Cassian has no doubt in his mind that if Istredd wanted to understand technology - even something like a bike - would be easy for him to grasp. Putting together a bike is similar enough to learning a spell from a book. There were just more parts. He's probably simplifying it, but it's as close to a metaphor as he can manage.

His brow furrows some as he sits himself on the ground in order to clean the screw. "A psychic?" It's not a phrase he's heard used before, but he figures he can draw broad strokes about what it could possibly mean based on what he's seen and knows. Then again, he doesn't have a problem asking questions to clarify when he doesn't know as much as another. "What is that?"