Allowing for Exceptions

You find yourself in a court of law, accused of having hit someone. What can you do to avoid conviction? You could simply deny the accusation: ''No, I didn''t do it''. But suppose you did do it. You may then give a different answer. ''Yes, I hit him'', you grant, ''but it was self-defence''; or ''Yes, but I was acting under duress''. To answer in this way-to offer a ''Yes, but. . .'' reply-is to h...