The dignity of a person never collects so many idioms, full of artistic images, as swearing. Opportunity to unburden himself, especially expressively stigmatizing the mental abilities of the opponent, is dear to everyone.
And native speakers of German have made a big contribution to this topic. During the collection of the material, I thought that I would drown under the number of expressions. Frequency is often difficult to determine. I didn’t take outdated ones. Found in texts and included in the popular lists are in bold.
Stupidity can be lack of intelligence, insanity, misunderstanding and error. Let’s start with the first and second, since the border between them is not very clear.