Commentator: The Duke of Acredia argued long ago that only virtuous Acredian rulers concerned with the well-being of the people will be able to rule successfully  Since then, when Acredian governments have fallen, their falls have always been during the rule of one who viciously disregards the people' s needs
The Duke, then, was right about at least one thing: Concern for the welfare of the people is necessary for the successful governance of Acredia
infers that a certain condition is required for success from the fact that the lack of that condition is associated with failure