Heredity means that a specific status or title (e.g. official rank, peerage) held by a parent or their occupation or the like is passed on to their children, family members or in-laws, thus ensuring that such successors obtain social power and authority. When a title, a court rank or position is passed down through a family, this is called Shui; heredity of the family name or the like is known as Shumei.
In the ancient world, with regard to the status of an Emperor of the Roman Empire the legitimacy of authority was maintained by a successor keeping up the appearance of continuity by becoming the adopted child of the last Emperor; on rare occasions a blood relative succeeded by representation. The Roman Empire was rather exceptional; often in other regions, empires and kingdoms of the ancient and medieval world the status of an emperor, king, aristocrat, administrative official, or knight was strictly passed on through a blood line. Such a fixed lineage of a monarch is called a dynasty.
This custom resulted in a distinct differentiation between the class of rulers and those who were ruled, their subjects. In Japan, the Constitution of the Empire of Japan stipulated the heredity of the Imperial throne of the Imperial family (unbroken line), and the heredity of a person's social status such as member of the peerage, warrior class or commoner; the only way to overcome this system of differentiation was through marriage and claiming a connection by blood line. The Constitution of Japan stipulates that the position of the Emperor is hereditary.
It is common practice for children to inherit the trade or family business of their parents. For example, children of a pharmacy owner or medical practitioner will aim to enter a school of medicine, dentistry or pharmaceutical sciences in order to take over the clinic or pharmacy run by their parents, and if a biological child is not able to take over, then often an adopted child will become the successor.
Even though it is not an independent enterprise, to take the same occupation as the parent is advantageous in terms of the succession of intangible assets such as goodwill, personal networks and the knowledge required in the course of their work; therefore, many of those occupations or positions that are regarded as socially outstanding such as politicians, diplomatic officials, academics, and entertainers tend to be passed on through the generations. Particularly with regard to the traditional performance arts, court nobles and the founders of a particular style of performing art (philosophy) would pass on the knowledge and skills of their tradition to their descendants; this would result in a kind of family business and even today heredity is commonly found in Kabuki, Noh drama, Kyogen (farce played during a Noh play cycle), swordsmanship, martial arts, Japanese archery and manners.
It is also common that the CEO of a large enterprise will pass on their business to their children or family members or in-laws; however, this can be considered an extreme example of nepotism, and some commentators have criticized this practice (e.g. Makoto SATAKA). In addition, it is pointed out that before the privatization of the postal service, the appointment of the master of a special locally-owned post office was an example of virtual heredity.
Heredity often also applies to such occupations as prison officers and executioners, as seen in social problems found among prison officers or the summary of executioners. In many countries an executioner was victimized by society and strongly discriminated against in terms of jobs or marriage; therefore the role of executioner was usually limited to a specific social group or clan, and it is said that this is a reason for normalizing heredity.