The Lexicon: A Cornucopia of Wonderful Words for the Inquisitive Word Lover
By: William F. Buckley Jr.
This boon to logophiles, culled from Buckley: The Right Word, presents
the author’s most erudite, outré, and interesting words - from
prehensile and sciolist to rubric and histrionic - complete with
definitions, examples, and usage notes. Introduction by Jesse
Sheidlower; illustrations by Arnold Roth.
Google Books gives the definition of sciolist (in William Buckley’s lexicon) as:
sciolist (noun) One whose knowledge or learning is superficial; a pretender to scholarship.
“I don’t believe you. You are an unaccomplished fake. An academic sciolist.”
https://en.wiktionary.org/wiki/sciolism#English
sciolism - 1st appearing in early 1800s.
The practice, or an instance, of expressing opinions on something
which one knows only superficially or has little real understanding
of.
In the search, I came across this interesting study: The Dunning–Kruger Effect: On Being Ignorant of One’s Own Ignorance
https://www.demenzemedicinagenerale.net/images/mens-sana/Dunning_Kruger_Effect.pdf