普莱尔早期的时态逻辑思想

Arthur N. Prior's Early Thought of Tense Logic

普莱尔是时态逻辑的创始人,他认为原子命题和带有时态算子的命题都是同样的命题,原子命题只有现在时态,命题的真值随时间的不同而变化。他否定永恒的个体存在,主张充当命题逻辑主语的专名只能指称现存的对象。普莱尔用模态逻辑的方法处理时态命题,比经典逻辑更好地刻画了自然语言表达和日常推理。但是普莱尔的方法也带来了一些问题,比如说它不能命名不再存在的个体似乎有违自然语言的习惯,如何确定时间的单位也成为有争议的话题。尽管如此,时态逻辑仍然发展成内容丰富的逻辑学分支,在许多领域都有着巨大的应用价值。

As the founder of tense logic,Arthur Norman Prior thought that atomic propositions and propositions formed by tense-operators from propositions are all propositions,atomic propositions are only in the present tense,and the truth of propositions will change according to the change of their tenses.He denied sempiternal individuals,and advocated the view that we cannot properly name ob-jects which ceased to exist.Prior handled tense propositions with the approach of ordinary modal log-ic,and his tense logic depicts natural language and everyday inferences much better than classical logic.However,Prior’s method also brings about some problems,such as his inability to name ob-jects which do not yet exist violates the habit of natural language,and how to determine the unit of time becomes a controversial topic.In spite of this,tense-logic has become an important logic branch and is used in many fields yet.