One of the 16th century reliefs still existing at the monastery of "San Vivaldo," in Tuscany. It is an early example of a purely image-based communication: an attempt to tell complex concepts, the stories of the gospels, to people who couldn't read. It was a failure, but also a remarkably innovative approach. The time for image-based communication may return with the rapid loss of literacy affecting our times. The problem with this evolution is huge in science, with fewer and fewer people able to read the scientific literature. We are now depending on professional interpreters to tell us what "Science" is, just like long ago illiterate Christians were forced to rely on professional interpreters ("priests") to tell them what the scriptures said. The result is that Science is becoming whatever these scientific priests say Science is. And this is bad, although perhaps not beyond redemption.
Let me start this post by citing a fascinating article written by "Marty Mac's and Cheese" I don't know who Mr. Marty Mac is, but he clearly has a remarkable cultural vision. He notes how Catholicism and Protestantism evolved along separate lines of thought. Protestantism was born as a literature-based religion: Protestants were "people of the book." Conversely, Catholicism catered more to the illiterate.
You can see the difference in the respective churches: Protestant churches are normally austere, while Catholic churches are highly decorated and full of images. The image below is from Marty Mac's post.
A mind trained with the written word is different from a mind without it. The organization of thought required for reading is very different from that in an oral environment. The differences come entirely from communicative form.The loss of literacy skills has been impressive during the past few decades. I note that from my students. They can repeat what they read, or the notes they took in class. But in terms of understanding a complex matter, well, it is a disaster. I note the same trend with my colleagues. When I was a student, I was impressed by the ability of my teachers to go through complex mathematical calculations with just pencil and paper. Nobody does that anymore: when successful scientists need to make a complex calculation, they pay someone to do it for them.
Oral communication is nearly always discursive. Even when someone gives a monologue, it is to an audience, which reacts (perhaps silently) and participates. But monologues are rare and nearly always have a particular social purpose: relating important cultural narratives, or persuading people or expounding to them from a position of authority (what the ancients called rhetoric). But discourse is more typical of oral communication.
Discourse is by its nature unstructured. When you speak with someone, the other person can disagree, change the subject, extend your thoughts in a new direction, or bring up something new. Discourse is extremely unlikely to follow a set of logical presuppositions and explore them all the way to their end. By its nature it jumps around, assembling different ideas from multiple people in a back-and-forth which may or may not represent a coherent whole.
None of this is bad. It is just the nature of having multiple minds in real-time communication with one another through the medium of linear speech. Valuable knowledge can be imparted and also discovered in this process. A single mind following a single set of logical presuppositions cannot arrive at complete knowledge. But oral communication is by nature unstructured.
Not so the written word. Writing forces communication to be continuous and follow some particular path. There is no interlocutor to correct, derail, or add to the argumentation. If discourse is by nature a hodge-podge, with different thoughts from different minds combining to make a gestalt, writing has the ability to unmask whether the thought itself, expressed in language, has internal coherence. The act of writing forces the writer to pay attention to this. The act of reading brings to the attention of the reader whether what is being said has structure and consistency. Literacy is an avenue to greater coherence and precision of thought.
Literacy changes the way people think, or rather it opens up a new manner of thinking. It doesn’t necessarily supplant the discursive oral communication (elite Ancient Greek society, existing on the bleeding edge of the novel technology of writing, considered both oral and written language, in their proper uses, to be learned forms of culture). However, literate cultures have different qualities from illiterate ones. This kind of research is inevitably controversial, but it appears to be the case that written languages (even when they are spoken) more frequently use conjunctions and have more types of conjunctions. Many languages around the world lack a word for ‘or’, not to speak of ‘however’, ‘nevertheless’, or ‘yet.’ You can get on just fine with no conjunctions, or with a smaller number of conjunctions, or just a single generic conjunction that means ‘mostly and.’ This should not be surprising. If language occurs mostly in a context of unstructured discourse, there is less need for lots of connectives that link one set of thoughts to the next (contrariwise, there is more need for discourse elements acknowledging and addressing the interlocutor!). The increased attention to internal coherence in writing seeps back into the oral language here it is in an unexpected way: a multiplication of conjunctions.
Complex mathematics do not arise in oral cultures. This is not to say oral cultures cannot do math — you can find oral cultures comfortable with surprisingly high multiplication baked into their number systems. However, no purely oral culture has developed algebra or complex geometry. This kind of lengthy, step-by-step algorithmic process is something our brains are not naturally very good at. We seem to require an external aid for structuring, in the form of writing, to jump-start higher mathematics. After people are taught step-by-step mathematical processes, they can become quite adept at doing (some limited amount of) math in their heads. It just seems to be true that to take that first step requires writing the mathematical formulae.
Literacy is not just a communicative tool, although it is that too. Literacy causes a shift in how people think. It enables and enforces certain kinds of structured thought and is a step away from the gestalt, ad hoc compositional thought of discursive or oral communication. We all begin our linguistic lives with only oral1 communication, and only later learn to be literate. Literacy is not a replacement for oral language: it is built on top of it, both historically and in each person’s personal development.