Every human knowledge has also social consequences. When I say "A". I don´t say plainly "A is true". I say also that "because A is true because a set of my socially reputed fellows did something to affirm it, you must believe it, and, more important, I deserve a superior status than you, the reluctant.
As a consequence of this fact o human nature (which has a root in natural selection among collaborative beings). every corpus of accepted knowledge is associated from the beginning to a "church" of guardians of orthodoxy. No matter the intentions or the objectivity or how aseptic were the methods of the founders. There is a power to keep, much to gain and loose, and as time goes on, real truth becomes a secondary question. The creative, sincere founders are substituted by media debaters and mediocre defenders of the status quo.
In the same way, the common sense is an inner instinct, a product of biological and cultural evolution, that contains the inherited wisdom of the past in genes and memes that tell us inside what worked and what did not, in order to avoid reproducing the same errors again. What is "reasonable" for the Greek philosophers, like in common parlance, means what makes common sense. That is no longer the case today for the ruling elites and for most of the "educated" people today.
The liberal state was born as a consequence of the wars of religion among christian denominations, that ended up in a agreement of separation between church and state, where any non-consensual view was relegated to religion ,faith or ideology, and only the minimum common denominator was admitted as a foundation for politics. Part of this consensual body was the notion of "human rights" a concept extracted from the market contracts, which had rights and duties. Never before that concept existed. Before that, different persons had different rights and dignities. One can wonder why there was not a parallel concept of "human duties". More on that later.
This consensual political ideology was theist at the beginning (As is now in USA) later it was deist and now is materialist, following a path of progressive reduction of consensual ideological content, to accommodate the progressive secularization trough the entering in scene of new sects that were more and more secularists (which indeed was a logical consequence of the proliferation of faiths that the Reform gave birth and his inherent self-centered ideology of Protestantism that defy any kind of authority and ultimately and inexorably sanctifies the self will and the self desires. Wishful thinking becomes not a deviation but a criteria for truth and the french revolutionaries and the marxists were, in a deep sense, protestant sects).
In later stages, the consensual political ideology has demoted each country history, and even reversed it; Following its inexorable logic, the current political systems try to destroy national identity of each European country, in the effort to accommodate these new internal sects and also the former enemies that are entering in the countries via immigration. No matter how shocking is, this is the logical consequence of the spirit of the agreement that ended the religious wars of the XVII century.
In the theistic and deistic stages -that still can be seen, faintly, among anglo-saxon countries- the State made use of the Transcendence in one form or another for his legitimacy, since God has a plan revealed, and people believe in the divine, the legitimacy of the state, in the hearths of the people, becomes real when the nation-state is inserted in this divine plan and follow the divine commandments.
But when the consensual content is reduced to nothing but the self-interest of the majority by the majority rule, without any other authority that inspires neither the state neither any individual, then the society becomes a fight between individuals organized in groups of interests patronized by a political class of deculturalized, relativists individuals that have nothing, no plan, no meaning of life, no debt with past and future generations, no inherited wisdom to obey, except their will to power and their mythopoetic instincts extend the liberal miyhology to stay in power following the spirit of the end of the wars of religion.
These deculturalized individuals become the caste of rulers and administrators of the new regime under the ideology on tolerance with even more and more crazy offers of new individual and collective rights fabricated ex-nihilo against common sense. And of course in the name of peace among different sects (now called ideologies and religions).
That is the new centre-right- centre-left wing parties in Europe, that became the top caste system. However this caste system does nothing but to follow and extend what the first liberals did when they used the concept of market contract "right" for politics in the idea of "human rights". That contractualism, the basis of the liberal state establishes the state as a service right provider with a catalog of "services" and guaranties de facto. The caste system simply extend the services to the new clients to obtain the necessary majority rule. Socialism and multiculturalism is the logical consequence.
One would wonder why the duties that appears in any contract did not ended up in the creation of "human duties". But that is understandable since the modernity is essentially a revolt against duties, as is a revolt against God and common sense under the idea that the Heaven can be constructed on the Earth.