If there were a a good reason to believe that irrational thinking--or at least a

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If there were a a good reason to believe that irrational thinking--or at least a certain train of irrational beliefs--leads to greater happiness and prosperity (and I think there is a bit of psych research that suggests this is true), could a rational person decide to think irrationally--to adopt irrational beliefs--and would that itself be a rational decision?