When you hear the term half-life you might be drawn into thinking about decomposing atoms, but in the field of history the term also carries great relevance.
Specifically, the term ‘half-life of knowledge’ is very important when applied to the way we understand the past. Essentially the half-life of knowledge is the amount of time that has to elapse before half of the knowledge in a particular area is superseded or shown to be untrue. Just because it happened in the past doesn’t mean our understanding of it will remain unchanged.
Of course there are some things (particularly in modern history) that we will remain almost completely certain of – these are the fundamental facts; dates, names, times, places. It is hard to imagine that someone will turn around and prove that the atomic bomb dropped on Hiroshima during World War Two did not happen on 6 August 1945. In the time of recorded history, some things are as close to absolute as is, by all accounts, possible.
However, when we begin to interpret or theorise about historical events, it is understandable that over time many historical truths will become falsified. After all, people once thought the world was flat, that light was emitted by the human eye, that hundreds of witches were burnt at the stake in Salem (only 20 died, none by fire), and that Lady Godiva rode naked through the streets of Coventry.
These accepted truths over time were found to be nothing more than widely believed, inaccurate rumours that had been passed down through history. Needless to say, when we start trying to analyse why things happened, there is huge scope for disparity between theories and reality. A well-respected historian’s opinion might easily be taken as gospel at the time but as new information becomes available and approaches to history change, so too does the way we understand events.
What is accepted today might be outdated or disproved in a decade from now. Call us biased, but that is why internet-based resources can be so valuable. Undoubtedly there are inaccurate pages online that can lead a burgeoning historian astray, but so too are there books in libraries containing archaic interpretations of past events. As such, trusted web-based sources now represent a great tool in the constantly evolving academic field of history.