Primary source

In the study of history as an academic discipline, a primary source (also called original source or evidence) is an artifact, a document, diary, manuscript, autobiography, a recording, or other source of information that was created at the time under study. It serves as an original source of information about the topic. Similar definitions can be used in library science, and other areas of scholarship, although different fields have somewhat different definitions. In journalism, a primary source can be a person with direct knowledge of a situation, or a document written by such a person.

Primary sources are distinguished from secondary sources, which cite, comment on, or build upon primary sources. Generally, accounts written after the fact with the benefit (and possible distortions) of hindsight are secondary. A secondary source may also be a primary source depending on how it is used. For example, a memoir would be considered a primary source in research concerning its author or about his or her friends characterized within it, but the same memoir would be a secondary source if it were used to examine the culture in which its author lived. "Primary" and "secondary" should be understood as relative terms, with sources categorized according to specific historical contexts and what is being studied.

In scholarly writing, an important objective of classifying sources is to determine their independence and reliability. In contexts such as historical writing, it is almost always advisable to use primary sources and that "if none are available, it is only with great caution that [the author] may proceed to make use of secondary sources." Sreedharan believes that primary sources have the most direct connection to the past and that they "speak for themselves" in ways that cannot be captured through the filter of secondary sources.

In scholarly writing, the objective of classifying sources is to determine the independence and reliability of sources. Though the terms primary source and secondary source originated in historiography as a way to trace the history of historical ideas, they have been applied to many other fields. For example, these ideas may be used to trace the history of scientific theories, literary elements and other information that is passed from one author to another.

In scientific literature, a primary source is the original publication of a scientist's new data, results and theories. In political history, primary sources are documents such as official reports, speeches, pamphlets, posters, or letters by participants, official election returns and eyewitness accounts. In the history of ideas or intellectual history, the main primary sources are books, essays and letters written by intellectuals; these intellectuals may include historians, whose books and essays are therefore considered primary sources for the intellectual historian, though they are secondary sources in their own topical fields. In religious history, the primary sources are religious texts and descriptions of religious ceremonies and rituals.

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