The word "proof" confuses some genealogists and scares others. The confusion centers on the fact that different disciplines and occupations define "proof" differently for their own uses. Researchers coming from different pre-genealogy backgrounds may assume that everyone defines and uses proof in the way in which they are familiar. The fear comes from negative experiences with creating an "argument" for a composition class, constructing geometric proofs in a high school geometry course, or being on the "negative end" of "proof" in some legal sense.
Nothing to Fear
There's no reason to fear genealogical proof. There's no genealogy police sitting behind the leaves on the genealogy tree waiting for you to speed past. You won't be arrested for incomplete citations. An understanding of proof can assist any genealogist into better research and better conclusions--and we all want that.
What is Proof?
Genealogists, generally speaking, define "proof" as that written argument supporting a specific conclusion. Proofs written for a scholarly journal better not contain comma splices--whatever they are. Proof written for your own immediate use can contain comma splices and other grammar mistakes (although spelling errors make you look careless and that will impact how others judge your work). Proof written for a genealogical journal needs to make sense. Proof written for your own use needs to make sense. A genealogical proof argument is a clearly written and carefully constructed analysis of information (evidence). That's the part where it has to actually make sense. Evidence used has been obtained as a part of comprehensive research. That is, you've not overlooked obvious sources of information that could answer your question, you've even looked in some unexpected places for information, and you have also discussed information that is inconsistent with your conclusion and explained why you think that "other information" is incorrect. You cannot just pick one document that it consistent with your point and say that's "proof." It is not. Part of creating a proof is discussing all the evidence you have found.
Is it difficult? No. Do some people make it sound harder than it is? Yes. Personally speaking, genealogical "proof" is "easier" in post-1850 families. Before then, records and sources are not always as clear cut.
A genealogical conclusion, supported by genealogical proof, can always be revised if new information comes to light.
My job defined "proof" differentlyMine sure does. In mathematics, once there is a proof that is based on a set of assumptions and sound reasoning, the result is proven. Period. There may be additional ways to prove the result, but the result itself does not change. Mathematicians don't look for "evidence" in the ways that other sciences do. When I use the word "proof" in a genealogical sense, I have to constantly remind myself that I am not using it in the mathematical sense. And I have to remember, that if I want to play with other genealogists, I need to be using the proof concept in the same way that they use the proof concept.
But my definition of proof is better.
No it is not. It is different and it may work for you and your discipline. Within your own personal work, you can define proof differently. That is up to you. But if you want to "play genealogy at a certain level," you will have to follow the general concept of "genealogical proof." And it really isn't that hard. Genealogy proof, in a nutshell, can be revised if new evidence is located, and is the result of looking at all appropriate sources, extracting relevant pieces of information and creating a well-written, clearly reasoned conclusion. That concept isn't hard. What's hard is doing that in a 1690 era Virginia family that left few records. There the difficulty is not the proof itself--but the time period and the location. And that's often the difficulty--constructing a "good" proof requires a knowledge of the time period, the location, and the relevant records--and that's not something a researcher can develop overnight.
Some people do make genealogical proof too difficult. Others argue with the definition itself. I wrote genealogical "proof" long before I became familiar with the academic concept. Other did as well. That's because sound research, soundly analyzed, and soundly reasoned is the goal--no matter what you call it.