I thought about learning languages at the gym a while ago. In particular, why do children (regardless of intelligence) find it so easy to learn a language, and why do adults (again, regardless of intelligence) find it so hard?
I think this is down to one fact: adults already have a conceptual hierarchy for interpreting the world; children don't. In fact, children don't learn languages as much as concepts, and learning a language – their language – happens en passant as they discover new concepts and refine previously-acquired ones.
Adults, who already have an established hierarchy, cannot (easily) learn a language the way a child does anymore for just this reason. You cannot fill a vessel that is already full, as they say.
It should go without saying that different languages are induced by/induce different conceptual hierarchies, BTW. For example, take the Icelandic words "hurð" and "dyr"; both mean door, yet I understand they refer to distinct concepts. The former (I hope I'm not confusing them again here) refers to the physical door as such, the large, rectangular piece of wood with a handle; the latter, meanwhile, refers to the concept of a door: the opening in the wall through which one passes.
English at least has the word "doorway" for the latter. German, for all I can tell, does not distinguish clearly between the two at all.
The key to learning languages effectively would be to be like a child again, be an empty vessel again. Forget your existing conceptual hierarchies; in particular, do not translate to/from your own language, but rather learn concepts and associate them with words in the new language right away.
This is what otherwise happens when you reach a near-native level, too, and it's why many people never quite make it beyond that point: they suddenly have to switch strategies, think differently and approach learning in a different way to make further progress.
When you start learning a new language as an adult, you typically abstract from an object to the word referring to it, then translate that, and then concretize to the object in question again, like so (using the example of a German person learning English):
|German word||↔||English word|
The goal, then, is to do this instead:
In other words, the goal is to think in English (i.e., the language you want to learn).
This isn't limited to languages, either, BTW. Ever wonder why you're comfortable calculating in base 10 but why you'd likely be lost in, say, base 8? Same reason; you grew up with base 10, and it shaped how you view numbers.
And in order to calculate in base eight, chances are you have to do this:
|318 × 478||17178|
|2510 × 3910||=||97510|
Rather than this:
|318 × 478||=||17178|
Compare that with the above. Look familiar?
Obviously I'm more interested in learning languages than calculating in bases other than 10, though. And how useful the above will be in practice remains to be seen, though I think it will influence how I approach and learn languages — and for the better. I'm not one of those savants who can learn a new language in a week, but I think it'll be able to help me be a better learner.
Also, Unicode really needs a "LEFT RIGHT DASHED ARROW" character.