I was at the Lowy Institute today for a talk on Asia’s Nuclear Power Future. The Chair announced that the event was being held under the Chatham House Rule. The rule reads:

“When a meeting, or part thereof, is held under the Chatham House Rule, participants are free to use the information received, but neither the identity nor the affiliation of the speaker(s), nor that of any other participant, may be revealed.”

There is only one rule, that is why it is called the Chatham House Rule. Not Rules. As seen with this recent article, many people in the media and public discourse continue to give the rule plurality. There is only one rule, so the correct form is the singular Rule. Now I hope I do not sound like a pedant.