Proof is not a document. It’s a body of evidence. As biographers or historians of whatever ilk, we do not ‘prove’ a point by discovering a record that asserts something. That assertion could be wrong. If so, any further work we do on the basis of that misinformation will likely be wrong or irrelevant.
Not even a stack of documents or a list of sources can constitute proof, unless we explain their significance individually and collectively. The piece of writing in which we do this is called a proof argument.
A convincing proof argument will present the evidence from each document. It will frankly discuss the strengths and the weaknesses of each source and the information it provides. It will discuss the contradictions we found and how we resolved them. It will explain how and why, for the issue we are trying to prove, the whole body of evidence points to only one reasonable conclusion.
Achieving proof is a process in which we assemble evidence, test it, refine it, and reinforce it until that body of evidence is solid enough to withstand contradictions and counterclaims. As with any construction project, results are only as good as the materials and the labor we invest.
Need a model to see just how this works? EE's QuickLessons, accessible under the "Home" tab or in the "QuickLesson Archive," provide several of them using a variety of thorny problems
Photo credit: "Two Men Accused Against Himself," CanStockPhoto (http://www.canstockphoto.com/images-photos/argument.html#file_view.php?id=14925683 : downloaded 4 August 2014), used under license.