Zhou Lang told the Japanese mission that he was very concerned about the Japanese people and did not want war in Japan. He was willing to mediate between the shogunate and the daimyos, promote the concept of modern industry to Japan, and tell the Japanese that if Japan and China craftsmen produced products alone, they would be worth 100 Japanese craftsmen. If the Japanese do not learn these industrial techniques, Japan will continue to be poor, the poor will not have enough to eat, and the poor will not be able to support their children.

In order to solve the financial predicament of the Japanese shogunate, Zhou Lang expressed his willingness to provide assistance to the Japanese shogunate and give him a long-term interest-free loan, and told the Japanese shogunate that if Japan could not get rich by its own hard work, it would sooner or later fall into difficulties.

Malthusian theory has been introduced to Japan through China, and the Chinese have not directly translated the British writings, because the same truth has long been discovered in China, but not so systematically demonstrated by Malthus. Mathematics and logic are not introduced to analyze mathematics. It is simply to understand the truth that it is impossible to increase the population without limit, and put forward the concept of limiting population growth.

China has always been a country that attaches great importance to population, and since the Spring and Autumn Period and the Warring States Period have written records, all the princes and hundreds of schools have expressed their views on the population issue, but in the early days, everyone agreed that the monarch should devote himself to increasing the population, because at that time China was a large land, but a small population. Guan Zhong said, "If there is more land and the people are insufficient, the gentleman will be ashamed"; Mozi believed that land cultivated without a population had no value; Confucius advocated "the vast land and all the people"; The idea that "there are three unfilial pieties, and no queen is great" was put forward by Mencius.

Under these guiding ideologies, ancient China often adopted the family planning policy, which was of course different from the family planning of later generations, which was to limit the population, and was mainly to increase the population. Many dynasties, after the war subsided, in order to rapidly increase the population, adopted the government to punish late marriage, encourage early marriage, and even forced monks and nuns to return to lay marriages, and forced men and women who did not marry after the age of fourteen or fifteen. This is also the reason why the population of ancient China has always been larger than that of other contemporaries, because the government has established a management mechanism for population issues, although this mechanism does not seem to be so benevolent.

Since the Chinese population has long been insufficient relative to the country, the rulers have always regarded the people as an important political achievement.

However, there are also those who believe that people and the land should match each other, such as Shang Ying, who proposed, "If the land is narrow and the people are narrow, the people will prevail over the land; If the land is vast and the people are few, the land is better than the people." Wang Fu, a scholar in the Eastern Han Dynasty, proposed, "There are many people in the soil, and it is said that the wealth is a false land, and it can be attacked." The land is small and the people are not their people, but they can be exhausted. Therefore, the people of the land shall be commensurate."

It was after the Song Dynasty that there was a strong concern about overpopulation that really began to arise, and at this time, Chinese eloquence was really overwhelmed. Su Dongpo of the Song Dynasty proposed that there is no change in the land and the people are scattered, and there are often legacies and civil insufficiencies. But this is still a small-scale peasant mentality, advocating a policy of equal distribution of land. By the time of Xu Guangqi in the Ming Dynasty, it was still the idea of immigrating to the northwest to allow people to have land to cultivate.

In the Qing Dynasty, the population problem was more serious, and there were more scholars who were concerned about the population problem. In his political treatise "The Treatise on Peace," Hong Liangji proposed the phenomenon of excessively rapid population growth, "a fivefold increase thirty years ago, a tenfold increase sixty years ago, and a twenty-fold increase a hundred years ago," and "a threefold or five-fold increase in fields and houses." ”

This was the first theory that began to put forward that the excessively rapid population growth was the root cause of social problems, and that "the number of fields and houses is always insufficient, while the number of households and households is always in surplus", lamented that "the number of farmers is ten times that of the former and the fields are not increased, and the number of merchants is ten times that of the former and the goods are not increased", and "those who are diligent all the year round, and who are emperor all their lives and are self-sufficient, actually have the worry of ravines". Worried about the phenomenon of annexation, "one person occupies a house of 100 people, and one household occupies the land of 100 households, so it is no wonder that the ratio of those who died by wind and rain, frost and dew, cold, and turbulence is comparable!" ”

Compared with the ancient Chinese literati, Hong Liangji's political discourse has a common flaw, that is, the number is not strictly forbidden enough, he likes to use words such as 100,000,000, there is no digital comparison, and he only raises problems, and often does not propose solutions to problems.

After Hong Liangji, in 1814, Wang Shiduo, a scholar born in the Great Zhou Dynasty, was also concerned about these issues, and he proposed that "the power of heaven and earth is exhausted", expressing that China's land has been developed to the limit, but the population still continues to grow, "the number of people in the world has doubled in 30 years, so in the first year of Shunzhi (1644), there are 128 people so far (1855)". Worried about overpopulation, "people floating on the ground are several times", "more people are poor, and not enough land to support".

