“The real evil of the world,” said Carlo to the ghost of Umberto Eco “is one and only: ignorance!".

"It's actually semi-ignorance," the professor said.

"What do you mean?"

"What I mean is that healthy and complete ignorance does not harm. For example, when I was alive and living in my house in Milan, I knew nothing about electrical systems and was completely oblivious to the subject. Therefore, aware of it, I relied completely on my electrician. This is because total ignorance is also accompanied by fearful respect for the ignored argument, and consequently humility. Instead, if I had read two or three textbooks at the same time and, convinced that I had assimilated knowledge, had decided to make my own electrical system, I would probably have set my invaluable library on fire."

"So, are you telling me that having some knowledge is more harmful than knowing nothing at all?"

"Exactly, especially if associated with another very common characteristic."

"Would it be?"

"The bullshit."