When Gordon Wilson's daughter died in the rubble at Enniskillen, he forgave the terrorists who had murdered her. But the mother of Lesley Ann Downey, the child tortured and murdered by Ian Brady and Myra Hindley, never forgave her killers. Eric Lomax survived a Japanese prisoner of war camp; after many decades, one of his torturers contacted him in profound remorse. Eventually, Lomax forgave him. Simon Wiesenthal, imprisoned in a concentration camp, was asked for forgiveness by a dying Nazi who had burned 300 Jews alive. Wiesenthal withheld forgiveness.
Is forgiveness always the right thing to do? Or can it be more moral to refuse to forgive a wrongdoer?
On the whole, forgiveness gets a good press in our culture. It is widely regarded as being good not just for the offender but also for the forgiver: it enables him or her to free themselves from the role of victim and to get on with life untrammelled by the deadly weight of bitterness and hatred. On this view, forgiveness is seen as being essentially therapeutic: it's good for the victim, and it's good for everyone else, enabling us all to move on and leave the offence behind.
But there is a powerful case against this view. Among others, Jean Améry, the Austrian philosopher who survived Auschwitz points out that many victims are not primarily concerned with personal therapy; what they often care most about is justice, both for themselves and for the silenced dead. Améry felt that, unless the perpetrators of the horrors enacted on the Jews of Europe finally understood their guilt and stood in utter repentance alongside the victims - which they were never going to do - then forgiving them was a way of glossing over the atrocities that they had committed.
He preferred to remain on the side of justice, rather than collude in a general erasing and forgetting of what the victims had undergone. Similarly, Esther Mujawayo, one of the survivors of the Rwandan genocide of 1994, said that forgiveness was primarily an obsession of the NGO personnel who came from outside to work with the survivors, and of the government who had somehow to restore civil society; but she herself, like many other victims, was not interested in forgiveness. She felt that victims had every right to maintain hostility towards those who carried out the genocide.
If forgiving involves forgetting, or "wiping the slate clean", then the case against it seems overwhelmingly strong. How could anyone presume to tell the mother of a child who has been murdered that she should forget what happened to her child, or cease to condemn it? But we don't have to think of forgiveness as a matter of forgetting: there is another conception of it that sees the essence of forgiveness not as forgetting what was done - still less as excusing it - but rather as a means of overcoming the (understandable and justifiable) hatred the victim has for the person who has harmed him or her. We can give up on hate without abandoning remembrance, or condemnation, of the offence. Indeed, the forgiver can still call for the offender to be punished for the sake of justice, or in order to bring him to some better understanding of the horror of what he has done.
What forgiveness does rule out is seeking personal satisfaction in the suffering that the punishment causes the offender. Hatred is what forgiveness rejects, not remembrance and not the demand for justice.
Victims have a right to hate the perpetrators but not a duty to do so. And there can be good reasons to refrain from doing something even though we have a right to do it. One such reason in the case of forgiveness may lie in the knowledge of our common human susceptibility to evil, and in the painful remembrance that even the worst of perpetrators is still a member of the human family.
Refusing to forgive can sometimes be morally admirable, especially in pursuit of a campaign for justice. But forgiveness, in its rejection of hatred, can also be morally admirable: its generosity and human solidarity offer us a kind of hope, however fragile, for a better future.
Eve Garrard is an Honorary Research Fellow in the Department of Philosophy, University of Manchester. 'Forgiveness', by Eve Garrard and David McNaughton is published by Acumen Publishing at £9.99.
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