A FAULTFINDER's defining activity is to CRITICIZE — it's their core function. An arbitrator's defining activity is to mediate — that is precisely what they do by role. Both pairs = [person defined by a role] : [the action that defines that role]. 'Luminary:recognize' and 'pharmacist:prescribe' are weaker because prescribing is part of a pharmacist's job but not their sole defining function.