I really and truly think I might know what “the oldest question in the universe” mentioned on this season of Doctor Who is. And the answer really has been hidden in plain sight. But before proceeding, presumably I should quote the Doctor and say…
The question has been in our view (“hidden in plain sight”) ever since they announced the title of the season finale, which is going to be “The Wedding of River Song.” Ever since the Doctor first met River Song and she knew his name, and he wondered why he would tell her his name.
The oldest question in the universe is perhaps:
“Will you marry me?”
– or, since time travel makes it possible for that question to be asked later in the universe’s history than this one, it might be:
“Do you take this man/woman to be your lawfully wedded husband/wife?”
For those who have suspected that the question might be “What is the Doctor’s name?” my suggestion is not entirely unrelated. At one’s wedding, they have to be asked and answer the question using their own real name and not aliases.
They could well cut to someone whispering in the audience when the questions that name the Doctor are asked, rendering his name inaudible. But I am starting to think that we have known the Doctor’s name for a very long time, and that that too has been hidden in plain sight.
What if the Doctor’s parents named him “Silence”?
I’m still not certain whether the Gallifreyan word for “silence” might not simply be silence – the absence of sound – which would agree with his previous statement that his name is unpronounceable. But it could also be that the Doctor decided that being silent about his name would be an amusing construal of his name.
And so the meaning of the prophecy that “Silence will fall” depends on the answer Melody Pond gives to the question(s) “Will you marry me?” and/or “Do you take this time lord…?” Either Silence will fall, and the Doctor will die, or Melody will say yes and will find a way to save him, and The Silence will fall.