What is a Primary Source?

This descriptions comes from Michael Engle's guide entitled Primary, Secondary, and Tertiary Sources: A Quick Guide.


Each academic discipline creates and uses primary and secondary sources differently. The definition of a primary source only makes sense in the context of a specific discipline or field of inquiry.

  • In the humanities and the arts, a primary document might be an original creative work.
  • It might be a part of the historical record written about, or in proximity to, an event.
  • In the social sciences, it might be survey data.
  • In the sciences, it might be a publication of original research.


Here are two definitions that try to capture the elusive nature of primary documents.

A definition from Cornell University: "Primary sources are the main text or work that you are discussing (e.g. a sonnet by William Shakespeare; an opera by Mozart);
actual data or research results (e.g. a scientific article presenting original findings; statistics);
or historical documents (e.g. letters, pamphlets, political tracts, manifestoes)."
["What is a Source?" Recognizing and Avoiding Plagiarism. Cornell University. College of Arts and Sciences.]

A definition from Yale University: "Primary sources provide firsthand testimony or direct evidence concerning a topic or question under investigation."

"They are usually created by witnesses or recorders who experienced the events or conditions being documented. Often these sources are created at the time when the events or conditions are occurring, but primary sources can also include autobiographies, memoirs, and oral histories recorded later."
[Primary Sources at Yale]

Primary Source Collection Guides

Searching for Primary Sources

There are so many types of primary resources to, and their nature varies so much, that it is impossible to list all of the resources where you might find them.  Government documents may be searched in one place, while images may be searched in another, and data may be searched in yet another.  For topics in the Humanities and Social Sciences, one possible approach that you can take to get started is to search the library catalog and include various types of primary sources in the search. 

For example, in Cornell's catalog, you can select the advanced search feature.  In the top line you can enter the topic that you are hoping to research.  In the second line, enter primary source types, for example; Diary memoir interview correspondence speech letter autobiography.  Select "Any" from the dropdown to tell the catalog that any of those words may appear.  While this search will not get all of the primary sources on that topic, and while their may be some secondary sources that will appear, it is one of the more efficient ways of having a look and seeing what primary sources are available.  This technique does not work particularly well for data.

Another option in the catalog could be to select formats that are often primary in nature.  For example, you can run a search, then select "Manuscript/Archive" or "Musical Recording" or "Map" and you can limit the results to those categories of materials.  Again, this strategy is not perfect, but it can help.

Another effective options is to go to primary source collections.  Have a look at some of the resources on the right for example of primary source collections.