>> Some natural languages support grammatical features like sub-clauses but that's only "recursive" in the sense that attempts to describe such features (using

>> Some natural languages support grammatical features like sub-clauses but that's only "recursive" in the sense that attempts to describe such features (using formal language grammars) use recursion when in fact and in practice nesting sub-clauses do not "go on forever". Recursion doesn't have to go on forever.