Brief Guide to Plagiarism

Plagiarus means kidnapper in Latin. Plagiarii were pirates who stole children.

By analogy, plagiarizing is like stealing the brain children of someone else. You cheat the author of the idea out of recognition, and you lie by representing it as your own. When you plagiarize, you commit a serious ethical violation. Misusing the work of another author, even when you do not plagiarize directly by presenting another author’s exact words as your own, is also a serious ethical violation.

Because these violations have consequences ranging from a failing grade to expulsion from school, it is in your interest to understand the many forms that plagiarism can take. Plagiarism sometimes happens because students are sincerely confused about what constitutes intellectual property, what exactly is a “source,” and what sources need to be cited.

Here are some basic rules to follow.

  • Common ideas—that students may be inclined to use AI to cheat, for example—don’t need to be cited, but specific studies of student cheating do. For example: Mark Massaro, “AI cheating is hopelessly, irreparably corrupting US higher education,” The Hill, August 23, 2023.
  • Cite sources for distinctive perspectives and opinions.
  • Cite sources for specific evidence you use to support your arguments: narratives, statistical data, biographical information, documents, etc.
  • Verbatim phrases or passages must always be placed in quotation marks and cited correctly. If you paraphrase an author’s ideas, you must do it in your own words. If you are paraphrasing so closely that the phrase might as well be a direct quote, don’t take a chance. Make it a direct quote. Quite a few well-known historians have used phrases, sentences, and paragraphs from other scholars’ books that were so close to the original, they might as well have been lifted word for word. They committed plagiarism.
  • Never leave your reader in doubt as to when you are speaking and when you are using materials from a source.

Citation Methods

  • The most important thing is to use one citation system consistently and correctly.
  • Sequentially numbered notes that appear either at the bottom of each page (footnotes) or at the end of the document (endnotes) is the system that historians prefer. That is because we tend to use lots of citations.
  • In-text references with bibliography is more common in the social sciences. It is acceptable, but a substantial number of parenthetical citations can make reading the text somewhat more difficult.

For examples of common citations, see the Citation Guide.