"Oh, come now--"

Arthur knows a crazy person when he sees one, having been one himself at one point, and he wouldn't believe for a moment that the Doctor was insane. Of course, he could be a whole different level of crazy..

The explanation is satisfactory though, and he nods, then shakes his head again as the effects of the cordial slowly begin wearing off. He'll take a moment, he thinks, before he tries it again.

"What was Gallifrey like?"