Making Inferences and Consistency

Just a few thoughts on inferences, consistency....not an official "edict," but an outloud commentary more to keep me thinking than anything else. No sources are cited in this post, but that's really not the point in this case.

The latest issue of Casefile Clues just went out and one of the items discussed in it was the approximate date of birth for Sarah/Sally Tinsley, probably a native of Amherst County, Virginia. Births during this time period are often approximate ones as few Virginians left birth records in the late 18th century.

I used several items to approximate the time when Sarah was born:

• 1800 census age range
• 1810 census age range
• 1820 census age range
• 1830 census age range
• 1840 census age range
• 1850 census age
• the letter of consent in her 1798 marriage which implied that she was under the age of 21.

Personally, I think that any census age is secondary information when provided by the person themselves. Sarah's knowledge of her age was based upon what someone told her. I'm not entirely certain how accurate those ages are, but the information she provided is direct evidence for her age (year of birth) as it specifically states that information.

The letter of consent signed by her father in 1798 is slightly different. It provides indirect information on Sarah's age as the letter does not specifically state her age--rather the existence of the letter at that point in time likely stems from the fact that Sarah was under the age of 21. Sarah's father, John Tinsley, would have had first hand knowledge of her age so in that sense his knowledge of the information regarding her age is primary.

The census records and the 1798 marriage consent letter all allow for the approximation of a range of Sarah's year of birth within a two to three year time frame. Of course the analysis hinges upon the fact that census records are reliable. However it must be noted that Sarah's ages in all census enumerations are consistent with each other and with her 1798 letter.

Consistency of the census records proves nothing other than consistency. That is, Sarah believed she was born in a certain year and always answered enumerator's questions from that same perspective.

The fact that the ages she gave in the census is consistent with the age implied by the consent letter is a different sort of consistency. In this case, the age implied by her father in 1798 is consistent with the age Sarah provide in the 1800-1850 census records.

Which simply means that John Tinsley told his daughter she was a certain age and she believed him.

Does this mean the age range for Sarah is wrong? Of course not.

But thinking of how things could be consistent and still be wrong is always a good thought exercise

Unless records on your family are entirely consistent.