They have developed their system utilising timeless principles of human interaction which, over the millennia, have been discovered and codified. These fundamental, common-sense principles underlie every form of law extant on the planet. Every legal issue and dispute deals with one or more of these principles. Since all human interchange is commerce, in order to rule people it is necessary only to govern the commerce by which they interact and subsist. In commerce truth is sovereign.
Truth is expressed in the form of an affidavit.
An unrebutted claim, charge, or affidavit stands as the truth in commerce. An unrebutted affidavit becomes the judgement in commerce. All matters must be expressed to be resolved. He who leaves the field of battle first loses by default. The reason, this scenario prevails is because the world has been set up to run precisely this way.