DUNCE, a slow or stupid person, one incapable of learning. The word is derived from the name of the great schoolman, John Duns Scotus, whose works on logic, theology and philosophy were accepted text-books in the universities from the 14th century. "Duns" or "Dunsman" was a name early applied by their opponents to the followers of Duns Scotus, the Scotists, and hence was equivalent to one devoted to sophistical distinctions and subtleties. When, in the 16th century, the Scotists obstinately opposed the "new learning," the term "duns" or "dunce" became, in the mouths of the humanists and reformers, a term of abuse, a synonym for one incapable of scholarship, a dull blockhead.
Note - this article incorporates content from Encyclopaedia Britannica, Eleventh Edition, (1910-1911)