When it comes to fiction - which today includes television, movies, video games, and other narrative media - copying someone else's ideas is nothing new. The Romans, after all, openly borrowed most of their gods from the Greek pantheon; the Greeks, in turn, clearly adopted and adapted elements from the animistic, agriculture religions that preceded them; and whether by divine fiat or imaginative inspiration, many events recorded in the Christian Bible explicitly echo earlier narratives in the Jewish Torah. Indeed, there is some reason to believe that the stock of basic human narratives is relatively small: in the twentieth century, thinkers as different as Carl Jung, Joseph Campbell, and Northrop Frye each developed interpretive systems based on groups of supposedly universal archetypes or stories like "the shadow" and "the journey home."
One doesn't need to accept Jung's hypothesis of a "collective unconscious," however, to see that sharing, borrowing, or outright stealing someone else's ideas have long been the engines behind narrative evolutions and variations. For a long time in Western culture, moreover, this wasn't a problem. At least from the Renaissance through much of the eighteenth century, "to emulate" was a very positive verb, the key to success both socially and artistically. Of course there were always iconoclasts; Sir Phillip Sidney, for example, could joke in the opening sonnet of his "Astrophil and Stella" sequence that "Other's feet [i.e. lines of verse] still seem'd but strangers in my way," and end with his Muse's command: "Look in thy heart, and write." But of course Sidney didn't invent the idea of a Muse, which means that even his image of inspiration's source was unoriginal!
By and large, it was not until the end of the 18th century that British poets began to prize originality and imagination over mere craftsmanship and wit. Even as he drew on biblical and mythological sources, the Romantic-era poet and artist William Blake articulated the stakes of his determination to be original: "I must Create a System or be enslaved by another Man's." Today's authors - or at least their publishers, and certainly their publisher's lawyers - still claim to put a premium on this kind of originality, for legal reasons if not for Blake's ethical ones. Such statements of originality, ironically, now literally come standard on the copyright page of every newly published novel: "[xxx] is a work of fiction. Names, characters, places, and incidents are the products of the author's imagination or are used fictitiously. Any resemblance to actual events, locales, or persons, living or dead, is entirely coincidental." So please take a moment to admire with me the irony that the insight "Good artists borrow; great artists steal" is variously attributed to T.S. Eliot, Pablo Picasso, and Igor Stravinsky!
Instead of decrying fiction's perennial lack of originality, we should celebrate it. The concept of intellectual property is still important, of course, if only so that writers and artists are fairly compensated for their work. Meanwhile, several strands of literary criticism and theory have recently sprung up to make sense of our copycat culture: "Adaptation Studies," analyzes the various ways narratives, images, and forms cross texts and even media to take on new meanings, often quite subversively; "Intertextuality" focuses specifically on allusions and echoes, intentional and otherwise, that link authors and texts; and "Media Archaeology" examines the history and evolution of forms and technologies of representation, the better to understand where our digital future is taking us.
One of the most common and obvious forms that adaptation takes in our culture today is the jump from book to movie. (There are now entire websites devoted to tracking these connections.) Purists still insist that we must "read the book!" first, and as an English professor I'm not going to argue with this admonition. But what happens when the movie is arguably better than the book on which it's based? This, of course, depends on one's definition of "better" - but if we can agree that "better" in these cases means some combination of more entertaining, more thoughtful, and truer to human experience, then it seems clear that on some occasions, the copy is indeed better than the original. Many of Alfred Hitchcock's best movies, for example, are far more rewarding than the often-obscure source materials on which they're based; more recently, many reviewers agreed that David Fincher's movie adaptation of Gone Girl improved on Gillian Flynn's original novel. For every example of a movie that improves on the original book, however, there are probably five movies that flatten, simplify, or just plain ruin their sources. Indeed, I'm hardly the first person to note that, where creativity on screen is concerned, much of the best work has shifted to TV, where shows like Mad Men and True Detective take risks that Hollywood often can't or won't. Again, though, it's important to distinguish creativity from originality; while these shows have plenty of imagination, they wear their narrative and tonal debts (to mid-century American bildungsroman, in the case of the former; to southern Gothic and noir mysteries, in the case of the latter) on their small-screen sleeves.
Working with - and hopefully, at least sometimes, improving upon - someone else's ideas is not only inevitable, but invaluable. Let's do it honestly, and let's commit to celebrating it when it's done well. But in case you don't like anything I've just written, please remember: Any resemblance to actual events, locales, or persons, living or dead, is entirely coincidental.