Laws should be flexible enough to take account of various circumstances, times, and places.

Laws are the key institution in modern society, and without laws in a nation, it must be in the situations of conflict, turbulence, and even extreme anarchy, leading to the high cost of the government. Convinced of the important of laws, today's countries have basically implemented this kind of laws and that, which may be imperfect but to some extent adjust various sorts of contradiction among people. Meanwhile, it is difficult for law-makers to let laws flexible enough to any circumstance, time, and place, though laws have the cycles of amendment so extensively and carefully according to the development of a society.

Indeed, laws have been evolving with the revolution of a society in order to ensure social development and stability. It is well-known that the circumstances, times, and places to which laws are applied have changed from past to now, so if laws were not flexible, there would be no legal basis for people to follow and criminal activities would be filled in the society. Take Chinese marriage law as an example, in the old China the marriage was pre-arrangement, no freedom, polygamy, while in modern times, with the increasing education and more independent economy, people pursue for marriage of equality, self-choosing, and monogamy, so the old marriage law was replaced by modern marriage one. Moreover, a lot of new things emerged based on internet, extremely changing the environment, time, and place of criminal activities. There are a wide range of crimes produce: internet fraud, internet trafficking, cyber warfare, cyber terrorism, and the like. For this reason, new laws based on internet crimes must be enacted, or social order would be hard to keep peace. Laws are also subject to the same order as any other living thing: production, development, abolition, with the passing of time.

However, it is unrealizable for laws to be flexible enough to adapt to any circumstance, time, and place. This lies in two reasons. One is the time and cost of law-making, because the formation of any law is not overnight, often taking long time to such process as sponsoring, discussing, passing, and publishing bills. Another is that encompassing laws are beyond human ability, because things are always in the dynamic state.

Conversely, back to the law history, there are many laws that keep constant, because the relative stable laws are beneficial to social development and stability, as well as the habit of people's law-abiding. If laws are often made this sort of amendment and that, it will gradually decrease people's enthusiasm for abiding by laws, and will make them bewildered when they are faced with numerous and complicated laws. For instance, the U.S. Constitution, aiming to defend civil basic rights of life, freedom, pursuit for well-being, has long been the fundamental principle of America for hundreds of years though the world has changed greatly, which promotes American development as the biggest economy in the globe all the time.

Last but not least, the stable laws to some extent ensure the welfare of all the citizens and the nation. For one thing, the constancy of some laws guarantees the alternation of authority in this way that the laws will not change with the will of the authorities, who must strictly conform to all kinds of laws in their nation. For another, it contributes to the maintenance of the public right and benefit.

All in all, the goal of laws is to keep the society in order and the interests of all the people, the laws thus should be adjusted to match with the development and requirement of society. But overly flexible laws will be the opposite for its aim.