由于现实问题的极端复杂性,我们不可能一下子理解其全部的内在联系;而且,这些内部关系对于理解我们所研究的特殊现象,也并不具有同样的重要性。因此,合理的研究程序应当是:根据我们的目的选择与我们研究问题相关的基本因素和基本关系,然后把我们的研究集中于这些因素和关系上。 Because of the extreme complexity of real problems, we can not immediately understand all of their internal relations; moreover, these internal relations are not equally important for understanding the special phenomena we have studied. Therefore, a reasonable research procedure should be to choose the fundamental and fundamental relationships that are relevant to our research questions for our purposes, and then focus our research on those factors and relationships.