Primary and secondary sources
Evidence for past events created at or near the time of the event is what historians call "primary" evidence. This is the basic raw material of historical research, out of which historians fashion their interpretations of the past. Put another way, a primary source is evidence which came into existence during the actual period of the past which the historian is studying. By contrast, a "secondary" source is an interpretation or reconstruction of events written by an historian long after the period in which the events occurred. For example, a modern textbook is obviously a "secondary" source, whereas a medieval charter is a piece of "primary" evidence.
This is a fundamental distinction, which all students of History must grasp firmly, because it affects the strength and validity of arguments used to interpret or explain the past. If the aim of the professional historian is to increase human knowledge by exploring the unknown in our past, then the bulk of the historian's research must be carried out among unpublished primary sources. Popular history, by contrast, does not seek to increase human knowledge but merely to communicate what is already known to a wider audience.
Historians also make a sharp distinction between "witting" and "unwitting" testimony. Witting testimony is the information which the writer of a piece of primary evidence meant it to convey. For example, a cabinet minute or even the minutes of a committee meeting, are the formal record of what was decided. But such a record may also contain clues about the way individuals voted, or relationships between different members of the cabinet or committee, which everyone knew at the time and so did not bother to record elsewhere. The logical analysis of documents, to deduce more than what they say at face value, is sometimes called "reading between the lines". The records of a government department in the sixteenth century for example, will usually yield unwitting testimony about how it was organised, or how procedures changed across time. An experienced historian can sometimes deduce things from gaps in the record, although this "argument from silence" is a slippery one, for "absence of evidence is not necessarily evidence of absence". Historical research, put simply, involves the rational reconstruction of the way things were in the human past from whatever fragments of evidence may have survived.
Most primary sources remain unpublished, in manuscript form (or typescript, for modern sources), in record offices or archives. Some important sources may have been printed in the past, or in modern editions, but such printed primary sources need to be used with care, because the editor may have cut out what seemed to be less important details in order to save space (and printing costs). The professional historian always prefers to inspect the original manuscript, if at all possible. Asking new questions of old familiar sources can often yield new insights.
Historians are omnivorous when it comes to evidence. Like magpies, they will borrow from any discipline which can contribute useful evidence to help us understand the past a bit better. Archaeology, numismatics, sigillography, palaeography, anthropology, economics, demography; even climatology, dendrochronology and other strictly scientific disciplines have made significant contributions to our understanding of past centuries.
Just to give some idea of the range and diversity of primary sources in historical research, here is a shortened list from Arthur Marwick's Introduction to History (Open University, 1977), p.58, of English sources:
- Records of central government: laws, charters, dispatches; Parliament, Council, Cabinet; tax and fiscal records; local records: parish registers, police files, marrorial courts, electoral registers; records of institutions, societies, political parties, trade unions; private business or legal records, company archives
- Official surveys and reports (from Domesday Book to recent Royal Commissions).
- Chronicles and histories: monastic, civic, institutional.
- Family and personal: private letters, diaries, journals.
- Media records: newspapers, pamphlets, treatises, cartoons, posters, advertisements, films, videos.
- Archaeology: coins, buildings, inscriptions, costumes.
- Literary and artistic works: novels, plays, poetry, painting, sculpture.
- Others: maps, photographs, oral testimony, folk songs, etc.