No matter how good your intentions, you could well be a plagiarist.
Every semester, Southern Methodist University professor Alan S. Brown shows his psychology students how simple it is to become one.
He sits down four of them in front of the class and assigns them a simple task: to take turns listing different animals without any repeats. They start, ''Cow, pig, sheep, goat," he said, and fairly soon, ''someone plagiarizes" -- copies someone else's animal example. It happened just a couple of weeks ago, he said. ''I stopped the student and said, 'You know, you just copied that from someone who said it earlier," and her eyes got real big and she said, 'No, I didn't!' "
Memory experts say they cannot know the individual truths of the plagiarism cases that erupted last week at Harvard, where an undergraduate said she had unconsciously plagiarized from another popular coming-of-age novel, and at
But historical anecdotes abound of otherwise virtuous people who apparently plagiarized inadvertently, from Helen Keller to Sigmund Freud to the Beatles singer George Harrison.
And in recent years, psychology researchers like Brown have begun to experiment with the phenomenon of unconscious plagiarism, which they call ''cryptomnesia," and to get some glimmerings of the forces at work.
When plagiarism cases crop up, said Harvard psychology professor Daniel L. Schacter, ''there's always a dispute about whether it's intentional or unintentional, but what the memory research suggests is that there's a scientific basis for expecting that on some occasions -- we don't know when -- this will be the product of unintentional, memory-based processes."
At work in unconscious plagiarism, Schacter said, is a failure of ''source memory" -- the kind of mix-up about the source of a memory that occurs when, say, you think you heard something from Bill when in fact it was from George, or you think you saw something on TV when in fact you heard it on the radio.
Only it goes a step further: The unconscious plagiarist is not aware that a sentence, phrase, or image is coming from memory at all. They have a ''false feeling of novelty," as Schacter puts it.
Memory theory suggests that we often use our memories without being aware we're remembering, said Richard Marsh, a University of Georgia psychology professor. ''And that's really hard to combat, because if you don't know that you're accessing memory, how can you avoid that error?"
''From that perspective, unconscious plagiarism is a very pernicious problem," he said.
Brown was the first to try to examine cryptomnesia (the name means ''hidden memory") in the laboratory. The experiment, published in 1989, was much like his classroom exercise, asking subjects in four-person groups to list animals, sports, clothing, or musical instruments. He has found that in such tests, subjects tend to plagiarize, or repeat other people's answers, between 8 and 12 percent of the time, he said.
Marsh has published several more recent experiments. In some, subjects were asked to find words in a grid of letters, much as in the game Boggle. After each word they found, a computer would list another word hidden in the grid. When asked later which words they had found, they often claimed credit for words the computer had listed, Marsh said. And when asked to come up with more new words, they often repeated words the computer had found.
In other tests that more closely resemble the real-life problem, Marsh's team tried gathering small groups and asking people to think up ways to improve their university, or to reduce traffic, then brought them back a week later and asked for totally new ideas. About one-fifth of their purportedly new ideas had been given the week before by someone else in the group, Marsh said.
The experiments have turned up some interesting tendencies: Plagiarism tends to be more likely if the plagiarist is the same gender as the source of the original item, for example. Older adults are more likely to confuse source memories than younger people. And plagiarism can be reduced if subjects are encouraged to focus on the sources of their ideas.
Marsh's ''take-home message," he said, is that when people are busy trying to be creative, they tend to fail to consider where their ideas come from and can inadvertently steal. But ''if you do then carefully consider, you can avoid the error."
Thus far, the research does not answer a question that seems central to last week's plagiarism cases: whether copying that involves extensive passages and multiple sentences can be utterly unintentional.
It appears unlikely, said Marsh, because memory theory holds that people don't tend to retain text verbatim; there is just not enough room in memory. Rather, ''when we read, we extract the meaning and dump the text," he said.
But it may be possible, memory experts say.
Some people really do have a better memory for conversation and written text than others, said Brown. ''It may be the curse of an excellent verbal memory," he said.
Consider the case of professor George H. Daniels, a historian who, in 1972, wrote an apologetic letter to the journal Science admitting that he had unintentionally plagiarized in his well-received book ''Science in American Society." As quoted in Brown's 1989 paper, Daniels wrote, ''I have certainly been aware that I had an extraordinary ability to remember material when I wanted to, but I have never before realized that I did it unconsciously."
Contacted last week, Daniels, now 71 and retired from the University of Southern Alabama, said he had been ''absolutely surprised" when a colleague complained that he had plagiarized. ''I said, 'Oh, my God,' and I looked, and I said, 'You're right, I don't know how it happened.' "
So he wrote the letter to Science dropping the dime on himself, he said, but the response from colleagues, including those he had considered friends, was so nasty that he left the profession for seven years, working instead as an antiques dealer and real-estate developer, before returning to the classroom.
''Academia is a terrible place," he said. He does not know enough about the case of Harvard undergraduate Kaavya Viswanathan to judge it, he said, ''but yes, I'm very sympathetic."
Carey Goldberg can be reached at email@example.com