Abstract
The literature on motivated irrationality has two primary foci: action and belief. This article explores two of the central topics falling under this rubric: akratic action (action exhibiting so-called weakness of will or deficient self-control) and motivationally biased belief (including self-deception). Among other matters, this article offers a resolution of Donald Davidson's worry about the explanation of irrationality. When agents act akratically, they act for reasons, and in central cases, they make rational judgments about what it is best to do. The rationality required for that is in place. However, to the extent to which their actions are at odds with these judgments, they act irrationally. Motivationally biased believers test hypotheses and believe on the basis of evidence. Again there is a background of rationality. But owing to the influence of motivation, they violate general standards of epistemic rationality.