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. The reasoning in the commentator's argument is most vulnerable to criticism on the grounds that the argument ['infers that a certain condition is required for success from the fact that the lack of that condition is associated with failure', 'ignores the possibility that the conditions that are necessary for the welfare of the people are likely to change over time', 'appeals to evidence from sources that are likely to be in some way biased or unreliable', 'infers the necessity of a certain condition for success from the fact that its absence has always led to failure']