The evidence is that action of psychoactive drugs, especially psychedelics and anaesthetics. We have compounds that we have studied that actions of and they act on neurons and their networks to alter or eliminate cognition.
I understand there is data that supports this theory; I wasn’t aware that it is definitive nor how easily it could be reproduced.
Before it was edited, your original statement framed certainty about cognition originating in chemistry as a personal belief. Which isn’t a scientific statement.
Edit: as a side note, general anesthesia is used hundreds or thousands of times daily and it always eliminates or reduces cognition. That's literally the whole purpose of using it
https://neurosciencenews.com/psychedelics-consciousness-2028...
kinda fascinating…
Interesting point re: GA.