中文摘要：

溯因推理为归纳与演绎推理之外的另一种重要的推理形式，在人工智能等领域有着广泛的应用．通俗地讲，溯因推理是从观察（结果）去推断原因的推理过程．不同于以往的研究思路，通过使用本原蕴含式和素蕴含，证明了可以把命题逻辑和命题模态逻辑系统S5中求溯因问题的极小解释转化为求对应集合的极小碰集问题．给出了求解溯因问题的一种新方法．

英文摘要：

As important type of reasoning besides induction and deduction, abduction has been widely used in many areas, such as AI. Generally speaking, abductive reasoning is the process of inferring causes from the observations. Unlike past research, which uses prime implicate and prime implicant, this study proves that seeking minimal interpretation of abductive problem for propositional logic and propositional modal logic system $5 can be reduced to the problem of seeking minimal hitting set in the corresponding set, and presents a new method for solving abductive problems.