The paper introduces the theories of H.Reichenbach and Karl Popper, analyzes their defects and points out that the human practical activity is the only way to exam the rationality of knowledge.

• 本文著重介绍了莱欣巴哈和波普尔关于归纳问题的理论，并对两者理论的缺陷进行了分析，指出归纳只有在人类的实践活动中去检验知识的合理性。