From nesting to houses built by the Yellow Emperor, human beings gradually formed a home. In ancient times, the big family composed of kissing, respect and similar relations was the embryonic form of the country, while the home in modern society was the basic living unit of the country. The functions and functions of the family are very different from those in ancient times, and all these are magically formed naturally. Only when you have a family can you have a couple, and only when you have a couple can you get married. According to ancient records, there have been generations of couples in the Sui Dynasty, and Fuxi began to ask for marriage. As for the function and significance of marriage, the Book of Rites makes it very clear that it is good to combine the two surnames, which can be used to worship ancestors and carry on the family line. In ancient China, ancestor worship was the most important social activity, similar to religion. Therefore, the role of marriage is to sacrifice ancestors and carry on the family line. Modern society is different. Because of the freedom of marriage and other factors, at least it has more functions of combining love and educating children.

As we know, monogamous marriage system is determined by law in many countries in the world (including China), which is a very strange phenomenon, because most human society has consciously observed this habit since ancient times. It can be said that this system can still be well implemented in most human beings without legal constraints, which shows that monogamy is a naturally formed habit, and the law has lagged behind in formulating this system in order to emphasize democracy and equality. So why do humans? Let me briefly explain this problem from the following aspects:

1. Humans and animals have evolved in different directions. There is a Fisher's Law in the West, which is basically proved, meaning that the sex ratio of all mammals (including humans) is one to one, and the proportion of males possessing females and having mating rights is determined by the weight ratio of males and females. As a result, it is estimated that the ratio of human beings is one to three, that is to say, a strong man must have three women to meet the natural selection rule that excellent genes can be inherited. But in fact, humans don't follow this rule because we need to evolve in a different direction from animals. Man can become the master of the earth by wisdom and unparalleled great social cooperation. Monogamy makes human beings have extremely diverse and different combinations, and these different combinations have produced all kinds of complex and different people, which will be beneficial to our development in many aspects. The difference between human body and intelligence is much greater than that of other mammals, and it is these differences that make each of us have different wisdom and different skills. The combination of these differences has enabled us to produce various great, splendid and rich civilizations. The combination of one to three can only make our descendants stronger and meaningless. Barbarian warfare is very powerful. However, their ability to transform the world is limited. Therefore, we humans still have not escaped the law of natural selection, but have chosen an evolutionary direction different from other animals. The evolution of our bodies is manifested in the increase in the proportion of our heads. Some people may retort that our modern people's physical evolution has been highly developed. I don't think this is contradictory, which shows that human beings want to evolve to a higher level. In order to expand their living space, human beings should not only be masters of the earth.

Second, monogamy is more conducive to the health of future generations from a genetic point of view. With the decoding of the genetic code, we know that the genes of the next generation of children account for half of their parents. If polygamy or polyandry is practiced, such a family will certainly have more offspring than monogamy. Then, in the marriage after several generations, the possibility and probability of newly married couples having duplicate genes will increase (that is, the possibility of closer blood relationship will increase)

Third, better cultivate future generations and force human beings to practice monogamy. Humans are the slowest growing process of all mammals after birth, which is somewhat similar to birds. 95% of birds are monogamous because they can live independently for a long time when they grow up. Only when their wings are hard and they can fly can they be cultivated at the same time, which will improve the survival rate. Our human growth process is more complicated. Including the body and brain have completely stopped developing for more than 18 years. At the same time, the vast majority of mankind has got rid of the natural economic state. If they need to fully adapt to the survival in the socio-economic environment, their parents will have to make more efforts. Therefore, monogamy conforms to both human biological characteristics and social characteristics. Two people's energy is put into their offspring at the same time, which is beneficial to their growth and education.

Fourthly, the stability and balance of human society (or population) need monogamy more. The reason is very simple. Take a tribal group as an example. If monogamy is not practiced, at least half of the people have no wives or husbands, and these people are fighting for the right to be husband and wife. Undoubtedly, it is the most unstable factor, which will lead to endless struggle. In order to be stable and conform to the law of balance, monogamy is definitely the best and most effective way, otherwise bloodshed happens from time to time, which is a great threat to the development and survival of the tribe. Even the most primitive tribal leaders should be able to see this problem clearly, let alone people in modern civilized society.

5. The above mainly expounds the necessity of monogamy from the biological point of view of human beings, that is to say, the natural laws of biology force human beings to practice monogamy, so monogamy is more reasonable from the social point of view. First of all, from the perspective of social possibility, since human society entered the farming era, agricultural civilization and technology have made great progress, making monogamy fully capable of raising the next generation independently in the family. In the industrial civilized society, this ability has been strengthened, but in the primitive society of promiscuous marriage, it is often that several mothers raise one child (note: actually this is not contradictory to the third point, and it is more beneficial for both parents to raise themselves when they are young), and after entering the civilized society, the existence of monogamy has matured.

6. From an economic point of view, monogamy conforms to the principle of the highest economic efficiency. The reason is very simple. As the most basic living unit of society, the family is monogamous with the same structure, which will give full play to the advantages of each member of the family and provide more convenient conditions for the economic activities of the whole mankind. Take the logistics work of the army as an example. The more consistent the logistics support of all soldiers in terms of food, clothing, housing and transportation, the simpler their logistics work will be. The more orderly, the higher the efficiency, and vice versa. Another example is family housing. The more each family has the same structure (for example, a family of four), the more convenient it is to build a house with the same standard, and the efficiency is of course high.

Seven, from the perspective of the inevitable progress of human civilization, monogamy is the system that can best adapt to the pace of civilization development in advance. This truth is not complicated. Democracy and freedom are the goals pursued by mankind. Historical facts also prove this point. All men are created equal. If monogamy is not practiced, more than half of people will lose their most basic marriage rights. What is equality? Therefore, a country that truly enters a civilized society is truly in line with a civilized society.

To sum up, monogamy is the product of nature and civilization, but this system or habit is divorced from the contradiction between human beings and animals, which will inevitably intensify new contradictions, such as extramarital affairs and the appearance of prostitutes. These are all instinctive actions of human beings, which also shows that marriage and love are essentially different. The function of marriage is more social, while love is more biological and independent. Abolishing monogamy will never solve these new contradictions. We should acknowledge the inevitability of these new contradictions, and the solution is simple. In short, we must rely on sober understanding and rational restraint.