I think there's a very fine line between plagiarism and inspiration.
For example, I remember a few years ago when JK Rowling went to court with a Swiss (I think, but don't quote me on that) writer who had written a book very similar to Harry Potter. The main character of this new book was a young orphaned boy with a scar on his head who discovers he is a wizard and goes off to school at a private academy for wizards and witches with his two best friends. He also plays sports on broomsticks. Sound familiar? I'm not sure if JK Rowling won the case--my guess is she did. If I remember correctly, it was almost exactly the same, except for names and a few minor details-- but I think it's a fairly clear-cut case of plagiarism.
But then take Vladimir Nabokov's Lolita . Few would consider accusing him of plagiarism in this case. After all, who, prior to the 1950's had written such a novel? Pedophilia was only just becoming an issue that people were aware of. But as it turns out, someone did. Nearly twenty years before Lolita was written, a German writer composed a short, forty page story about a man who falls in love with a young girl named Delores. Noticeably, Delores is also the real name of Lolita in Nabokov's novel. But does taking a forty page short story and turning it into a developed 457 page novel following the descent into madness of the main character, constitute as plagiarism? Nabokov was undoubtedly aware of this earlier story, he in fact mentions the title in one of his notes from writing the story.
You might say that it was plagiarism of a great sort. But is it really? In the novel, Nabokov (writing as Humbert) writes, “Only the other day we read in the newspapers some bunkum about a middle-aged morals offender who pleaded guilty to the violation of the Mann Act and to transporting a nine-year-old girl across state lines for immoral purposes” . In this case, he is actually referring to a real life event in 1948 (even though the story is set in 1947). The incident he was referring to, was the of a twelve year old girl named Sally Horner by Frank La Salle, a 50-year-old car mechanic. Horner spent 21 months living and traveling with La Salle before she confided her secret to a friend in Dallas, Texas, where she attended school, and was rescued by the FBI. Lolita and Humbert spend almost a year traveling across the US in his car. The story of Sally Horner was reported through several articles in newspapers across the US, which Nabokov undoubtedly would have read-- if not at the time, then later while researching his novel.
But is this plagiarism also? I'm inclined to say it isn't because Sally Horner was a real person, not a fictional character created by another author, and the real world is fair game to anyone writing. You can't put a copyright on life. But is the newspaper article really that different from the short story? Both existed prior to the novel, and both were read by the author... but the author has developed his story much further than either.
Is it all right to take an idea or a premise from something you read and write your own story of it? How much further does one need to develop an idea before it stops being plagiarism? Can an author even have an original thought anymore? One can’t imagine something that they’ve never experienced before. I’m not saying everyone just copies other people’s work, don’t get me wrong. But certainly someone has to have had something to inspire a certain idea or imagination. They don’t come from nowhere, they are unconscious alterations to something previously experienced. Lock a person in a room from birth and then let them out after twenty years. They won’t be able to imagine angels, nuclear weapons, giraffes, even mirrors, without exposure to other ideas. The human brain simply can’t work like that. If it did, it wouldn’t have taken ten thousand years to develop electricity. We had to spend years building on the conjectures of those before us before people even realized it was possible.
I was going to write more, but then I realized that this is already horrendously long, much longer than I intended, and I’m starting to ramble now. So I’m going to end it here and see how people respond.