That doesn't prove anything, but from an etymology perspective both "conscious" and "cognition" mean "know together". One can easily spot the common "co-" prefi

That doesn't prove anything, but from an etymology perspective both "conscious" and "cognition" mean "know together". One can easily spot the common "co-" prefix which carries the "together" part, but the main roots derive from different verbs which have respectively the alternative meanings of "distinguish, dissect, split" and "recognize", respectively. As often, the definition of "recognize" is definitely circular so it seems that it is the "real root" for "knowledge", while "conscious" seems to have an "analysis" flavor. IMO, "understanding" is synonym to intelligence, and the ability to analyze is one keep part of it (another is the ability to recombine). So it seems that we can agree that "without consciousness there can be no understanding", although we moved away a bit from the common meaning of "conscious".