High rates of infant mortality. The plague. Crops and livestock wiped out overnight. Life in 15th-century Europe was no picnic. Somebody must be to blame, but the possibility that God was behind such pain was unfathomable. So who besides God would have the power to wreak havoc on the world?

The answer, according to 15th-century Christian theologians, was witches. Their belief in witches--and their ability to persuade society in general that witches existed--took God off the hook for all the bad things that happened to good people. Stories of alleged witches' gruesome acts comforted people whose faith in God was challenged by the evil in the world, according to Walter Stephens, the Charles S. Singleton Professor of Italian Studies at Johns Hopkins.

"The cauldron and the flying broomstick are paranoid fantasies of Christian theologians living in the first half of the 15th century," says Walter Stephens, professor of Italian studies.

Stephens has devoted the past decade to the study of witchcraft theory and how it was used both to explain evil and to prove the existence of God. On the eve of Halloween, Stephens, author of Witchcraft: Sex, Demons and the Crisis of Belief, shares his expertise and debunks some popular myths about witches.

So you'll know a witch when you see one because she will be dressed in black from her pointy hat to her lace-up boots, right?

"Actually, in the period we are talking about, there was no 'uniform.' Anyone could be accused of witchcraft. Notice I say 'accused.' There's no proof that anyone in their right mind ever admitted to being a witch without being tortured or threatened with torture."

Is there any truth to the folklore that tells of witches casting spells over bubbling cauldrons and flying through the night on broomsticks?

"No, the cauldron and the flying broomstick--or chair, or stool or sawhorse, etc.--are paranoid fantasies of Christian theologians living in the first half of the 15th century. There is no reliable evidence that either of these stereotypes has anything to do with folklore or ancient traditions of pre-Christian societies. Everything we hear of these things, in a European context, comes from the pens of Christian theologians. But, of course, the theologians attribute these activities to 'the folk.'"

Were all accused witches female? And were these so-called witches the old cackling crones we see depicted in Halloween decorations?

"About 80 percent of those prosecuted, and a comparable proportion of those executed, were female. It appears that some of the people executed--male and female--were as young as 8. We don't know a lot for certain because scholars who specialize in trials--and I don't--have several decades, if not centuries, before they will have surveyed all the surviving archives of the trials. And there are many archives that did not survive. Some of the most spectacular accusations against alleged witches came not in trials but in anecdotes told or repeated elsewhere, in panicky letters, for instance. So they may often represent rumor, not fact. 'Witchcraft' was mostly rumor, when you get down to it."

Why were theologians intent on proving the existence of witches?

"Why was Joseph McCarthy intent on proving that communists infiltrated the U.S. government? One senses that something is not right with the system. It's vulnerable. It doesn't work perfectly. So it must be being undermined by extremely powerful and crafty enemies. The difference is that the United States in the 1950s had just won the greatest military victory ever, while Europe in the 1450s was recovering, just gradually, from one of the worst centuries of all time.

"It's true that the Russian and Chinese threat looked pretty credible in the 1950s despite the successes of World War II. But the 14th century had had the Black Plague, which killed about one-third of the European population. It had the Hundred Years' War, which, though intermittent, was even longer than its name suggests. It had at times as many as three men claiming to be the true pope. And on and on and on, for every kind of social and natural evil you can imagine, including spectacular infant mortality, which is why the cauldron was invented by these 15th-century McCarthys: Infants died because witches killed them, craftily and secretly, then boiled them up in cauldrons to make ointments and powders that attracted demons like Chanel No. 5, showing them whom to kill or maim among adults and cattle."

If witches and demons are evil, then why would these holy men be so interested in writing about such a taboo subject?

"Very late witchcraft theologists proclaimed that there can be no proof that God exists without proof that the devil exists: Nullus deus sine diablo. Why? Because if God is all good and powerful, then there is no excuse for evil in the world. Christians in other times have come up with sophisticated answers to this puzzle so that they don't need the devil and his accomplices to let God off the hook. But the world of the 15th century was an absolute nightmare in many respects, and the 14th century was, in general, even worse, particularly after the outbreak of the plague in 1347."

Witchcraft treatises include vivid details of women having sexual intercourse with demons. Were the authors misogynists who were out to make women look bad?

"Yes, and no. The theologians needed to explain that devils were the origin of all society's evils, so they needed authoritative witnesses that devils were real. The best witnesses are always accomplices. So far, so good. But how do you know that someone who says demons are real is telling the truth? You get them to confess to having had orgiastic sex with their demonic accomplices. Sex with demons was 'carnal knowledge' of the reality of the spirit world.

"As the Hammer of Witches proclaimed, 'The expert testimony of the witches themselves has made all these things credible.'

"An even earlier treatise claimed, in essence, that you can't have sex with something imaginary. Another went into great detail to claim that you can't have sex while asleep and dreaming. Women were the ideal lovers of demons in these theologians' view because women were thought of as sexually passive, the objects of actions performed by men. But there were theologians who even imagined sex between men and succubi, or 'female' devils--and then, often, put those men to death for confessing it. The crime was presented as something abominable to be wiped out, but it was also the best possible proof that demons were real, and thus that God was not responsible for the shambles of this world."

How many people were tried and killed as witches?

"Somewhere between 30,000 and 60,000. Historians are currently tending toward the figure 50,000 in 300 years. We'll never know for sure. The figure of 9 million that one often hears was made up in the 1970s."

Do modern-day Wiccans have anything in common with the witches of old?

"No. Modern Wiccans are aware of being dissatisfied with Christianity. Most of the people killed [in witch trials] thought of themselves as good Christians. Few of them had done anything resembling modern Wiccan and neo-Pagan ceremonies."

To learn more about Stephens' research, visit Virtually Live @ Hopkins at www.jhu.edu/news_info/news/audio-video to watch a seven-minute video interview.