The skeptic does not belong to any specific ideology, but we can consider him is person who question context in their time. Evolution of though had many context, but underline about the skeptic is will have impact behind the place and time.
History shows for example the monotheistic ideas may haven part of human experience from the beginning. The rebel Pharaoh Akhenaten the then king of the 18th Dynasty (1369-1332 BCE), he was consider as outcast. Akhenaten rein was in the high points of Egypt. Pharaoh Family place was in Thebes, the city of God Amun.
The absolute power of the Pharaohs change the cults of Egypt to the Worship of Aten, solar disc-Akhenaten regime consisted 16 years. He closed the temples Amun and sent the priest of Amun to destroy the statues of Amun. After his death the Amun priest make sure, his legacy was to be forgotten, but his influence to a single God, had effect in the region from the fact his position.
Another significant figure rebellious and skeptic in the particle society was Socrates. Socrates rebellion questioning the Democracy of Athens, where Athens was a society driven by slaves and the Democratic Athens was privilege to few free males. The ideal state of Socrates was described by Plato in the Republic. Socrates ideal was just not radical Aristocrat, but Socrates philosophy king created the Emperor, Caesar and the dictatorships. The believed of absolute power to benefit the many, just because the philosopher king had the access to knowledge to make the judgment.
After Constantine made Christianity the official religion, in 529 CE Christian Roman Emperor Justinian order the close of the Academy, to that time many Romans like Cicero and Horace were educated in this Schools in Athens.
Zeno of Citium founded the Stoic school. The school idea of self control and the opposite Epicureanism who believe in atomic materials and the materialism question of the divinity intervention, Epicureanism philosophy consider small pleasure to obtain tranquility. The significant of the two schools is the religion does not define away of life. The beneficiary of Authoritarian single power was the church and divine right of the Christian Emperor. In the city of God, Augustine not just deal with his own pagan roots, but set ideal in some many ways the Socrates vision, where the absolute Authority of the Church and vision of the Church.
Skeptic is not a tradition on the West, but in East Buddha philosophy was a rebellion towards India cast, yes, there is spiritual guide, but in some ways to find a truth was social commentary. Confucius philosophy of order appears after the bloody unification of China under Qin Shi Huang.
Islam skepticism has different trajectory, the school of rationalist Avicenna (980-1037), Averroes (1126-1198) and Ibn Khaldoun (1332-1406). They try to come with terms of the inherent Materialism of the Greeks with the new religion of Islam. Even in the long run could not make head ways with their program. A key for development for society is an open society, not just ideas, but social and political.
China had 300 plus ships, under command of Zheng He, which open China, but in the 1433 the exploration was stop by the Ming dynasty and close China. Japan open partial to west, since survival of Feudal system was the access to technology, but technology is one aspect, since to created needs interactions in many levels: Sciences, Philosophy, Art, Music, Literature are part of human experiences only can be explorer in open society any type of repression will stifle.
For Christianity the church to maintain power of knowledge, by limiting access to the books, since only the elite had education Latin, Greek and very few knew Hebrew, that limited who own the knowledge. Before Luther reformation, the crusades remained Europe to world outside and Latin Kingdom of Jerusalem (1099-1291) come in direct contact with outside world and not since Mongols Europe had not access to trade routes of silk and spice (Marco Polo). To date the feudal system were land defines power, but the cities since Rome had not significance.
Kevin Carson have a great analytical analysis for British Island dealing to the access and distribution of lands after William conquest, were limiting the common land and many cases the common land was lost. Even, when ownership of the land was not in question the owners had to pay taxes to the new land owner class.
Of course, economic power by the cities and the nobility limiting the access to the land to the serfs create economic discontent. The call of Urban II for the crusades had not only religious value but had also an economic connection pressure relieve. The Jews since they hold to their own believe and value, were consider outsiders. The church and nobility demanded a social homogeneity and created an idea of collective value, where the Jews become a challenge to Augustine Utopia of City of God, so in some ways the economic value was given to the Jews. Since 325 CE, Jews were not allot to own slaves especially Christians slaves, since in Jews tradition the slave in house hold they are to become Jews in case the slaves are free, they are full members of the Jews community Christianity limited the access to cheap labor. An aspect of Rome economy was slaves, the free labor provide by the slaves could not be mach by pay labor and pretty much the condition who can own land become limited to Christians, and not just any Christians but nobility, and limitation to trades via guilds, put the Jews with limited access to survive.
For Christianity the translation of bible into vernacular, was a direct challenge to the Church, but for the Church heretic was a conflict since authority has been form in the Church Cannon challenge by Gnostics Gospels suppressed. The Cathars or Albigensias, and Waldensian was the beginning to challenge the absolute and corrupt power of the Church, the fact in another hand Spain conquest by Islam and the hold power for 800 years, created a exchanges of ideas an Open Society, but that Utopia ended by Islam own radicalism and recon quest.
