Author John Tosh outlines in his book ‘The Pursuit of History’ two approaches to evaluating a document or source. These are namely an External Criticism and an Internal Criticism (Tosh, 1984. 58)
The Oxford School Dictionary defined a criticism as the expression of disapproval of something on the basis of perceived faults or mistakes. (Oxfords School Dictionary, 2003. 109) By applying this these criticisms to any historical source or potential source a historian can identify whether or not the source is worthy of use.
An external criticism is one that firstly tests a sources authenticity, it questions the origins, date, author and other key factors against what is already known and proven of the time in question. This process can identify any discrepancies or forgeries, yet the source should not be discarded. Some of the most famous sources in history have questionable authenticity such as the Bixby Letter whose author is widely debated (Abraham Lincolns Most Notorious Forgers, n.d*). By establishing a sources’ credibility the historian can determine the weight it holds or the reasoning behind such falsified documentation, then seek to question the motives of the forger. (Tosh, 1984. 62) This method in itself holds some problems, as a document could be externally sound but the content can be tainted.
Thus an Internal criticism must be applied. This is analysis of the content itself. A historian must account for a larger variety of factors that led to the creation of the document. Whether the author was a first hand witness, the mind-state of the author, take into account prejudices, bias, suppression, political influences, intentions and self-interests. This approach deals directly with the subject matter and delves into its complexity. (Kent, 1941. 67) An example is the Han Emperors of China from 206 BC who took interest in history and thus developed a branch of