I am currently reading Asimov's The Robot Series. I have read The Caves of Steel and now I'm reading The Naked Sun.
In these two books, Elijah orders (on a couple of different occasions) R. Daneel to do something (not really important what that is). The latter refuses, because that would bring the former to harm, thus contradicting the Second Law.
Then Elijah thinks that he could point a blaster at his own head and claim that he was going to kill himself if Daneel didn't execute that order, but doesn't.
A human, (could - would) doubt something like that if Elijah had said it.
So my question is this:
Would/Could a robot doubt the saying of a human?