This is a famous assertion put forward by helvetius, a French materialist philosopher in the18th century. Holbach also holds the same view. The implication of this proposition is that people's morality and intelligence are not born, but are determined by acquired environment and education. This proposition is an inevitable logical conclusion drawn from a series of philosophical views of helvetius and others on human nature, human spirit and ideological source. They believe that people have an eternal natural nature, that is, self-love (selfishness, self-interest), and from the perspective of sensory theory or from the perspective that people are a special form of material existence, they all have their constant laws of activity. They believe that this natural nature itself does not care about good and evil, and the reason why this self-love nature tends to be good and evil morally lies in the social environment. The social environment they refer to generally refers to a wide range of aspects that people have contacted in their life experiences, but mainly refers to the social, political and legal system that has a great influence on the formation of people's spiritual and moral values. In their view, people's moral motives and purposes are inseparable from people's interests. As long as a virtue is encouraged and rewarded, citizens will follow the desire to pursue personal happiness and tend to virtue and kindness. A good political and legal system adapts to human nature, rewards good and punishes evil, so they make people do good. It will make people evil. They also use the concept of education widely, which refers to both the influence of political and legal system on people and the role of school education. From the materialistic point of view that intelligence is acquired, helvetius thinks that the difference of human intelligence is the result of different education, while Holbach thinks that the difference of human body structure is also the reason for the difference of intelligence between people, so there are some differences between them on this issue. The idea expressed in this proposition not only provided a theoretical basis for the bourgeoisie to oppose feudal autocracy at that time, but also had certain theoretical value. Their understanding of the environment and the relationship between man and the environment has not yet reached dialectical materialism.