Alligators and Academia: The Importance of Primary and Secondary Sources

by Chelsea Lee

Have you heard about how alligators infest the New York City sewer system? The ones brought north by Florida snowbirds for the summer as pets, who were then jettisoned after they outgrew the family bathtub? Indeed, your cousin’s best friend once saw one with her own eyes. Or, at least, that’s what your cousin told you. But you wonder, is it really true, or is it just an urban legend?

Reliable Sources in Academic Research Are Usually Primary Sources

Likewise, when it comes to academic research, it’s extremely important to make sure that the claims you make are backed up by sound evidence, or else your paper won’t stand up to scrutiny from your professors or colleagues (just like that alligator story didn’t hold up once you started looking into it).

As we saw with the alligator story, one of the best ways to help ensure a source’s reliability is to make sure you’re reading a firsthand account, or a primary source, from someone who saw the events for him- or herself (like the best friend), rather than a secondhand account, or a secondary source, from someone who only heard about the events but didn’t witness them personally (like your cousin). Most of the sources you use in a research paper or thesis should be primary sources, not secondary sources.

How to Spot a Primary Source in the Wild

Primary sources can come in many different forms. For example, a journal or magazine article might report the results of an original experiment, or a book or website might describe a theory or technique the author has developed or has expertise in. Note, however, that not every article, book, website, and so forth contains primary research. To determine whether a document is a primary source, ask, did the authors discover this finding themselves (primary source), or are they reporting what someone else found (secondary source)? 

You’ll have to evaluate each source on a case-by-case basis, but some document types tend to make promising primary sources:

• journal articles;
• books and book chapters;
• some magazine and newspaper articles;
• reports, such as from government agencies or institutions;
• dissertations and theses;
• interview and speech transcripts and recordings;
• video and audio recordings;
• personal communications; and
• webpages.

Secondary Sources: Second Best?

In our alligator story example, the word of the secondary source, your cousin, ended up not being too trustworthy, and that’s why we shied away from citing it. But that’s not always the case with secondary sources—in fact, many secondary sources can be not only reliable but also extremely helpful during the research process. For example, a textbook or an encyclopedia (including Wikipedia) can help you get acquainted with a research area by summarizing others’ research. Or you might read a summary of one scientist’s interesting study in someone else’s journal article. 

In these cases, however, the chief advantage of the secondary source is not the quotes that you find but that it points you to the primary source through a citation. It’s important to read (and then cite) the primary source if you can, because that will enable you to verify the accuracy and completeness of the information.

It would not look good for you to cite a secondary source (like your cousin with the alligator tale) only for someone else (like your professor—or animal control) to inform you later that the truth was in fact something quite the opposite. Even when secondary sources are highly accurate, being thorough and reading the primary sources helps demonstrate your merit as a scientist and researcher and helps others find that helpful information.

Citations to secondary sources are permissible under certain circumstances. For example, if you are discussing Wikipedia in your paper, you should cite it (here are some more of our thoughts on citing Wikipedia). Likewise, some primary sources are unobtainable (such as if they are out of print or impossible to find) or written in a language you don’t understand, so the secondary source is what you should cite. Or the secondary source might offer an analysis of the primary source that you want to refer the reader to. See our post on how and when to cite secondary sources (a.k.a. a source you found in another source) and refer to Publication Manual section 6.17 (p. 178) for directions and examples of citations to secondary sources.

We hope this discussion of primary and secondary sources has helped you understand what types of sources are most effective and helpful to use in a research paper. Also we hope that you will contact us if you ever do find that alligator, because the family bathtub just isn’t the same without him.