The Standards Manual written by the Board for Certification of Genealogists (BCG) talks about assumptions and on pages 27 and 27 classifies them according to the following structure:
- fundamental, valid, and unsound
Fundamental assumptions are generally accepted without additional documentation or evidence and are usually the result of an entity being a human living on the planet. Most of these assumptions are relatively obvious. The mother is present with child at time of birth, people are alive when they sign documents, if it’s 1812 a person can’t be in England and Boston on the same day, etc.). Fundamental assumptions are usually impossible to violate (exceptions would be conceptions and births that involve modern medical science). Valid assumptions are ones that are usually accepted unless there’s solid evidence to the contrary. Apparently they are things that probably happen most of the time, but don’t have to happen. The BCG Standards Manuel suggests that these assumptions include “coherent” life patterns and behaviors that “generally observed” the social standards of the time (2nd edition, page 26). Unsound assumptions are ones that may be true a majority of the time (my phrase), but not nearly often enough to conclude them without supporting evidence (a couple getting married in the same location as where the first child is born is one example).
Fundamental assumptions make perfect sense to me and seem reasonably distinct from the other two. Fundamental assumptions don’t violate the laws of contemporary biological/medical procedures, the laws of physics, or the space/time continuum. Valid and unsound ones appear to not be so clearly separately defined from each other. There’s a nebulous region where the two overlap or something. There may be a range with valid at one end and unsound at the other. I’m also a little hesitant to even assume that everyone always generally observed social standards (which valid assumptions stem from)–certainly most people did follow common conventions, but genealogy isn’t about what most people do. It’s about what one ancestor did. And sometimes assuming a person acted like everyone else is what leads to genealogical confusion in the first place.
And the manual does suggest that valid assumptions are valid unless evidence indicates otherwise.
And that gets to ways that I like to use assumptions–other than classifying them as valid or unsound. Use those assumptions to further your own research.
Think about your assumptions.
- do any violate laws of nature/biology/physics? If so, chuck the assumption unless you have an extremely valid reason for keeping it. Extremely valid.
- remember that anything you assume for which you have no evidence (except for laws of nature, etc.) could be wrong–how would your research change if it were wrong? And if you have no evidence, why are you holding onto the assumption in the first place? The only time a genealogist should use their gut as evidence is when they are taste-testing great-grandma’s old cookie recipes.
- if your assumption is true, are there any records that would have been generated as a result of it being true?
- are you holding onto assumptions for emotional or nostalgic reasons?