There have been debates as to whether civil disobedience must necessarily be non-violent. Black's Law Dictionary includes non-violence in its definition of civil disobedience. Christian Bay's encyclopedia article states that civil disobedience requires "carefully chosen and legitimate means," but holds that they do not have to be non-violent. It has been argued that, while both civil disobedience and civil rebellion are justified by appeal to constitutional defects, rebellion is much more destructive; therefore, the defects justifying rebellion must be much more serious than those justifying disobedience, and if one cannot justify civil rebellion, then one cannot justify a civil disobedients' use of force and violence and refusal to submit to arrest. Civil disobedients' refraining from violence is also said to help preserve society's tolerance of civil disobedience.