Some individuals consider that obeying the same rules over the world is better than setting up separate rules for each country. One single legal system can allow fairness and comforts to humans, while it can lead to lose countries traditions and customs.
On the one hand, having the same rights can give an opportunity us to be equal with everyone who lives on the another edge of the world. When this legal system would set up in every country, each person can accept all the rules without disappointments. As an example, residents of one country may be able to purchase all their needs at the same price as residents of another country. Furthermore, traveling, working, living and studying can be easier. When all the population of the whole world have forced to obey a single legal system, they cannot cope with the difficulties of travels or other things, as they have to take an visa and interviews before flying around the world. Therefore, setting up the same rights over the world can be useful for both the equality of people and traveling and living without restrictions in any country.
On the other hand, in fact, each country have created their rules and human rights according to their history and local personality. When people have an obligation of obeying to one single legal system throughout the world, they may face some complications with losing their customs and traditional holidays. Because setting up single rights over the Earth means abandoning the traditions and ceremonies. For instance, all the countries have a lot of holidays during the year which promote their religion or history, like Christmas, Eid ul-Fitr, New Year or Easter. The population of all countries are not able to give up their holidays as the population have already adopted the rights that they have since they were children. Thus, tempting to have the same legal system can be profound insults about the derivitation of countries by leaving the rituals.
To sum up, despite negative sides of setting one rules throughout Earth, like the loss of history and traditional custos, it can lead to convenience and make easy to live, work and travel around the world.