 What is the true exhaustive answer to (9) in a world where Ann is coming and Bill is coming as well? One option is the proposition \(\{w\): Ann and Bill are both coming in \(w\}\), but another option is the proposition \(\{w\): if Ann is coming in \(w\) then Bill is also coming in \(w\}\). It is not quite clear pre-theoretically which of these two options is more suitable. Notice that if we pick the second option, then we must assume that the true exhaustive answer to (9) in a world where Ann is coming but Bill is not coming is \(\{w\): if Ann is coming in \(w\) then Bill is not coming in \(w\}\). And this would mean that these two ‘exhaustive’ answers actually overlap (they both contain all worlds where Ann is not coming) and thus do not form a partition. This may be considered a reason to pick the first option instead. However, this line of reasoning is purely theory-internal; it seems impossible to decide on theory-external grounds what the true exhaustive answers to a conditional question should be taken to be. 