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This is an umbrella project about sourcing in genealogy.

Please don't add any profiles but feel free to collaborate and contribute.

It's a large topic, so please set up "related" projects to cover more specific areas.

Types of Sources

  • Primary sources, which are the most trusted ones, are written at the time of the event, like the priest write a baptism in a churchbook.
  • Secondary source are less trustworthy than the primary ones, because they usually are written by authors using the primary sources and written later in time than when the events happened. A family history book could fall into this category when the author has included the sources he/she has used when writing the book.
  • Tertiary sources are usually the least reliable sources. They can be written a long time after the events, they can be without sources, they can have used only secondary sources as their own sources, they could be built on theories not facts, and these theories could be poorly substantiated.

Evaluating Sources

Usually we trust sources more the closer they are in time to the events they write about. For example, birth information is more likely to be correct on a birth certificate than on a death certificate.

But at the same time we need to have in mind that the author or the one commissioning the book, may have an agenda for writing what he/she does. We always have to use our critical sense when reading books and try to find other independent writers that have written about the same events so we can get some collaborative information. This is specially important in an online community like Geni, so we don't add wrong information to our genealogies which will spread out like viruses.

Examples of Sources

  • Family tradition is a secondary source or tertiary source because it relies on human memory, not on evidence created at the time of the event. In legal terms, family tradition is hearsay. The more links in the chain, the weaker it is as evidence.
  • LDS Ancestral File is a tertiary source because it is user-submitted information, usually without citation to primary or secondary sources.
  • Vital Records, such as birth, death, marriage records, are primary sources for the events they record, but secondary sources for events in the past.
  • Wikipedia is typically a secondary source because a typical Wikipedia article cites both primary and secondary sources. However, like any secondary source, we need to be careful about accepting the information at face value. It is very common for Wikipedia articles in different language to contain conflicting information about the same person.

Best Practices

  • Cite your sources! Whether the source is primary, secondary or tertiary, citing the source is *always* better than not citing it. A citation allows others to check the source, investigate what the source actually says, recognize known good and known bad sources, and perhaps use it as a guide to find better sources.
  • Use the best source you can find. You might not be able to document every relationship with primary sources, but you can always take time to think about which sources are better or more persuasive. Over time, poorer quality sources (such as unsourced family websites) are likely to be deleted in favor of higher quality sources.