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  • Gravestones in a cemetery
  • Family tree chart and photos
  • My grandparent's wedding
  • Windswept tree on a hillside
  • World War I Army pals
  • Looking up the word family in a dictionary
  • Photo of gravestones in a cemetery
  • My parents' wedding
  • Old family photographs and heirlooms
  • Young person's hand touching old person's hand
  • Looking at a family photo of a woman

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Quite often, clients will ask me if I can prove that they were descended from William the Conqueror, or what proof I have when I tell them that they were actually the great-grandson of Bill the Bricklayer... Then they'll get a bit upset with me when I try to explain that you can never really prove anything in genealogy. 

I thought it was about time I got round to writing a blog post on the subject of genealogical proof, what that might look like, and whether it could ever even exist.

In fact, in the USA, there is in fact a long established and well accepted definition of the term genealogical proof (see Board for Certification of Genealogists website and this book).

This standard isn't as well known on this side of the Pond, but in my view it should be, as I believe it gives us a useful set of guidelines for checking whether or not our research has been as thorough as possible in tackling a particular genealogical question.

But proof??? Does it give really us a method of establishing whether or not some point of genealogy has been proved or not? I would argue it does not.

In fact, I would argue that to even use the term proof in the context of genealogy is distinctly misleading and unhelpful. My feeling is we need to steer people away from any thought or talk of proof and adopt an approach to genealogy which is much closer to the scientific method. 

In science, nobody talks about things having been "proved" (or at least they shouldn't). Scientists talk instead about hypotheses and theories: Newton's Theory of Universal Gravitation, Einstein's Theory of Relativity, Darwin's Theory of the Evolution of Species by Natural Selection etc. Those have all been around for over a century, are almost universally accepted and we have used them to build the modern world, but none of them has been proved. It is always possible that someone could always do an experiment tomorrow that reveals a gaping hole in one of those theories no one had spotted before. Indeed, Newton's ideas on gravity served us pretty well for a couple of hundred years before Einstein improved on them.

In popular parlance, the word theory is sometimes used in a rather derogatory way. We might say: "Yes, but that's only your theory", to dismiss something we don't agree with. But theories are fundamental to the scientific method.

The way science works is that, in an attempt to shed light on some aspect of the world, a researcher will first put forward a hypothesis, which is a proposed explanation for some phenomenon. That hypothesis is then tested through observation, modified, and improved, and, eventually a full fledged theory is developed. But theories are never proven: one theory holds sway for a while, then gets superseded by a better one, then that by an ever better one etc. Einstein's theory supplanted Newton's Einstein's and will (hopefully) someday be supplanted by a "Theory of Everything" that reconciles Relativity and Quantum Theory.  

You can perhaps think of a theory as a model of the universe that gets refined and gradually becomes a better interpretation and reflection of reality as new information comes to light. We should constantly be testing it by looking for new information and checking how well the theory stands up to scrutiny. If the theory is inconsistent with our new evidence, we need to revise it.

But wait a minute! Isn't that the way good genealogy is done too!?

We start with some corpus of information (e.g. baptisms and marriages recorded in parish registers). From that we build a working family tree (our theory, or model of historical reality). Some things will fit together neatly and convincingly, others less so: often there will be many different ways in which the same set of information could be interpreted, and, based solely on the information available at the time, there might be no way in which to make a firm judgement as to which interpretation is most likely to be correct. So we look for more information to help us decide which is right, and, based on any new details that come to light, we may have to go back and change our working family tree so it is consistent with them.

To me, that's not really any different from a scientist taking a set of experimental results, constructing a theory that attempts to explain those results, then doing other experiments to try to see if the theory stands up.

So, I try (but frequently fail, I fear...) to make my clients understand that what I am giving them is just my best attempt to produce a model of their ancestry, based on the (often imperfect, incomplete and inconsistent) evidence available, and should always be considered subject to revision if further information comes to light.

In my view, therefore, we should never talk about "proof" in the context of genealogy. We should only talk about how well our model of historical reality stands up to scrutiny, which aspects of it are less well tested than others, and what further information might be available to refine it.

But hey! That's just my theory!