How do you know what's true?
I want to know what epistemology the candidates subscribe to. When a candidate says that he knows something, or states a fact, I'd like to have a general idea about how he knows those things. Was it a voice in his head, a gut feeling, a reasoned position, or what?
Nothing is more important than this, in an era where facts no longer seem to matter to half the country.
That's more of a philosophical question than a scientific question. It's a good question, though.
A beautiful, succinct question.