First, humans are part of nature, and humans depend on nature for their existence. Marx and Engels sorted out the evolution and development of human beings from the perspective of the history of human development and evolution, and proposed that human beings are the product of the evolutionary development of nature. Human beings originate from nature, are part of nature, and rely on nature for their existence and development. Therefore, humans must live in harmony with nature and develop in a coordinated manner. When Marx and Engels discussed the relationship between man and nature, they mainly focused on the fact that nature exists prior to mankind itself. Human beings should respect and treat nature well and establish a partnership for the harmonious development of man and nature. In this regard, Marx pointed out: "Man depends on nature to live. ... Man is a part of nature." 〔1〕 (P272). Human beings themselves originated from nature and are the products of differentiation in nature. People should care for and protect nature as much as they care for their own bodies, and live in harmony with nature. Engels said: "We, together with our flesh, blood and brains, belong to nature and exist in nature..." [2] (P519) Human beings themselves are the product of long-term evolution in nature. Human beings cannot exist apart from nature at any time. Destroying the natural environment will endanger the survival and development of human beings. Only by protecting the natural environment can human society develop sustainably. Marx and Engels put human beings specifically and historically into nature to explain the relationship between human beings and nature, and provided a scientific worldview and historical perspective for human beings to correctly view the relationship between themselves and nature.

Second, humans should develop nature rationally. In the second half of the 19th century when Marx lived, although productivity had been greatly developed, the extent of resource development and environmental damage caused by human production activities was still limited. However, Marx and Engels still used their profound theoretical insights to expose and criticize the environmental pollution and ecological damage caused by capitalist production, and elaborated on the idea that humans should rationally develop and utilize nature and realize the harmonious development of man and nature. Marx and Engels once severely criticized human beings for destroying the environment and nature. In early 1868, Marx said in a letter to Engels: “If farming is carried out spontaneously rather than consciously controlled..., what will follow is the desolation of the land, such as in Persia, Mesopotamia and other places. Like Greece". 〔3〕 (P53) Marx and Engels believed that if humans exploit nature uncontrollably and do not pay attention to protecting the ecological environment, they will eventually lead to the destruction of the ecological environment and suffer ruthless revenge from nature. Therefore, humans should rationally develop and utilize nature to achieve harmonious development between man and nature.

Third, human beings should actively transform nature on the basis of respecting the laws of nature. Understanding the laws of nature is the prerequisite for human beings to transform nature. Marx and Engels believed that mankind must better transform nature on the basis of a correct understanding of the laws of nature. Otherwise, it will destroy the ecological balance of nature, trigger an ecological crisis, and ultimately endanger the survival and development of mankind. Human beings' treatment of nature is a process from blind control and conquest to scientific utilization. Only by correctly understanding the laws of nature and acting in accordance with them can humans truly receive the gifts of nature, and only then can nature show its beautiful and gentle side to humans. Otherwise, humans will suffer nature’s ruthless revenge. In this regard, Marx once quoted the scholar Tremer's point of view: "Human plans that are not based on the great laws of nature will only bring disaster." 〔4〕 (P251) Engels enumerated Mesopotamia , Greece, Asia Minor and other regions did not follow the laws of nature and caused devastating ecological disasters due to excessive deforestation; the Italians in the Alps also cut down the Antarctic pine forests, resulting in the depletion of mountain springs, flash floods on rainy days, and destruction of alpine livestock. The basis of the industry; the Spanish adopted a slash-and-burn method of setting fire to the mountains in order to provide better fertilizer for the coffee they planted, turning entire forests into ashes. As a result, the fertile soil was lost due to the forest. The protection was washed away by heavy rain, leaving only exposed rocks. The examples cited by Engels fully illustrate that only by respecting nature and acting in accordance with objective laws can people achieve the goal of transforming nature.