There has been talk of how to answer a negative question without ambiguity, most often with a qualifying phrase needed for clarification. (For example, "yes, I do"/"no, I don't.) I've noticed that ...
The Germans have doch and the French have si as a word that means "yes" in response to a negative question, such as: Don't you want some ice-cream? Yes [I do]! In English, we only have yes (as ...