He was unkempt and disheveled, even by the standards of those primitive living people of the tribe. If you could find a translator to speak with his tribes-folk, they’d not be offended to hear you refer to him as a madman. They’d find it surprising that you considered that some sort of insightful revelation.
They would part company on two points. First, you believe the fact that he thinks he speaks to spirits and devils is evidence of his insanity. They believe the fact that he has to speak with spirits and devils has made him coo-coo. Who wouldn’t lose a few screws? Second, where you think his insanity makes him fit for nothing — incapable of a worthy contribution. They think his insanity makes him uniquely fit to do a task no sane person would ever do.
He lives by himself, outside the tribe’s clearing, and people only have the nerve to visit when they must. But he’s never for lack of a conversational companion. Though only occasionally does he speak in the tribe’s language. He’s just as likely to caw like a crow. He fears nothing, even those things sensible people would agree are rightly feared. The tribespeople fear him, but they value him for the fear he inspires — in those unseen things that bump in the night and in their souls.
With one foot in this world and the other in another, his world bears only a passing resemblance to yours.