I only read the first post.
My opinion is that language is instictually "learned". Not in the way you may think though. I don't mean we are born with a form of communication. We are born with the capability of learning.
It won't take more than a few hours for me to learn to communicate with a person who only speaks Russian. At first we will only use body language and sounds. But given enough time, we will build on our communication system. We will develope a code, an agreed upon set of symbols/sounds that represent intent.
It won't take to long for me to figure out that a certain facial expresion, coupled with a threatening sound and movement will be followed by an a#$ wipping.
Language grows. It is as simple as that. All we do is find a set of symbols we can agree upon and tweek it occasionally in order to be able to better communicate our intentions.
Language is no mystery. Leave a few babies alone for generations, keep them alive, and they will develop a system of symbols that allows them to communicate. It will be very rough at first, but given the ammount of time we have had to work on it, they will agree upon a complicated system of symbols that allow them to communicate perfectly. Then, we will be able to translate their language into ours, because every piece of their language will have derrived from the basic need that spurred communication. The need to express intent. Languages are formed in a specific order. 4 levels of language which are from the lowest level to the highest; statistics/alphabet, syntax/grammar, semantics/meaning, pragmatics/intent.
It is very simple really. We need to communicate, so we look for ways to express our intent. We end up creating physical, audible, visual, or written symbols and then agree upon a system of those symbols with another in order to be able to express our intent.
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