我们的同志必须明白，我们学马克思列宁主义不是为着好看，也不是因为它有什么神秘，只是因为它是领导无产阶级革命事业走向胜利的科学。直到现在，还有不少的人，把马克思列宁主义书本上的某些个别字句看作现成的灵丹圣药，似乎只要得了它，就可以不费气力地包医百病。这是一种幼稚者的蒙昧，我们对这些人应该作启蒙运动。… - Mao Zedong

中国古代有个寓言，叫做“愚公移山”。说的是古代有一位老人，住在华北，名叫北山愚公。他的家门南面有两座大山挡住他家的出路，一座叫做太行山，一座叫做王屋山。愚公下决心率领他的儿子们要用锄头挖去这两座大山。有个老头子名叫智叟的看了发笑，说是你们这样干未免太愚蠢了，你们父子数人要挖掉这样两座大山是完全不可能的。愚公回答说：我死了以后有我的儿子，儿子死了，又有孙子，子子孙孙是没有穷尽的。这两座山虽然很高，却是不会再增高了，挖一点就会少一点，为什么挖不平呢？愚公批驳了智叟的错误思想，毫不动摇，每天挖山不止。这件事感动了上帝，他就派了两个神仙下凡，把两座山背走了。现在也有两座压在中国人民头上的大山，一座叫做帝国主义，一座叫做封建主义。中国共产党早就下了决心，要挖掉这两座山。我们一定要坚持下去，一定要不断地工作，我们也会感动上帝的。这个上帝不是别人，就是全中国的人民大众。全国人民大众一齐起来和我们一道挖这两座山，有什么挖不平呢？

下定决心，不怕牺牲，排除万难，去争取胜利。

Hence, if in any process there are a number of contradictions, one of them must be the principal contradiction playing the leading and decisive role, while the rest occupy a secondary and subordinate position. Therefore, in studying any complex process in which there are two or more contradictions, we must devote every effort to funding its principal contradiction. Once this principal contradiction is grasped, all problems can be readily solved. This is the method Marx taught us in his study of capitalist society. Likewise Lenin and Stalin taught us this method when they studied imperialism and the general crisis of capitalism and when they studied the Soviet economy. There are thousands of scholars and men of action who do not understand it, and the result is that, lost in a fog, they are unable to get to the heart of a problem and naturally cannot find a way to resolve its contradictions.