Do as the Romans do

I am currently taking a political course titled,"Classical Political Thought", and we have just started learning about the Roman Empire. The focus of the course is centered on the structure of the legal system the Romans used and how it affected the way they ran their empire comparative to the city of Athens. The most interesting structural aspect of Roman Law is in the way Roman's used to categorize the different kinds of law they used.

To begin with, Romans defined Law and Justice as "A constant and perpetual wish to render to each his due." The maxims of Law include: Live honorable, harm no one, and give to each what is due. With these stipulations for the premise of law, three categories were formed to separate the different types of law.

~The first is the Law of Nature, which is the only law that belongs to all animals of the earth. This is the union of males in females in matrimony and procreation.
~The second is the Civil Law, or the laws made by a people for themselves. This, then, is the jurisprudence as dictated by the Lawmakers of Rome.
~The last category is that of Law common to all peoples. These laws are the accepted rules for war, slavery, and property, by all of mankind.

The Roman Empire in all of its glory derived an entire legal system based on these three simple categories. This system lasted the Empire from 27 B.C.E -393 C.E.