What a good thing it would be to humiliate and hold up to ridicule that dudish boy, always smartly dressed, with head erect and serene look! It would be a deed of charity, so the charitable professor applied himself to it with all his heart, slowly repeating the question.
"The book says that the metallic mirrors are made of brass and an alloy of different metals--is that true or is it not true ?" "So the book says, Padre." "_Liber dixit, ergo ita est_.

Don't pretend that you know more than the book does.

It then adds that the glass mirrors are made of a sheet of glass whose two surfaces are well polished, one of them having applied to it an amalgam of tin, _nota bene_, an amalgam of tin! Is that true ?" "If the book says so, Padre." "Is tin a metal ?" "It seems so, Padre.

The book says so." "It is, it is, and the word amalgam means that it is compounded with mercury, which is also a metal.

_Ergo_, a glass mirror is a metallic mirror; _ergo_, the terms of the distinction are confused; _ergo_, the classification is imperfect--how do you explain that, meddler ?" He emphasized the _ergos_ and the familiar "you's" with indescribable relish, at the same time winking, as though to say, "You're done for." "It means that, it means that--" stammered Placido.
"It means that you haven't learned the lesson, you petty meddler, you don't understand it yourself, and yet you prompt your neighbor!" The class took no offense, but on the contrary many thought the epithet funny and laughed.