In our present marriage, it is impossible to marry one's own close relatives, and the marriage law clearly stipulates that close relatives can't come together, because the marriage of close relatives will have a great probability of making the baby suffer from family hereditary diseases. In ancient times, there were often examples of cousins getting married, but their children were relatively healthy. It is because polygamy in ancient times made the inheritance of blood impure, and cousins were different from cousins, so cousins were not close relatives.

First, close relatives cannot get married. The law of our country clearly stipulates that consanguineous marriage is not allowed, but in people's cognition, consanguineous marriage is simply against the ethical code and will not come to any good end. From the perspective of biological evolution, consanguineous marriage may also bring very serious diseases to children, so from the perspective of science, close relatives cannot get married. From a moral point of view, Confucianism will never allow the corruption of consanguineous marriage.

Second, cousins in some ancient TV dramas, cousins often get married and their children are healthy, which makes many viewers in front of the TV feel very confused. Didn't you say that close relatives can't get married? Why can cousins be together and give birth to healthy children? In fact, cousins are different from cousins, and cousins are not close relatives in the strict sense, because they belong to two blood lines after all, which are different from cousins.

Third, polygamy is another reason why brothers can get married in ancient times, which stems from the marriage system at that time. Marriage was polygamous at that time. A man can have many women, a formal wife and many concubines, so he will have many children, whose pedigree is not particularly pure. Therefore, even if cousins get married, there will be no children who are not sound because of blood.