Influencing nonmonotonic reasoning by modifier strength manipulation

Despite the current belief that much common sense reasoning is nonmonotonic in nature, research indicates that only a limited percentage of people are good at nonmonotonic reasoning. Good nonmonotonic reasoners recognize the logical strengths and weaknesses of some arguments. In the present study, we focus on differences in the probabilistic interpretation of the modifiers typically and usually and on the resulting differences in the strengths and weaknesses of arguments. We show that these implicit probabilistic strengths influence the reasoning process of good nonmonotonic