There is a book every good Swedish mother reads to her children to instill in them toothbrushing habits that will keep for the rest of their lives. Karius och Baktus, written by Norwegian author Thorbjørn Egner, follows the adventures of two teeth-trolls and their good life in little Jan's mouth. Jan, you see, refuses to brush his teeth, and the two teeth-trolls build houses in his molars, stick their little picks in his nerve, and finally meet their demise.
When my mamma was young she thought bacteria looked exactly like Karius and Baktus and would scrutinize the sink hoping to see a very, very small trolls with bright bushes of hair atop their heads. Whenever she found a tiny dot of something, she would be satisfied knowing she had brushed them away and sent them to a watery grave.
The problem is, despite knowing they are bad little trolls, I always felt a bit sorry for them. Perhaps I felt Jan was a stupid fellow for neglecting to brush his teeth in the first place.