The reformation was possible because the brought God to individual level were the bible was not in domain of elite being the Church or nobility. The cost of such enterprise not just translation, but to call for such enterprise burn many, like John Wyclif (1330-1384), who protest against Augustine skepticism, but he demanded the Authority was directly form the Bible and early Church. He demand use secular Authority to control the Church authority and question the authority of the pope. Another significant figure is Jan Huss (1372/73-1415) a Philosopher and Master in Charles University in Prague. The context of question the Authority of the Church was in 1408, when there was claim and contra claim, between the French Pope Avignon Pope and Pope Gregory XII and Huss call was the vernacular Bible, he was burn at the stake.
Luther and reformation in England, but from a secular knowledge Galileo for the first time had a method which was not theology, but Empirical where the Church Authority, but the nobility divine right was put into test. Galileo did not invite the empirical method, but Galileo was a child like many of Roger Bacon (1214-1294), who emphasis was empiricism. Galileo with telescope and moreover Galileo brings Copernicus ideas into a tangible view where the base of God was to be put into empirical church and the church reaction create their own demises of their authority, by creating Galileo ideas dissenter, like many ideas of dissenters they have appeal of the forbidden.
Erasmus of Rotterdam (1466-1536) facilitated the introduction of Humanism into discourse of Authority, and they beginning of secularization of the knowledge.
The tolerance of Benedict Spinoza, is in part of being decedent of the Jews being through out from Spain, and the second expulsion of his own roots. Spinoza being the minority of the minority felt just to exists was not enough to coexist but tolerance, the same view was taken by Montaigne, besides the creation of the use of the essay, where he question the religious conflicts of his time.
Luther was a reformer, but he was also a reactionary. Luther supported the nobility against peasants of the Alsace, and the peasants appeal to Luther was to not abele, his cruelty against who question the feudal order when to Jews diet in Worms Germany, and the expulsion of the Jews in Saxony. Luther, in “On the Jews and their Lies” a 60,000 thousand words of venom was not just the fact Jews challenge the Christian Messiah, but Luther sensibility sense of order.
Anti-Semitism was not unique to Luther, and the source was Roman Catholicism which needs Jews is justification to the authoritarian power of the Church. For the Church was not only about the Messiah rejection, but the order where everyone had place in society, the consequences, when Church power had not value, but the sense order continue. Austria in the 1930’s had Roman Catholic dictatorship, the same Croatia and Slovakia. Hitler use the Anti-Semitic symbols layout by the Roman Catholic Church, in many respects Hitler believe the Unification of German speaking people will be done Catholics, Hitler create the secular Anti-Semitic with the roots in Christianity.
Significant the skeptic using empiricism is a tool, Darwin evolution is a master piece in empirical exercises and skepticism, but from Pharaoh Akhenaten to Darwin the Human experience when from something outside ourselves to something is about ourselves.
Besides of human though, the experience transfer to other spheres, political sphere, where the divine right of Aristocrats was question in Enlighten, the America Revolution with contradictions, where the right of the white to have a continental nation, in expenses of the Natives, and use of race for perpetual cheap labor of African Americas, but nothing come into conflict to the industrial revolution, where masses of serf become working class, the power of land transfer to production.
The question of skeptic was about the control, political power, where Capitalism taken root of the order in the Aristocrats. New Utopias define by Thomas Moore, where ideal was to achieve the Feudal order.
Marx using Hegel Christian philosophy was the Philosopher king was the working class and the class eventually through class consciousness will achieve the ideal of the Feudal Order, but to speak to consequences of such new order. The Critics following another tradition, whether was William Godwin say man is rational eventually the irrationality of a single power, government will hamper individual rationality. Later on Proudhon a society without a central Authority, the collectivism of Bakunin and Kropotkin communism question the ideal of single class consciousness, the experiment of the ideal feudal society ended in 1945 with the German mater race and single class in 1990. Emma Goldman and Kropotkin saw from beginning of Lenin took over the revolution consequences of the Feudal society of one single class, the technocratic elite become the new masters in the new Feudal Society. Bakunin split with Marx over this question. The end of the Soviet experiment shows the same characteristic of Feudal society with the repression.
But orthodoxy is not just political or social or science or art or literature, in some ways is the cultural tendency, where we are program to accept the Feudal Order.
The Catholic Church and the Evangelical movements are appealing to ideal of Feudal order (i.e. Fundamentalist in Islam or Judaism are themselves appealing to same order sensibilities). Socrates saw poets is challenge to his ideal, later on the radical Aristocrat Nietzsche question Authority of the group, but he transfers the judgment to the Aristocrat.
The question to skeptic is the question of the Orthodoxy which holds the Authority, Marquis de Sade challenge to sexuality was to the Authority of the Feudal view in sexuality.
Molecular evolution have show the pedestal and long ladder we have following from the God to level we share the same with our surrounding, where we are not any more in the realms of the Gods, and the skeptic have to confront a new orthodoxy in human level. In Dispossessed by Ursula Le Guin in the Anarchist Utopia, even in the Utopia there is orthodoxy. Every generation, wherever is found will find a Feudal Lord saying how to think or behavior a church a cult a religion defining the though a God, Gods or Goddesses. But hope for all of us we will have someone