Of all the periods in Western history, no era gets a worse rap than the Middle Ages, which lasted roughly from 500 CE to 1500 CE. For atheists, humanists, and freethinkers, the Middle Ages are often characterized as “one thousand years without a bath,” to quote a history professor I once had, a “dark age” when the Catholic church clouded the collective mind of Europe with irrational faith and superstition. The view of many Protestants tends to be equally dim, regarding the medieval church as a degenerate institution that had fallen away from the original message of Jesus Christ (whatever that was). Realizing that anti-medieval sentiment is usually bound up with antipathy towards the Catholic church, conservotrad Catholics take a revisionist tack towards the Middle Ages and insist that it was during the medieval period that European civilization reached its pinnacle, only to be felled by the Reformation and the Enlightenment (whether the Renaissance was a good or bad thing depends on who you ask). I will deal with each of these perspectives separately.
While I would agree with many atheists and humanists that the Middle Ages were a period full of superstition and ignorance, I’m not entirely sure that medieval people were any more superstitious and ignorant than their counterparts in classical antiquity; they were simply superstitious about different things. Many people fail to understand that the Roman Empire was a very religious society with no separation between temple and state, so to speak. The most obvious example of this was the fact that the Roman Emperor was the high priest of the imperial cult and all people, regardless of their personal religious allegiances, had to pay respect to his genii (see here http://en.wikipedia.org/wiki/Genius_%28mythology%29).
The Greco-Roman world was full of religions, cults, and sects of all sorts, something that isn’t obvious if you only read works by elite philosophers like Plato, Aristotle, Cicero, Seneca, and the like. Much like how Thomas Aquinas was not characteristic of the average medieval religionist, neither was Plato characteristic of the religionists of classical antiquity. As with all pre-modern societies, magic, superstition, and ritual played an important role in classical Athens. Perhaps the most famous illustration of this can be seen in the infamous “desecration of the Herms” that occurred before the Athenian navy was to sail for Syracuse during the Peloponnesian War:
Similarly, the reason why Augustine of Hippo wrote The City of God was to defend Christianity from the attacks of angry pagans who claimed that Rome was sacked by the barbarians because the emperor Theodosius I had disbanded the College of the Vestal Virgins, thus incurring the wrath of the gods.
What is different about ancient pre-Christian notions of religion spirituality was that there wasn’t the obsession with orthodoxy and heresy-hunting that came about with the rise of Christianity; as long as you did the right rituals, the gods were satisfied, unlike the Judeo-Christian god who is concerned with the intentions behind prayers and rituals. This is also why a deity, like Isis, could be portrayed as both the goddess of love and the guardian of chaste motherhood without causing too much cognitive dissonance among her believers, whereas the church fathers spent over five hundred years trying to hammer out exactly who Jesus was supposed to be and then went about punishing their fellow believers who held dissenting views. When compared to the generous polytheism of the pre-Christian Roman Empire, I think the “persecuting society” set up in the Middle Ages (and later adopted by Islam) was definitely a step backwards.
What is true is that the advent of Christianity extinguished the classical intellectual tradition that had existed for thousands of years. Like many revolutions, it was imposed from above by emperors eager to create a Christian empire. The afore mentioned Theodosius I not only extinguished the fire of the Vestal Virgins, he also shut down the famous Academy in Athens, ended the Olympic Games, and suppressed the ancient polytheistic cults. At about the same time, the Serapeum, a branch of the Library at Alexandria, was destroyed by the Patriarch of Alexandria, Theophilus and Hypatia of Alexandria would be lynched by a Christian mob roughly fifteen years later. You can try to hem and haw and argue that Christianity saved the best of pagan culture from the barbarians as many conservotrads do (see here: http://www.firstthings.com/web-exclusives/2010/06/the-perniciously-persistent-myths-of-hypatia-and-the-great-library), but the fact is that in many cases the real barbarians were the Christians. Actually many of the “barbarian barbarians” were Christians too, albeit the wrong kind of Christians, but that’s another story.
However, I do think that the increased popularity of mystical belief systems during the later Roman Empire, from “orthodox Christianity” to the various flavors of gnosticism to neo-Platonism can be traced to the fact that the classical tradition of pure reason had run its course. Without the scientific method, higher mathematics, and the use of more sophisticated tool to examine the world (e.g., microscope, telescope, magnifying glass), ancient philosophers hit a wall. Although Aristotle performed experiments, it does not appear that any of his later disciples followed his example of seeking knowledge through empirical research. Consequently, the people of late antiquity sought to discover the truth about the universe through religious revelation, a track which that would last until Galileo looked at Jupiter with his crude telescope.
Also contrary to what many atheists and humanists believe, I don’t think that the medieval church was deliberately trying to keep the populace ignorant or trying to prevent people from reading the Bible on their own. The idea that every person above age eight of so should be functionally literate is a very modern idea, and assumes the ubiquity of a textually based culture. Most people through history, regardless of their culture, never learned how to read because it simply wasn’t necessary. Even medieval kings and nobles tended to not know how to read but not write, because writing was work and that’s what scribes were for (and let’s get real, even today many self-proclaimed Christians never read the Bible and don’t know what’s in it). Plus, without a printing press, it’s very difficult to mass produce documents of any sort, much less a Bible with thousands of pages. While the Catholic church wasn’t trying to deliberately keep people in the dark during the Middle Ages, what we do see later on in the nineteenth and twentieth centuries is the church trying to keep traditionally Catholic countries under-developed, politically, culturally, and economically, so they wouldn’t challenge religious authority.
As I have shown, when non-theistic types talk about the Middle Ages, they’re usually reacting against the idea of an “age of faith.” While the period of classical antiquity that preceded the Middle Ages was also a period of great religiosity, that kind of polytheistic culture is foreign to Westerners who are used to a Judeo-Christian model of religion. To the average non-theistic person, the intellectual output of the medieval period, particularly the work of the scholastics, appears to be ruminations on nonsense. The schoolmen may not have really debated about how many angels could dance on the head of a pin, but they came very close to it. While the Middle Ages may not have been “1000 years without a bath,” I certainly don’t think that it was the zenith of civilization either, as many conservotrads would have us believe. If humanity can’t aspire to be in a better place than it was in the tenth, eleventh, or twelfth century, then we don’t have much of a future.