When doctors don’t know the cause of your ailment they may refer to it as idiopathic. It’s sort of a polite way of saying, “It’s just you.”
When I see the word idiopathic I think there should be another word, idiopathy. If sympathy may be summed up as, “I feel your pain,” then idiopathy may be summed up as, “I feel your stupidity.” [Alternatively, "I feel you're stupid."]
I’ve been fairly swimming in idiopathy this week — it was semester exam week. And I’ve decided that idiopathy sometimes just isn’t enough to express how I feel when, for example, a student shows up for an exam without a pencil. We have moved into idiopathetic territory at that point.
As a teacher I am a soldier in the war against ignorance. Unfortunately, while education is effective against ignorance, some other cure [if one exists] must be found for stupidity.