Cryptomnesia

I fear Cryptomnesia- the scary-but-true phenomena where you can steal somebody's work without realizing it!
After he wrote Treasure Island, Robert Louis Stevenson discovered that he'd borrowed details (the parrot, the skeleton-as-pointer, some settings) from older works, even though, when he wrote them, "they seemed to belong to me like my right eye."
More recently, a popular novel was yanked from bookstores* when people discovered it lifted sentences from other works. The author claimed it was an accident. "Aw C'mon," critics snipped, " How do you accidentally steal an entire sentence...!?"
...but it can happen.
I think it works like this.
I see (or hear) Work X (a story, a movie, an expression etc...). Time passes. My brain remembers some details, but not the I saw this before detail. Reverse deja vu. I think it's mine. I incorporate it into my work...
...and someone notices that my masterpiece sure looks a lot like Work X.
Suddenly I'm a hack. A thief!
Am I cranking out other people's work as my own!? Too bad Blogger doesn't have a "plagiarism check" along with the spell check.

p.s. for the record, the background text in the picture isn't mine.

*the movie deal ended about this time too.