Chinese and overseas experts have done various theoretical probations concerning China's modernization in the early phase, which can be roughly divided into two interpretational models: "internal-cause theories", and "external-cause theories".
It reappeared in this course that the views of "develop the useful and discard the useless" , "inner reason" and "outer reason" of Materialistic dialectics, embodied in turn the rule of "flectional development", "motivity of inner contradiction" and "extroversion of inner contradiction" of scientific theory.