Peter

Certainly the institutions and the legality add problems. The core of it is: there's an old idea in philosophy that knowledge is "justified true belief", and then someone called Gettier kept coming up with situations where there were true beliefs where something was up with the justification. However I think I prefer my hypotheticals to his.

There was an incident in an RPG I was once playing. In the Warhammer 40,000 universe, there are psykers - people with psi powers. We were playing a group working for the inquisition. As far as we were concerned, psykers came in two types; sanctioned and unsanctioned. Sanctioned psykers were OK, we had one in our party. Unsanctioned psykers... there's a procedure for sanctioning them, but for those without the authority to do so, it's kill on sight.

In our party, we had the Assassin, the Scum (basically a con-man character) and the Sanctioned Psyker. Previously there had been incidents that caused the Assassin to hate the Scum. Also the Scum got corrupted by Chaos, and mutated, and developed psyker abilities, which he kept secret. Then there was a fight with some space dwarves. The Sanctioned Psyker used an ability, and had a freak psychic accident that caused him to swap minds (well, bodies - the bodies stayed in place and the minds switched) with the Scum. The Sanctioned Psyker, in the Scum's body, then proceeded to use a highly visible psi power for self-protection. The Assassin saw this, shouted "Unsanctioned Psyker!" and proceeded to try to gun the Scum down. And I thought: I've read web pages on philosophy that deal with this sort of thing.