"Cog" word's meaning doesn't follow in joint-word usages like "incognito" and "cognito" which refers to mind and knowledge [closed]

Solution 1:

The root is not cog, but co+gno:

Cognizance:

to know," from Latin cognoscere "to get to know, recognize," *from assimilated form of com "together" (see co-) + gnoscere "to know," from PIE root gno- "to know."

(Etymonline)

Solution 2:

As a follow-on to user121863's answer, one must constantly remember that English is a creole (simplified mashup of) of Anglo-Saxon and French, with half taken from Latin via Old French. Another 10% is taken straight from Latin, and 20% from other languages.

For example, "Fur" and "fury" are pronounced so differently because one is Germanic via Old French, and the other is Latin via Old French. And "fir" is via Old Norse!!