Groups of people who live in a nation had to follow a set of regulations that created by their ruling government with clear border that separate one nation with the other.
In the earlier period, these groups might gather with different culture and language. After interacting together for a long period of time, assimilation will occurs and they start to use same language and develop a unique culture that does not exist in other nations.
A scientific law is the simple mathematical expression of the relationship involved. A principle is the same relationship expressed in words. A theory is the explanation of the facts that make up the relationship.
