This isn’t entirely true - they’ll probably write down things that they think are worth writing down, but not things that they think are so obvious no one would need to look them up. For example, Romans writing about concrete talked about mixing it with water, but never felt the need to specify that you mix seawater, because that was too obvious. It wasn’t until fairly recently that anyone figured this out. Meanwhile the Egyptians wrote about the land of Punt but never specified exactly where it is, and historians still aren’t sure exactly where ‘Punt’ was. Medieval recipes (and a lot of older recipes) often omitted measurements, and lacked standardized measurements since standards hadn’t come about. Modern cookbooks don’t typically specify that the ‘egg’ we use is a chicken egg, or that ‘cooking oil’ is vegetable oil.
So even in a literate society, there’s some information that’s not actually captured in the written materials. If you come along later and try to interpret the written materials with the language but not the background learning and culture that they would expect, you’re going to find gaps, and in some cases really significant gaps - like not knowing that you should use seawater for Roman concrete, or not knowing to use chicken eggs for a recipe from the 20th century.
Thank you for the tag and mention, @Ruken and @GreenWyvern. Knowledge systems of oral cultures is my field of research - and the topic of my PhD and four subsequent books. I can only skim the topic in this response.
I don’t think anyone would claim that oral cultures can store the same amount of information as literate cultures. As to the actual amount, that is hard to quantify as people have explained above. My research is specifically on the methods by which such vast amounts can be stored in memory. They store valuable knowledge in very robust formats, and ensure that it is maintained accurately through strict rules and processes. They store a pretty vast encyclopaedia, and use the most wonderful techniques to do so accurately.
The 1625 plants (not plants and animals) of the Hanunóo in the Philippines has been mentioned. It is important to explain that this cannot be done using general memory.
You have memorised all the common plants, animals and so on - the easy ones. Hence only in the 30s. That is what is known as natural memory. But there are will be many hundreds of species of insects and a thousand more of plants that are in your environment that you have never noticed, let alone know a name and properties for. That requires memory training, and no - it isn’t easy. I suggest that you try just the birds of your area. They probably number in the hundreds of species. The first 30 will be easy. From then on, you get to birds you might not see for years, and many that you will have never seen before, and many that are very similar little brown birds. That exercise will soon teach you that it is not easy. Birds are the easiest genre which is why they are so widely identified as a hobby. Plants are way harder. And insects are horribly difficult.
One study of the Navajo had knowledge keepers naming and classifying 701 invertebrates from memory, along with habitat etc. Only 10 were botherers (knats, fleas ), one eaten and the rest known for knowledge sake. And used in mythology as a metaphor for ethics and other abstract concepts. Mythology is a mnemonic device because a story alive with characters is far more memorable than straight facts. That is a really important theme of my work. The story encodes the valuable information.
Add to the plants and animals: astronomy, trade agreements, ethics, laws, technologies, geology, medicine and treatments, history, really complex genealogies of everyone known, weather conditions and indicators, timekeeping … the list goes on and on. And then hundreds of kilometres of navigation - land and sea.
The Australian Yanyuwa have worked with researchers to map over 800 km of ‘songlines’ - sung pathways through the landscape - all stored in memory and taught. Those pathways become memory palaces, with information stored at huge numbers of locations on the way - that way the landscape becomes Country. My research showed that this method of using the landscape as a memory palace (the method of loci) was used by all oral cultures globally for which I could find the information.
We have robust evidence from Australia of knowledge of landscape changes going back 17,000 years - and that research will probably go back further into the 65,000 years or so of continuous (but not unchanging) culture. Tellingly, stories storing the information about the creation of crater lakes, for example, do not exist for lakes which predate Aboriginal presence on the continent. Citation: Patrick Nunn, The Edge of Memory. I can give cites for everything I claim - just ask and it shall be yours! There are 800 references listed on my website.
As a time comparison, I looked at archaeological sites which showed the evidence of a set of ten criteria I used to detect if the monuments were primarily knowledge sites. Stonehenge, for example, is a mere 5,000 years old. That is all documented in my Cambridge University Press academic book Knowledge and Power in Prehistoric Societies - ridiculously expensive but thoroughly peer reviewed. My trade books are far more readable.
