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ENG 320: Literature of Enlightenment and Revolution

useful resources

Primary, Secondary, & Tertiary

What are the differences between primary, secondary, and tertiary sources?

  • For research in the Humanities, primary sources are usually original "records" which were created at the time an historical event occurred (an "historical event" is any phenomenon or procedure which has taken place [or is still taking place] in a particular time and place). Such sources are the "raw material," "firsthand information" or "original thinking" relevant to an event. They include relevant records of the event, for example letters, photographs, diaries, or speeches. Eyewitness accounts, contemporaneous journalistic reports, or even memoirs and oral histories which are created well after the actual event can also be considered primary sources.

  • Secondary sources comprise what has already been written on the topic, at different times and from different points of view, by other scholars ('experts' on the topic). "Secondary" sources are thus works written on the topic in question by other researchers, whose work has been based on Primary sources after consultation with the Secondary sources on the topic which had existed at the time. The "Review of the Literature" component of full research papers is precisely this wide-ranging review of what all known secondary sources currently say about a given topic, as the foundation for the "new" information you plan to provide in your research.

  • "Tertiary" sources are general explanations condensed from 'common knowledge' on the topic intended for a broad public audience. Tertiary sources are usually not credited to a particular author. They are intended only to provide a superficial overview of what the topic includes, its basic terminology, and often references for further reading (which would usually be Secondary sources, produced by established 'experts' on the topic). You might use other tertiary sources, such as dictionaries, to get a fuller sense of definitions and meanings of the field's terminology.





descriptions of travel
literary works
newspaper accounts
personal narratives
paintings and photographs


prior books & papers on a topic
literary criticism & interpretation
history & historical criticism
political analyses
reviews of law and legislation
essays on morals and ethics
analyses of social policy
study and teaching material


dictionaries & encyclopedias
guidebooks and manuals
population registers