Suffering from executive dysfunction obviates that there is no free will, and it's as if good health is simply having that illusion work out harmoniously.
I think you make a good point that much of what we call thinking is really discourse either with another ^[0], with media, or with one's own self. These are largely mediated by language, but still there are other forms of communicative _art_ which externalize thought.
The other thoughts here largely provide within-indivudal examples: others noted Hellen Keller and that some folks do not experience internal monologue. These tell us about the sort of thinking that does happen within a person, but I think that there are many forms of communication which are not linguistic, and therefore there is also external thinking which is non-linguistic.
The observation that not all thought utilizes linguistic representations (see particularly the annotated references in the bibliography) tells us something about the representations that may be useful for reasoning, thought, etc. That though language _can_ represent the world it is both not the only way and certainly not the only way used by biological beings.
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