The info you are using to build the knowledge of your new language, where is it coming from? From the outside? (listening to and reading people who communicate using the language) or from the inside? (your own assumptions about the grammar, the vocab and the sounds of the lang.)
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Both. The system can *only* run on comprehended linguistic input. But only human neural architecture (UG + parser etc) can turn language into Language. And that process is *not* conscious (other than awareness of meaning).