Using Occam’s Razor in Genealogy

Occam’s Razor is a philosphical tool that helps you zoom in on the most likely explanation. A lot has been written about Occam’s Razor, but it boils down to “the simpler explanation is usually correct.”

We can use this in genealogy in different ways:

• We can use Occam’s Razor to determine the most likely hypothesis. If we find a combination of unusual circumstances, Occam’s Razor tells us that a single cause that explains all events is more likely to be correct. This can allow us to target our research plan to research that hypothesis first.
• We can use Occam’s Razor to alert us to potential conflicts. If we have a combination of unusual events without a common cause, we should check our assumptions to make sure there is not a simpler explanation.

Man shaving, 1933. Credits: Willem van de Poll, collection Nationaal Archief (CC-0)

Example: Triplets in 1702

I have an example from my own tree. My one-place-study of Winterswijk, the Netherlands, includes over 50,000 people from the area between say 1600 and 1900. That entire database only had one set of triplets, born in 1702. One of the triplets was named Gemma, the only person by that name in my database. In Winterswijk, people traditionally named their children after family members. I did not find any original names until the 1960s. So we had two unusual circumstances: the only triplets in three centuries, and the only unique name in three centuries. Applying Occam’s Razor means I should try to rule out a simpler explanation before accepting this unusual combination as fact.

By looking at the original, I found out that the transcription I used originally had an error. They were not triplets, but “Gemina” (twins); misread as “Gemma” . The two girls had ordinary Winterswijk names, Aeltjen and Stijntjen. The transcription error caused both unusual circumstances: the only triplets and the only person with an original name. Occam’s Razor saved the day.

The example also teaches another principle: that we should always used the best quality evidence available. Using the original record instead of the transcription resolved the issue.

Baptismal record of Aeltjen and Stijntjen Mengers, twins