> Chimps literally teach each other to use rocks as tools. Clearly knowledge or 'how to accomplish a task' is something that can be communicated to another.Yes, and no.
Lets take calculus as an example and the skill to take derivatives. If a teacher show you how to take derivatives, you'll kinda get the idea but if you try it, you would face a lot of problems and you probably would need teacher's help.
To become proficient with derivatives, you need to teach yourself by taking a lot of derivatives. But... wait... you are taking derivatives, you're not doing something special that can be called "learning".
Chimps also communicate knowledge by showing the right "ritual" how to accomplish things, students reproduce ritual and somehow learn how to do it properly.
The whole education works mostly in this vein, the method is to make people to do something, and while they are doing it they'll learn how to do it. Magic.
The communication doesn't transfer all the knowledge, and it is pointless to try, because people are different and edge cases are different for different people. For example, I'm always confusing left and right, it was a pain to deal with the driving instructor who would say "turn left at the next crossing" and then I will dutifully turn right. I can deal with it most of the times, I just need to pay more attention to "left" and "right" things. But it is my specific edge case, if I teach others I do not try to communicate the necessity of paying attention for words "left" and "right", and when someone teaches me they do not communicate this to me. There are a lot of such individual edge cases and the more difficult the knowledge the more individual it becomes.
Of course there are textbooks with selected problems in the selected order that works better than other problems or in other order. We can even explain why these problems and why this order, but I do not believe these explanations, they are explanations in hindsight, they look suspiciously as rationalizations, and they either lack the predictive power, or there is no research trying to falsify their predictions.
It maybe a philosophical take on the problem, but if it is so than pedagogy and psychology is even worse, because it should be their task to explain what happens, how it happens, why learning is indistinguishable from doing. Why these problems in this order? Shouldn't we personalize problem sets and their order? How to personalize? Pedagogy says you just try standard approach and if it doesn't work, then try something else, and keep trying different things until something works.
Pedagogy mostly like this, shamanism and black magic. There was alchemy that nowadays considered unscientific, I hope that at some point in the future modern pedagogy will be considered unscientific because it was transform into a science, like alchemy was transformed into chemistry. The science that can take any knowledge, dissect it, and produce a plan of educational activities, that will teach this knowledge to others. And not just this, but I hope the future pedagogy will be able to prove that this plan is the best possible plan, all others will be worse, will need more time, more effort or whatever. I hope that the future pedagogy will forget an idea of a "great teachers" like Feynman, because it will be able to educate anyone to be as a great teacher as Feynman was. It will be a new era, when colleges will easily educate people into Einsteins, Newtons, Archimedeses (how to properly make Archimedes plural in English?), Shakespears, you just name it.
I'll add a couple of anecdotes, to show how little we know on how our mind works.
Sometimes I cannot explain how I managed to understand some topic, and why I struggled with it initially. The last example of this is borrow-checker in Rust. It is simple and obvious now, but at first I fought battles with it and I've lost most of the battles. What have changed in my mind between then and now? I don't really know, I have one guess, but a very vague one: code patterns which I learned the hard way. It is a vague answer because I cannot enumerate the new patterns I learned and the old patterns from C that I was forced to reject. It was just like something clicked in my mind, and now my mind can write Rust code easily. Magic! (Moreover this guess is not my invention, I've read something somewhere in internet, got this idea and it kinda fits in the sense it doesn't contradict to any facts I know. I don't know what happens in my mind when I'm writing Rust and what was happening when I couldn't write Rust.)
There was another example from my undergraduate studies. I struggled with group theory for several months and I couldn't understand what exactly I didn't understand. It seemed like I understood everything and somehow at the same time I understood nothing. At some point something clicked in my mind and I really understood everything. But with this example I know exactly what was wrong: my mental geometric model of groups, factor groups and these things was constructed wrongly. As I fixed it, it started to work wonderfully. And no pedagogy could help me with this, it was a geometric model for internal use only. I'm not sure it is possible to communicate it, and I bet that no teacher would ask me to communicate it. Though if I just talked with someone knowledgeable about group theory in "informal" mode, without strict definitions and proofs, it could probably help me to find my mistake earlier (in "formal" mode I'd catch my mistakes by formal methods and patch them, no one would notice them except me). How to debug something like this in a mind of a living person?