Like truth, a 'fact' is a lie that contestants tell themselves is correct and confirmable. These have no basis in reality and are of no use on the Island. Moreover, possession of 'facts' is strictly regulated by multiple Island government agencies that impose significant fines on contestants who have too many.
Most clans oppose 'facts' on purely philosophical grounds and have been known to rally all their members to attack contestants1) who claim to know facts.2)