Gao Erdun took the lead in studying individual differences, and Gao Erdun emphasized that heredity was the cause of individual differences. The quantification of psychological research began in Gao Erdun. He invented many sensory and exercise tests, and expressed the difference of psychological characteristics by quantity. He believes that all human characteristics, whether material or spiritual, can be quantitatively described in the end, which is a necessary condition for realizing human science. Therefore, firstly, the statistical method is used to process the data of psychological research, emphasizing the average value of the data and the difference between high school and high school.
Gao Erdun was not a psychologist, but he had a great influence on the early development of psychology. 1850, he explored southwest Africa and won an outstanding achievement award. 1853 and 1856 were elected as members of the Royal Geographical Society twice. He was knighted in his later years.
Gao Erdun's major works in psychology include: Genetic Genius (1869), British Scientists: Their Endowment and Cultivation (1874), Research on Human Talent and Its Development (1883) and Natural Inheritance (1874).
Gao Erdun's contribution to psychology can be summarized in three aspects: undifferentiated psychology, quantification of psychological measurement and experimental psychology. In the anthropometric laboratory of south kensington Museum in London, he used instruments for anthropometry and psychometry. The measurement items include height, weight, vital capacity, tension and grip strength, slapping speed, hearing, vision, color vision and so on. In order to study individual differences in ability. The individual differences of images are also studied by question and answer. Let the subjects determine one thing first, such as the scene of breakfast, and then they recall the image of the object on the table, that is, the clarity and certainty of food. After sorting out the answers, he found that there are great individual differences in the images of the subjects: some people mainly use muscle movement images, some people mainly use auditory images, and some people mainly use visual images.
He emphasized that heredity is the cause of individual differences. He demonstrated the relationship between genetic factors and individual differences through genealogical investigation. He was the first person to put forward the proposition of general ability and special ability clearly. He investigated the genealogy of 977 British prime ministers, generals, writers and scientists in 1768- 1868, and found that there were 89 fathers, 29 sons and 1 14 sons. Among ordinary people, 4,000 talents produce an outstanding person. Therefore, it is asserted that "ordinary ability" is hereditary. When investigating 30 families with artistic ability, he found that 64% children in these families also have artistic ability; In 150 families without artistic ability, only 2 1% daughters have artistic ability, so it is asserted that artistic ability-"special ability" is also inherited. He found that with the decrease of genetic relationship, the proportion of excellent relatives also decreased significantly. He also used the data of 80 pairs of twins to prove that people's psychology is completely inherited through the fact that twins are more similar than other brothers and sisters in psychological characteristics. This also made him the first to notice the importance of the methodology of identical twins and fraternal twins in estimating the relative role of genetic and environmental factors in human variation. According to the relationship between heredity and individual differences, Gao Erdun advocated choosing a good spouse and improving race, and in 1883, he initiated the word "eugenics" in the book "Research on Human Talent and its Development". 1883, Gao Erdun published Research on Human Talent and Its Development, which summarized two extremely important research methods and achievements in experimental psychology. The first experiment was about free association: he wrote a word on 75 pieces of paper in advance, and only asked the subjects to read one piece of paper at a time, then measured the time required for two impromptu associations with an accurate timer, and then analyzed the possible origins of these associations in the subjects' experiences. He found that the most frequent associations often came from distant childhood. In this experiment, he also confirmed that human beings have the ability to associate with a certain shape when they see or hear a certain number, which he called "number shape". The second is the extensive investigation of psychological images: he asked the subjects to think of something first, then pay attention to their "psychological vision" pictures as much as possible, and answer a series of questions such as brightness, clarity and color, and score according to their intensity. It is worth mentioning that in these studies, he introduced questionnaires and scoring methods into psychology for the first time. His contribution to experimental psychology also includes a series of psychological testing instruments and methods he invented. Some instruments were later named after him, such as Gao Erdun flute for measuring hearing threshold and Gao Erdun stick for measuring visual range, which were standard instruments in psychology laboratories until 1930s. He also used bottles filled with different substances to test his sense of smell, which has been used by later generations to this day. In addition, he also designed instruments and methods to measure muscle sensation, reaction and touch.
Although Gao Erdun was not born in psychology, it is generally believed that his influence on the early development of psychology is greater and more profound than that of any psychologist in the same period. Because of his great achievements in many fields, he has been recognized by the world and won many awards and honors. He was knighted in 1909.