Yvette has asked:
One thing I've heard Tom Jones say is that one record is never enough to prove anything, even when using reliable records, since you don't know if it's in the 99% that is correct or the 1% that is incorrect. But what if one record is all you have been able to find?
I am currently researching a family in the Netherlands in the 1500s. Evidence for this time and place is scarce. I've found a feudal register that had consecutive entries for the vassals who were entitled to hold the land. I will use fake data here because the client has not authorized me to share the details:
1515: Pieter Claesse by transfer of Cornelis de Wit.
1541: Leendert Pieters, as heir and son of Pieter Claesse.
1568: Pieter Leenders, as heir and son of Leendert Pieters.
This one source provides direct evidence of three generations of men (the "son of" part is in the actual register). Their patronymics provide indirect evidence to support this: the father's first name match the son's patronymics. The spacing of the different entries is consistent with them being a generation apart. And feudal laws state that estates are inherited by the eldest sons unless it is transferred to a stranger. So even though it's just one record, it consists of different pieces that fit together. You could even argue that this source consists of three different records; the three entries that were recorded at different dates.
I have found some other records that mention Leendert Pieters and Pieter Leenders, but in isolation. I have not been able to find any other records for Pieter Claesse in this area, neither by himself nor with relatives. Just finding this one record is pretty remarkable for this time and place.
In this particular case, I feel that the conclusion that Leendert Pieters is the son of Pieter Claesse could meet the GPS, even though I only have one source (provided I meet the other criteria in the report). I would love to hear your opinion on this.