Rulers can't be an expert in all the domains they oversee. Thus the test you speak of should be whether they can build a team of experts and harness that collec

Rulers can't be an expert in all the domains they oversee. Thus the test you speak of should be whether they can build a team of experts and harness that collective expertise to make good* decisions. Alternatively you could pick the person who's decisions have most often turned out to be good* ones, and hope that they continue making good* decisions. * For whatever you think is good.