The reader already knows more about him than Isabel was ever to know, and the reader may therefore be given the key to the mystery.

What kept Ralph alive was simply the fact that he had not yet seen enough of the person in the world in whom he was most interested: he was not yet satisfied.

There was more to come; he couldn't make up his mind to lose that.

He wanted to see what she would make of her husband--or what her husband would make of her.

This was only the first act of the drama, and he was determined to sit out the performance.