A word that describes "false sense of knowing" [duplicate]

Solution 1:

Answering a question like this is almost impossible, because meaning is generated from several sources other than a dictionary.

It is generated in presupposed encyclopedic knowledge (Langacker's 'base'), in contextual experience (Frege's 'sense'), and in contextual knowledge (Filmore's 'frames'),and the use to which an utterance is put, so without access to your thoughts it is a very difficult task!

... but here is my vote anyway: misconception.

" The action or an act of misconceiving or misunderstanding something. Now chiefly: a view or opinion that is false or inaccurate because based on faulty thinking or understanding." (OED)

Solution 2:

Words like misconception, false impression, delusion, or fallacy come to mind. If I were you, I'd look them up and see if any of them matches what you're looking for.

As for your example, I'd simply say that someone is under the false impression of being fully informed, or that they've been mislead to believe that they're fully informed.

I don't think you'll find a single word that has the same meaning, but if you want to look into it, I recommend you go to www.thesaurus.com and look for words with a meaning similar to the words that have already been mentioned here.