When Observers can't figure something out by, well, Observation, they research. And when they can't do that, they ask questions. They kinda have to know everything, don't they?

"No. I only arrived today." A beat, and a realisation comes to him. "I do not understand such concrete harnessing of emotional energy, but I suspect that it is similar to harnessing of mental energy. I see it is something that nonhumans do, as well."

The way he says 'nonhuman' he might as well have been referring to New Yorkers or people with brown eyes. There is nothing associated with the term in his voice.