So, no - oral cultures can’t store the vast libraries available to a literate culture. And most of that isn’t really worth saving - loved the cat photos reference above! But oral cultures use memory methods way beyond anything used in literate cultures - complex versions of techniques used by contemporary memory champions - and which match the recent discoveries about neuroscience and brain plasticity on memory. The ways in which they do that is extraordinary - and we have a great deal we can learn from them.
We can have both literacy and orality! We can have it all! Hence my current work is in the application of these mnemonic technologies in contemporary life, especially in education.
That was once a problem, and some information was in fact lost that way. But it’s a really easy problem to solve, once it’s recognized, and it’s now recognized. Digital information is only lost when the readers are scrapped, if it hasn’t already been copied over to some other, more modern, digital medium. And such copying is easy, and new digital media have so much greater capacity than old media that there’s no reason not to do so as a matter of course.
I suspect this is part of why Religion was such a fine purveyor of knowledge in pre-literate societies. You don’t need a hymn or ceremony written down to get the information right.
Human memmory is prodigious. Along with Homeric stories, there are also cases of people being able to recite the entire Koran by heart. I think too, a lot of memory is sequential - cue a line, and many people could recite the rest of the song or poem or joke. (My wife complains when I do this, when a certain word or phrase triggers recitation of an entire Monty python skit.) It’s just an attribute that atrophies typically when something can be written down, just as remembering appointments atrophies when your smartphone tells you your schedule. I have several thousand songs on iTunes and I probably recognize two thirds of them within the first opening notes.
What happens if someone dies? This is the beauty of reciting things as rote or song or story - the elders tell it to the not elders, and so they become elders and also remember it and pass it on. In the days before radio and TV and the internet, things to do at night involved listening to stories, or village dances, or expanding the tribe. Listen to the same stories night after night, and someone will remember them for next year. Wander the forest with grandpa, and he will tell you about each plant you see and what it’s good for.
Anyone who grew up in the era of 3 networks and reruns knows how repetition can make you very familiar with a story.
But again, I feel this is not appreciating the size of the body of the knowledge that lies outside of human memory. Yes, people memorize the Koran. But people don’t memorize Wikipedia.
This is a major point. People sometimes envision a single storyteller/knowledge-keeper passing down knowledge to others a single person at a time. This was not the norm. At least, not in non-literate tribal cultures.
Instead, many different storytellers would retell the collective knowledge over and over to a large group. If a storyteller got something wrong the elders in the group would correct him/her in front of everyone. New storytellers/knowledge-keepers were taught and encouraged to teach others long before the elders who taught them passed away.
It may not have been a huge amount of knowledge in modern terms but most non-literate societies did have error-correcting mechanisms and redundancies like this in place to protect the knowledge they thought was important.
This is fascinating! If you don’t mind a bit of a tangential followup question - something I have heard of but always dismissed as farfetched is the idea that some indigenous cultures have preserved through oral traditions memories of species that have been extinct for thousands of years in that region. Your crater lake example makes me wonder if this is something that’s actually possible?
Knowledge of long extinct animals, and species which only live great distances away, are well known in Indigenous cultures. The oral traditions are probably not the sole method because these animals are often recorded in rock art which serve as a mnemonic device for the stories.
Stories of animals are probably less robust than those of the landscape because of the fundamental role of the landscape in the memory system. But they are certainly known for long time spans.
This is true. But then, the collective written wisdom is the wisdom of 7 billion people (minus a substantial number of morons), plus several billion past members. There’s also a far more complex society and related information. A primitive society in Greece probably had no travelogue of China or Australia, nor could it list the periodic table and the molarity of each element. OTOH, if you polled the 7 billion people wandering the earth on some question that had relevance to somebody’s life, probably at least one could tell you the answer without looking it up. yes, there’s things like tables of square roots to 10 decimals that we probably don’t know or care about - but the things embedded in our memories are often relevant life skills.
Could the ancient Greeks give you an oral travelogue of Britain? There’s a suggestion that the trade routes with Europe involved travel up the rivers off the Black Sea and then to Scandinavia. The Odyssey mentions being shipwrecked in a land with frost where the sun stayed up almost 24 hours. If someone actually made the journey to northern Europe, the stories he came abck with would enter the folklore while they were relevant and important.
Who knows how much data was accumulated and now lost.