"Within Western traditions, forgiveness has often been regarded as a “high” and “difficult” virtue (Scarre 2004), and its opposite, unwillingness to forgive, as a vice. Yet this poses an immediate problem of interpretation, namely, whether forgiveness is a “high” and “difficult” virtue in the sense that while it is morally laudable it is beyond duty (i.e., supererogatory). Since supererogatory actions are permissible, not obligatory, it follows that a failure to forgive, at least in circumstances where forgiving would be supererogatory, would not, contrary to the aforementioned view, be a vice. However, widespread and persistent disagreement within moral philosophy both about supererogation and the deontic nature of forgiveness have led to conflicting views on the relation between forgiveness and moral obligation (see, e.g., Gamlund 2010; Lauritzen 1987). Some thinkers have argued that forgiveness is a duty (Rashdall 1907) while others have maintained that, like a gift with no strings attached, forgiveness is utterly gratuitous (Heyd 1982). It might also be thought that, similar to the duty of charity in Kant’s moral system, forgiveness is properly regarded as an imperfect duty. Unlike perfect duties such as the obligation to justice or honesty, imperfect duties allow for agential discretion over when and with respect to whom to discharge the duty. In this way, forgiveness may be located in a system of moral duties that allows for no supererogatory deeds at all."(
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