Is skepticism a progressive or conservative force? It depends on what your are skeptical about.
Skepticism about the virtue of inherited social and economic arrangements has been very much part of the modern revolution. I'm thinking of someone like Tom Paine asking what weird power made people born kings so much better than people born peasants. Hostility to established churches and their influence was another major part of the radical worldview in the 18th and 19th centuries.
That is one level of skepticism; if you doubt the wisdom of the world you see around you, you may end up as a radical or even a revolutionary. But the most skeptical people, the ones who are skeptical of everything, often end up as conservatives. To people of this mindset, the current system may be bad, but at least it functions in a minimal way, which is more than can be said for whatever you dream up out of your weak human head. This is the conservatism associated with people like Edmund Burke, Disraeli, or Warren Harding.
To believe that revolution, or even reform, is going to make things better requires a sort of faith. Many people who lack that faith end up as a conservatives.
I was moved to write about this by reading a weird article titled "The Hume Paradox," written by a philosophy professor named Julian Baggini. Baggini asks, in a dozen different ways, how David Hume (1711-1776) could have been so smart in philosophy but so stupid about politics. What he means is, how could Hume have been so skeptical about received philosophical views, but so accepting of traditional social and political arrangements?
Honestly it is a bit embarrassing to have to point this out to a professor, but there is no mystery here: Hume is just a great example of the skeptical conservative type. Hume got famous for his high-level philosophical attacks on Christianity, and his attempt to reconstruct ethics on a non-religious basis. He could be completely and witheringly skeptical about some matters. Most works of philosophy, he wrote, consist of
Principles taken upon trust, consequences lamely deduced from them, want of coherence in the parts, and of evidence in the whole.
Hume's relationship to progressive political and social ideas was complex. He was hostile to slavery, and refused to worship the ancient Romans (as many of his contemporaries did) partly because their economy was based on slavery. On the other hand he was, tentatively, a racist. Looking around the world he saw that the civilizations of Europe, Africa, and East Asia were very different, and he was "inclined to the view" that this was rooted in inherent differences between the races. (Notice the lack of commitment.) In both cases he was looking at such evidence as he could find. What he knew about European colonies in the Caribbean, and ancient Rome, was to his mind sufficient evidence that slavery was awful; but the only evidence he had about the capabilities of the races (not knowing any actual Africans) was the level of their civilizations, which seemed to him to show that Europeans were somehow superior.
In Hume's time there was a great deal of agitation in Britain for radical political reform, and (except on the issue of slavery) Hume was mostly opposed. He was perfectly aware that Britain's system was unjust, but the prospect of revolution did not enthuse him. Baggini:
Another striking example comes when he astutely articulates the harms caused by inequality: “Nature is so liberal to mankind, that, were all her presents equally divided among the species, and improved by art and industry, every individual would enjoy all the necessaries, and even most of the comforts of life… It must also be confessed, that, wherever we depart from this equality, we rob the poor of more satisfaction than we add to the rich, and that the slight gratification of a frivolous vanity, in one individual, frequently costs more than bread to many families, and even provinces.”
Yet, once again, conservative doubts prevented him from advocating anything to set this straight. Creating such equality would require too much force and violence, giving the authority behind it so much power that it “must soon degenerate into tyranny.” “Perfect equality of possessions” would destroy “all subordination, weakens extremely the authority of magistracy, and must reduce all power nearly to a level.” He didn’t seem to consider that this might be a good thing, nor notice the mismatch between his alarmism about the postulated might of an egalitarian order and his indulgence of the established inegalitarian magistracy.
Baggini thinks that Hume was obviously wrong about politics, but I am not sure. If you compare the experience of Britain and the US over the time from Hume's death in 1776 to 1900, do you see much practical difference? The revolutionary US was ahead in abolishing the established church and electing a head of state, but Britain, despite its monarchy and powerful House of Lords, was much faster to abolish slavery. The two nations got to votes for all adult men and votes for women at around the same time. That's before we even get to the results of the Latin American revolutions, or the ones in Russia and China.
There is nothing absurd about Hume's politics. He was not some kind of obscure reactionary; he supported numerous minor reforms and improvements, and at least one major one, the abolition of slavery. But his age had no example of a successful egalitarian democracy that anyone could point to and say "Look, it works." So it made perfect sense that a man who was intensely skeptical of all the philosophical systems he had ever encountered would be dubious of a supposedly better system he had never seen, and that nobody knew how to make work.
In our age we like to accuse our political opponents of being insufficiently skeptical. They, we say, believe obvious nonsense, whereas we are skeptical enough to recognize nonsense when we see it. But all the major political systems depend on belief in things that are hard to prove. Skepticism can, depending on how you wield it, drive you toward revolution, reform, or the status quo, and there is nothing strange about a skeptical conservative.