Sources. Everyone knows if you’re going to write a paper or book, you need sources. Lots of them. Even in fandom and other places, we talk about “source material”. There are categories of sources, hopefully something everyone remembers from high school. You can have a primary source, secondary source, and tertiary source. Then you can talk about literary or archaeological sources. In a drunken slur you might even hear about BBQ sources or Teriyaki source. Lots of source, but not all sources are equal. So grab a beer and have fun reading about the different sources used by historians. Hey, you never know, maybe one day you’ll want to find out how bad those politicians and media pundits are lying to you when they talk about their sources.
The first big division is separating out sources in terms of primary, secondary, and tertiary. Loosely defined, a primary source is a first-hand account or artifact. Caesar’s commentaries are a primary source, because he was actually there. Herodotus, on the other hand, wrote about events several decades earlier and was not himself a witness or participant. His work is a secondary source. A tertiary source is basically modern scholarship; works written about other works written about events. Generally, you can rank them accordingly—primary being the best. A word of caution on just accepting any primary source: Even eyewitnesses can be horrendously unreliable.
Another big division is over the medium. For ancient stuff, this pretty much means separating literature from artifacts and archaeology. Sorry, no cell phone videos or DNA. It can get a little weird with things like epigraphy—works written on stone, since the stone itself is an artifact separate from the writing. Now, unlike the ranking above, you can’t really rank literature over archaeology or vice versa. The reason is they end up being two sides of the same story, each with their own merits and detriments. Authors can lie, but so can artifacts. Finding a sword in the grave of a male, for example, does not mean the guy was a warrior. Objects can also be forged and misinterpreted, like the Mask of Agamemnon or Donald Trump’s hair—I’m pretty sure that thing is a separate species.
There is a fine difference between “sources” and “manuscripts”. A lot of the manuscripts we have are from the Middle Ages, even if the work itself is from much earlier. This can cause problems, since these are the days before the printing press, all manuscripts were copied by hand. As a result, the opening to Caesar’s Gallic War, “all Gaul is divided into three parts”, ends up as “all that large area we call Gaul in the North we divided into three parts fuzzy purple dishwasher”. This is called interpolation, where notes written in the margin end up accidentally in the body text itself. You might also have a saut du même au même, which is a fancy French phrase meaning the copyist fucked up by accidentally skipping over a word or line, creating a gap or “lacuna” (yes, we really use all these stupid terms). The printing press basically eliminated this issue, which is why high school textbooks aren’t reprinted as if the dicks are supposed to be there. Scholars spend a good amount of time trying to reconstruct the texts back to the original. If you read an Oxford Classical Text, a study Bible, or a critical edition of Shakespeare, you probably notice at the bottom a bunch of letters and things next to the passage number. This is the “apparatus criticus”—as we like to say in Latin because we’re pretentious nerds like that. This is useful because it lists all the manuscript differences and which manuscripts have which variant. It also lets you know when an editor has emended the text for something like a spelling mistake. Each manuscript is a “source” in itself, which is why the slight distinction can be important.
We usually are scrambling for manuscripts in any case so variants don’t tend to be a huge deal. For some things though, suggestions of interpolation have pretty big consequences, like a really bad autocorrect saying you like “homicide” instead of “hummus”. One such suggestion is that Book 24 of the Odyssey is one big interpolation. Not a prominent view among historians, but the removal of an entire book has some serious impact on interpretation.
If you’re looking for manuscript issues though, none shine any light next to Bible manuscripts. The sheer scale is sometimes daunting; there are over 20,000 New Testament manuscripts, written in a half dozen languages or so. There’s an estimated 100,000-400,000 variations between these manuscripts. Scholars have already come up with a ranking system. 5 categories with category 1 being generally the oldest and best. It’s a pretty small category though, with the majority in the less useful 3-5 categories. This complicates the idea of source criticism, basically the process of making sure we don’t accidentally cite the Onion, since each passage in the Bible can have dozens of variations, and cause additional problems for determining things like historical accuracy.
This whole source reliability and classification thing is actually pretty old though, and the ancients themselves thought about the material they used for writing history. Great example cases are the difference between Herodotus, the father of history, and Thucydides, the father of scientific history. So let’s look at the sources our sources used for source material, like source Inception—Sourception! Herodotus tells us he asked “learned men” and other people about the Persian Wars. Occasionally he will give multiple explanations and pick one he thinks is accurate, but in other cases he doesn’t seem to take great care in separating rumor from fact—he would have made an excellent journalist today. Hence all the goofy supernatural stuff he sometimes throws in, and his other nickname as the “father of lies”. Thucydides, by comparison, left out the goofy or unreliable information, and checked his sources for accuracy—he would have made a good contributor to Snopes.
The issue of source material can be crucial for determining the historical accuracy of events for even the most iconic figures in history. Alexander the Great had official historians in his entourage. That means we should have multiple accounts written by first hand eyewitnesses, pretty much the cream of the crop for source material. Yay! Except all these primary sources are lost. Boo! We have zero primary written accounts for Alexander the Great—I know, even I didn’t believe this at first, but feel free to look it up, because it’s true. We have guys like Arrian, writing about Alexander a mere 500 years after his death. One of Arrian’s sources was the lost work of Ptolemy, which gives us both some glimpse into the lost history, and some justification for giving a few credibility points to Arrian. So sometimes the lack of primary sources is not too terrible a thing, and with sound enough secondary source material, we can create good narratives—and shitty movies—about Alexander the Great. This explains why historians don’t just throw up their hands and say “fuck it”.
Even in our world of camera phones, live reports, and video evidence, knowing how to tell between sources is probably a good thing. Between Onion articles, conspiracy theories, the overall quality of the internet, and journalistic integrity—or the lack thereof—the ability to critically examine sources is as useful for historians as anyone else in today’s world. We live in the information age, but a lot of that information is complete bullshit, and cats doing funny things. As Abraham Lincoln once said, “Don’t trust anything said on the internet”. And who are you to argue with a man who hunted vampires?
There are a few open source papers on Book 24 of the Odyssey.
Other sites also list the types of sources used in historical research, with varying definitions. I particularly like the OUP’s definition of historians as “Time Detectives”, since it sounds like a bad (good?) Dr. Who spinoff.