On the Reduction of Deontic Logic and the Interrelated Problems

Key words: 
• deontic logic

Abstract: Anderson holds that deontic logic can be reduced to alethic modal logic by the reduction formula Op(口(～p?S).But his opinion is unsound. All standard systems can not include the formalization as their theorem of 'It ought to help a man who is robbed and robbery is forbidden'. The good Samaritan paradox belongs to the class of paradoxes that result from the fact that a formula A is a theorem of a formal system, but a actual example of A should be ejected.