On 05/05/2017 09:36, Victor Miller wrote:
Is there some trick? If Linda is married, then the Linda-John pair is the married/not married pair. If Linda isn't married then the Paul/lLinda pair is the one.
The only trick is that a surprising number of people, even rather clever people, get only as far as figuring out that they can't tell whether L&J are married nor whether P&L are married, and conclude that the answer to the question is no. I think it likely that training in mathematics correlates strongly with answering this correctly. I am not sure how the explanation for this, if I'm right, should be divided between the effect of learning about logic and the effect of being the sort of person who is willing to spend time learning about logic. -- g