Signal every quotation, even when you cite its source - Preventing plagiarism - Writing your paper

Student's guide to writing college papers, Fourth edition - Kate L. Turabian 2010

Signal every quotation, even when you cite its source
Preventing plagiarism
Writing your paper

Even if you cite your source, readers must know unambiguously which words are yours and which you quote. You risk a charge of plagiarism if you fail to use quotation marks to signal that you have copied as little as a single line.

It gets complicated, however, when you copy just a few words. Suppose you were writing about this passage from Jared Diamond:

Because technology begets more technology, the importance of an invention's diffusion potentially exceeds the importance of the original invention. Technology's history exemplifies what is termed an autocatalytic process: that is, one that speeds up at a rate that increases with time, because the process catalyzes itself (Diamond, 301).

To write about Diamond's ideas, you would probably use some of his words, such as the importance of an invention. But you wouldn't put that short phrase in quotation marks, because it shows no originality of thought or expression. Two of his phrases, however, are so striking that they do need quotation marks: technology begets more technology and autocatalytic process. For example:

The power of technology goes beyond individual inventions because technology “begets more technology.” It is, as Diamond puts it, an “autocatalytic process” (301).

Once you cite those words, you can use them again without quotation marks or citation:

So as one invention begets another to spark a self-sustaining catalysis, the effect spreads exponentially across all national boundaries.

This is a gray area: words that seem striking to some are commonplace to others. If you use quotation marks around too many common phrases, readers may think you're naive or insecure. But if you fail to use them when readers think you should, they may suspect you of plagiarism. It's better to seem naive than dishonest, especially early in your research career, so use quotation marks freely.