yet, in the myth, it does bring evil into the world.

It’s the same thing with the flower in “Beauty and the Beast.” The father picks a flower—so that means his life is forfeited to the Beast? What sense does that make? 

I think his point is largely the same as yours, then: to understand the fairy-tale, we have to accept the incomprehensible condition. In context, he’s comparing this kind of “liberty” to one Yeats proposes and finds that “elfin” liberty is not lawlessness because it’s bound by this incomprehensible conditionality. 

As for the Bible and fairy-tales, I’m not sure. He was, obviously, a Christian apologist, but he wasn’t a biblical-literalist (nor was Lewis). He might have believed that much of the Old Testament were stories designed to express truths, rather than to record history, something with which Lewis probably would have agreed.