"Thorough research" means at least three things:This is a very good and very concise answer, but I have found that this answer is also terminally discouraging to many researchers. When I am teaching a class on research of any kind, when I begin to discuss the huge number and diversity of records available, I can sometimes see the shoulders of my students droop as I talk about all the places to search.
- Using all identifiable resources for the area or problem.
- Using original records, not just published derivatives. Indexes, databases, abstracts, and authored narratives can be wonderful resources. If and when they are, they should also point us to originals, for fuller information or correction of published errors.
- Not stopping with the first record that gives an "answer." That answer may be wrong. If we don't search for additional records on the same issue, we won't discover the error—which means all work we do on the foundation of that wrong information may be a total waste of time, money, and brainpower.
This answer may seem obvious to someone who has spent years researching records, but for newly minted researchers, it can be devastating. They ask questions such as why on earth would you keep looking for records when you already found the information you were looking for? Isn't it enough to find my family in the U.S. Census? What more do I need to establish their identity? And then there is the final note, who cares about a ton of references for the same fact?
I am afraid that I have not had very persuasive answers to any of those questions. The answers all seem to fall into the category of listening to the safety talks given at the beginning of any trip in a commercial airliner. You know that safety equipment is not really going to help you all that much if the plane crashes and the safety talk is just a reminder that some crazy person might decide to shoot your plane out of the sky at anytime, but you still go ahead with the trip anyway.
In other words, admonitions that you need to keep searching for the same information after finding what you expected seem overly cautious. It takes some considerable amount of experience before you begin to realize that all records have a possibility of being wrong. I am always amused when someone comes to me with a complaint that the U.S. Census record they just found for their family is wrong. For some, this is an inexplicable mystery, for others, it is a wake up call. Some researchers finally begin to understand that the records can be entirely wrong and in some cases intentionally fabricated.
I am researching a case right now where the ancestor's birth date is different in three different records. The problem is that determining the date of birth is crucial to identifying the individual because of a very common name. What if I had stopped at the first record with the first date? I wouldn't even know there was a problem.
The title to this post is obviously taken from the wording of the Genealogical Proof Standard proposed by the Board for Certification of Genealogists. The very first standard is a "reasonably exhaustive search." This is also the intention of the reference to a "thorough research" in the blog post cited above. Both ideas are open ended. This reflects the reality of genealogical research that no fact is finally determined. Every fact is questionable and can be changed at any time with the discovery of further documentation.
This is the Great Divide among genealogists: between those who recognize the tentative nature of all of their findings and those who accept the first record they find as the gospel truth. It is the difference between building with bricks or toothpicks. I have actually been criticized for adding too many supporting documents. Some people act as if my list of references is excessive. You might note the suggestion made in the first numbered rule listed above: "Using all identifiable resources for the area or problem." Yep, that means all and that means my lists of references are never entirely complete no matter how long they might seem to be.
I would guess that the vast majority of genealogists never realize the scope of what it means to do a reasonably exhaustive search, but without that principle as a foundation, all unsourced pedigrees are tottering on verge of collapse.