Comment by chmod775

"Thought is language" is a folk intuition that has been proven wrong over and over. People with severe global or agrammatic aphasia still can score higher on intelligence tasks than you'd expect - even though this data generally comes from people who suffered a stroke, which generally isn't neatly contained to one's language capability. Also, more importantly, even in people with full brain function, the language network appears remarkably unresponsive under neuroimaging when performing arithmetic, logic puzzles, or theory-of-mind tasks. Also famously music tasks: Vissarion Shebalin lost most of his language capabilities to a stroke and still completed his fifth symphony.

There's correlation, and your language network likely augments your intelligence, but as proven by millions of animals, unfortunate humans and also some less-unfortunate human infants, you really don't need language for intelligence.

Where language helps most strongly is metacognition: evidence suggests that it is severely limited without language, and I suppose that is where the common belief that thought is language comes from: the moment you try to think about your thoughts, you use language!

My theory (and this with literally no evidence) is that we use the language network for metacognition precisely because it is not that involved in primary thought. Important to note that "we" here means humans: animals appear to demonstrate metacognition even without language.