His theories are still not higher than Hong Liangji's, but he has proposed solutions. Wang Shiduo is a strange guy, his theory is very special, the solution to overpopulation is very ruthless, and the government should adopt forced infant drowning, "those who are not in good shape, unbeautiful in appearance, and poor in eyebrow will be drowned." The system of marriage and childbirth has been strictly enforced, and policies such as "strictly prohibiting men from marrying under the age of 25 and women under the age of 20" and "marrying at 30 and marrying at 25" have been adopted. Restricting childbirth, proposing "extensive prescription for non-fertility", so that women who have given birth to a child are prohibited from having children, and "women take cold medicine and take it after giving birth to a child". For those who violate the regulations, "the violator will be killed"!

These theories were used by the political forces represented by Zhou Lang to spread a sense of crisis that China's land was at the end of its power and that the land was no longer enough to feed the people, with the aim of finding a theoretical basis for joining the world war. Tell the people of the country that they are fighting for land for their children and grandchildren, and if they don't fight today, they will starve to death tomorrow, and if they don't fight today, their descendants will starve to death.

Wang Shiduo also had the idea of valuing business, but he still looked at business problems from the highest perspective, and he found that Huizhou merchants did business abroad all the year round, and the population in the areas where Huizhou merchants lived in southern Anhui was small, and their families were wealthy. Advocating the idea that governing the people requires the people to be rich, so business is encouraged while population growth is restricted.

Because Wang Shiduo's ideas were too much in line with the needs of the rulers, he was promoted in this history, and he was also successful in this era, and then he entered the official school to study, and then entered the household department as an official, and received funding from the upper echelons to conduct his research.

He is naturally different from him in history, more logical, educated in mathematics, and knows how to use numbers to argue.

Moreover, he was able to conveniently consult the materials of the past dynasties for research, and the phenomenon of the doubling of the population in 30 years was first discovered by Xu Guangqi of the Ming Dynasty, based on the figures of the Ming Dynasty's clan population, and the clan population registration was very detailed, so it was more revealing. Wang Shiduo also consulted the population data of the Manchu period, and he found a strange phenomenon, that is, after Qianlong, the marriage age of the Manchu clan population began to be delayed.

The age of marriage for women in the Qing clan was raised from fifteen or sixteen to their twenties, and the proportion of celibacy began to increase significantly. The rate of concubinage among men in the clan has dropped dramatically, as has the fertility rate of each of their wives and concubines, as well as the fertility rate of each family. Not only that, but the mortality rate of newborn babies in the clan is also changing. In the late Qianlong period, the mortality rate of female babies in the late Qianlong clan was as high as 1/3 within one month of birth, which was higher than that of poor Liaoning banner peasant households.

Wang Shiduo conducted an in-depth excavation and study of this strange phenomenon, by comparing the notes of the literati at that time, and even directly visiting those who had experienced the longevity of the late Qianlong period, he determined that the Manchu clan women would marry later or even be celibate, and men would reduce their concubines, and the reason for the increase in the death of female babies was that the subsidies for the children of the clan in the late Qianlong period decreased, so women may not be able to marry because they could not get a dowry, and men would reduce their concubines and have fewer children because they could not afford it.

But no matter how poor the Qing Dynasty clan was, it was much richer than the ordinary people, why did the people have a large number of children, but the clan could not afford it? Wang Shiduo believes that the clan lives in the city, and the people in the city are easy to compare, and the consumption is high, and the more money is used for consumption, the less money is spent on raising offspring.

Based on this, he put forward a number of arguments, that the imperial court should encourage peasants to move to the cities, and that luxury consumption should be encouraged. In this way, the population can be effectively reduced. All of his discoveries were fueled by interest groups, and they were quickly popularized through newspapers, books, and other situations. It became the reason for the army to wage war, and it became the basis for the industrial groups to attract the peasants to the cities.

It can also be used to fool the Japanese and tell them that encouraging their own country to consume Chinese products can reduce the Japanese population. And Japan is also a country that has been plagued by overpopulation for a long time, even more serious than China, so serious that not only civilians, but even some samurai class, have a tradition of drowning babies, not drowning female babies, but even male babies drowning directly.

A large number of lower-class samurai went bankrupt and joined the rebel ranks.

The same theory of Wang Shiduo was used to persuade or threaten the Japanese, he said that "the merchants are clever but incompetent, the peasants and workers are stupid and ruthless, and they can unite their hearts for chaos", telling the Japanese that commercial trade should be encouraged, and that merchants will not rebel, and that peasants and workers will rebel together.

It is not known whether the Japanese accepted this set of statements, but they sold the Chinese emperor a face, and the war between the shogunate and the daimyo of the shogunate faction did not break out. Rather, it is a slow and difficult industrialization process. Japan's second advantageous industry began to take shape, and it was ocean trade.

Japan is an island country, and it should naturally be a maritime civilization country, but it is a pity that Chinese culture is too strong, which directly reverses the island civilization of Japan into a typical agricultural civilization.

Needless to say, the Tokugawa shogunate, fearing that the Japanese would cause an attack from China, stepped up its efforts to crack down on the Japanese at home, closed the country to the sea, and forbade its citizens to go to sea. But it is impossible for the Japanese not to fish, on the contrary, Japan has a stronger fishing tradition than China. While most Chinese fishermen work inshore, the Japanese have a tradition of hunting whales.

The Japanese discovered that trade could be profitable, and under the shock, influence and drive of China, a large number of Japanese stepped into the farther ocean.