First of all, Browne brenner denied the view that children's intellectual development is predetermined by genes. In his book Human Development, he pointed out: "Social living conditions and education play a decisive role in the development of children in the first few years of their lives." Secondly, Hunter, a professor at the University of Illinois and former director of the National Early Childhood Education Laboratory, emphasized the role of environment and education in children's development in his book Intelligence and Experience written in 1960. His experiments prove that arranging all kinds of teaching AIDS around can induce and accelerate the development of babies and enrich children's life experience in advance. This is a remedy for children who grew up in uneducated families, so that mentally retarded children can be corrected. He concluded that infancy is a period to prevent the stagnation of psychological activities. It is considered that it is too late for children to re-educate at the age of four, and the earlier they have rich experience, the better. The third is Benjamin Bloom, who published The Stability and Change of Human Nature in 1964. He thinks that the speed of intellectual development is: 20% for one-year-old children, 50% for four-year-old children, 80% for eight-year-old children, and 92% for 12-year-old children. In other words, 3/4 of human intelligence is formed before entering primary school. Although there are many arguments on this issue, most developmental psychologists admit that the absolute level of intelligence develops at first, then slowly, and even has a downward trend in the final stage. This provides a psychological basis for the importance of early education. Many educators in the United States regard the above three viewpoints as an important theoretical basis for early education.