So last year when I was writing The Seal of Karga Kul, I came up with this swell scene involving a collapsed bridge -- Iban Ja's Bridge -- magically held together, spanning a gorge thousands of feet deep and ending in a highland road that cut through a forest and quickly up into broken territory and then mountains. The scenes around that bridge and right after the characters cross it were some of my favorites in the book.
Then a couple of days ago I was reading C. S. Lewis' fourth Narnia book, The Silver Chair, to the kids, and we got to the part where Eustace and Jill, with Puddleglum, see the giants' bridge...which is ancient and partially collapsed...and spans a gorge thousands of feet deep...and leads into broken highlands...
The descriptions in The Silver Chair even sounded oddly like my recollection of how I narrated the Iban Ja bits, or imagined them while I was writing. It's striking, how persistent some submerged influences can be.
It's also striking to have your 9-year-old son read a book you wrote and be mad at you because you killed his favorite character--as it happens, at Iban Ja's Bridge. When I had read the giants' bridge part in The Silver Chair, I looked at him and said, "Man, that's Iban Ja's bridge, isn't it?" and he said, "Yup." Then he yelled at me for killing his favorite character again.
Even the stuff you think you made up, you probably didn't make up.