Abstract: Mele explores two kinds of motivated irrationality and reviews philosophical literature on them: akratic action (action exhibiting so-called weakness of will or deficient self-control) and motivationally biased belief (including self-deception). When agents act akratically, they act for reasons, and in central cases, they make rational judgments about what it is best to do. Although the rationality required for that is in place, 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.

Keywords: action, akrasia, background of rationality, epistemic rationality, explanation, motivationally biased belief, irrationality, paradox, self-deception, weakness of will,