Politics might have its origin in dispute resolution, as a tribal leaders took on the responsibility to resolve disputes within their tribes. The chief or dominant member of the tribe or clan acquired the power to resolve disputes, and his decisions were collectively binding. One example that comes to mind is that of Solomon resolving the dispute between two mothers by suggesting that they “cut the baby in half.” Thus, power is the symbolic medium of politics, and it’s expressed in collectively binding decisions.
In the 13th century, the Magna Carta created boundaries between the English monarchy, the nobility, the law, and the Church. The document bound the king to the law and protected the Church and the nobility from the whims of king. In 1648, the Treaties of Westphalia established new legal boundaries between nations, kingdoms, religious sects, etc., thus ending the Thirty Years War.
The treaty gave the Swiss independence of Austria and the Netherlands independence of Spain. The German principalities secured their autonomy. Sweden gained territory and a payment in cash, Brandenburg and Bavaria made gains too, and France acquired most of Alsace-Lorraine. The prospect of a Roman Catholic reconquest of Europe vanished forever. Protestantism was in the world to stay.https://www.historytoday.com/archive/months-past/treaty-westphalia
As for modern society, the function of the political system is to prevent other function systems from converging. Politics uses the symbolic communication medium of power to maintain separation between different, autonomous systems. This communication takes the form of collectively binding decisions. The political system, according to Luhmannian theory, applies power to enforce decisions in questions which cannot be resolved within any other subsystem of society (e.g., the economy, mass media, education, science, art, medicine, religion) and which may cause general social instability. As King and Thornhill write,
[The] political system is the function system of modern society which provides power as a universal resource. It is, therefore, the system which enforces decisions in questions whose implications extend beyond the boundaries of one or another system, and which then create problematic couplings between distinct systems.
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For example, if an investment policy begins to have disastrous consequences for the health of the inhabitants of a particular region, or if medical treatment has serious financial implications, the political system might attempt to resolve the issue by means of a collectively binding decision concerning the relation between the two systems concerned. A further situation where politics may perceive the need for collectively binding decisions is that of a crisis which threatens to damage other systems, including politics itself. . . . The application of power thus has its most specific function in the avoidance or obviation of unnecessary structural coupling.King and Thornhill (2015, 70-71).
Politics, then, can prevent discreet function systems from collapsing into one another, thus preventing social instability. Politics can tell the difference between function systems. This is what it uniquely equipped to do. The economic system cannot observe differences between the political system and the law, for instance. Only politics can observe these differences. So politics has to observe and maintain these differences, including the the difference between itself and the other systems.
A well functioning political system allows society to function with a minimum of uncertainty or chaos produced by converging function systems. For instance, the political system learned that when religion and science come together, as in medieval disputes over the Copernican revolution, society gets destabilized as various unintended consequences result. Politics then has to step in and separate religion and science.
When their system boundaries are maintained, the economy, the law, the education system, the mass media system, science, and other function systems are able to carry out their operations without expending excess energy restabilizing themselves. They are able to main dynamic stability. It is a dynamic stability because all systems must stabilize and restabilize themselves amid a complex, ever-changing environment.
The political system establishes itself by linking one collectively binding decision to another. Each decision has to account for the system memory, which is all the past decisions. There are precedents just as in law. This is self-referential communication. The system communicated with itself.