In what circumstances is the word 'no' open to interpretation?
Certainly in date-rape terms, it has been a popular conundrum put forward by desperate defence lawyers, predominantly when their client is guilty.
In the context of the classic relationship question, 'Do I look fat in this?', the snappy 'no' retort is perhaps more rhetoric in nature.
But in journalism, it is one of those responses that tends to come across with abundant clarity. It is the opposite of 'yes'.
Last month, for example, a business reporter called investment bank Goldman Sachs with a simple question.
Would Michael Carr, the head of investment banking in Asia (ex-Japan), be leaving Hong Kong and returning to New York?
Rumours of management shuffles were plentiful, and this was one of the more solid ones.