对三个悖论的消解  

The resolution of three paradoxes

作　　者：杨六省 

机构地区：[1]长安师范学校,陕西西安710100

出　　处：《宝鸡文理学院学报（自然科学版）》2011年第3期25-29,共5页Journal of Baoji University of Arts and Sciences(Natural Science Edition)

摘　　要：目的讨论意外考试悖论的自然语言版本、蒙塔古-卡普兰版本以及知道者悖论诸论证的有效性问题。方法以一条叫做逻辑先后律的思维原则为工具,对所论问题进行剖析。结果 (发现)①对第二天是否考试的判断环节的缺失,使问题无法讨论及论证无效;②意外考试悖论的自然语言版本中,不能推出"最后一天不可能考试"的结论;③意外考试悖论的蒙塔古-卡普兰版本中,合理假定(C4)非恒真;④知道者悖论的推理前提,是一个不合逻辑的定义。结论上述三个悖论的论证均是无效的。Aim To discuss the effectiveness of the justification of the surprise examination paradox which is both in natural language version and R.Montague-D.Kaplan version,and also of the knower paradox.Methods With a thought principle called the law of logic order,we analyze the aforesaid problems.Results ① The absence of judgment on whether examination will be conducted on the next day disables problem discussion and invalidates the demonstration.② In the natural language version of surprise examination paradox,one cannot conclude that it is impossible for the last day to be the examination day.③ In R.Montague-D.Kaplan version of surprise examination paradox,the reasonable assumption（C4） is not constantly true.④（One of） the premise（s） of the surprise examination paradox is an illogical definition.Conclusion The justification of the three said paradoxes is invalid.

关 键 词：不合逻辑定义 卡普兰 知道者悖论 逻辑先后律 蒙塔古 意外考试悖论 

分 类 号：O144.2[理学—数学]