The scientificity and truth of Marxism lies in its scientific world outlook and methodology, in its representation of the interests of the overwhelming majority of the people, and in the openness and advancement of its theoretical system. The practice of China's revolution, construction and reform has proved the scientificity and truth of Marxism. The truth of Marxism is that it absorbs all the achievements of civilization created by predecessors, especially the achievements of natural science and social science from the end of18th century to the middle of19th century. Marxism emerged not only with the emergence of modern science and technology, but also with the development of modern science and technology. Secondly, it reveals the historical trend that capitalism is bound to develop towards capitalism, determines the people's historical dominant position, and puts forward the historical mission of the proletariat to liberate all mankind and itself. Based on the historical position at that time, make reasonable inferences about the future of human society. It is rooted in the practice of human development and progress, keeps pace with the times, and will never turn basic conclusions into rigid dogmas. Third, it is supported by economics. The historical view guided and summarized by dialectics scientifically proves the belief of * * * productism. Marx used economics to prove that capitalism is bound to perish and socialism is bound to win. His economic proof of his belief in productism is itself a proof of his historical view. Marxism's proof of * * * productism is first of all the proof of economics and history. Then philosophy summarizes this proof. The truth of Marxism also lies in "it is very complete and strict", and it is a life belief that is consistent with subjective and objective, integrated with knowledge and practice, and can stand the test of practice. The practice of Marxism is mainly embodied in the * * * production movement. On the one hand, the * * production movement was initiated and developed with the encouragement of this belief. On the other hand, every development and success of this movement has provided new proof for Marxism.