In the thread below on knowing who, David Braun suggests that statements like the following sound contradictory.
‘Zaphod Beeblebrox kissed that guy’ is an answer to the question ‘Who did Zaphod Beeblebrox kiss?’, and B knows that Zaphod Beeblebrox kissed that guy, and so she knows an answer to the question of who Zaphod Beeblebrox kissed, but she does not know who Zaphod Beeblebrox kissed.
I think this sounds fine in some cases, or at least if it doesn’t this tells us something about what counts as an answer to a question.
Let’s get some background. As President of the galaxy, Zaphod legalised gay marriage, so ‘that guy’ denotes in the context his husband. Last night Zaphod was at a party where by all accounts he kissed celebrities from every major star system. He also gave that guy a goodnight kiss. The identities of the celebrities are a mystery. B knows that Zaphod kissed his husband, but not the mysterious celebrities.
Now what about David’s sentence? I think B doesn’t know who Zaphod kissed. She does know that he kissed that guy. Is ‘Zaphod kissed that guy’ an answer to the question of who Zaphod kissed? I’m half-tempted to say it is, so here’s a case where David’s ‘contradictory’ sounding sentence is true. But maybe I’m missing something crucial about the semantics of plurals and/or questions here.