We just can't seem to get enough of zombies. They're everywhere: comics, novels, television shows, movies, scholarly conferences, college courses, and even PhD dissertations. Type "zombies" into a Google search and you'll get nearly 91 million results.

So we're clearly fascinated. But why? How is it that the "living dead," animated corpses with a savage hunger for human flesh, have so captured our imaginations?

Here's the short answer: they satisfy a powerful archetypal need that most of us aren't even consciously aware of having.

Over a century ago, sociologist Max Weber argued that as societies grow increasingly secular, their corporate understanding of reality transitions from "enchanted" to "disenchanted."

For our ancestors, says Weber, reality was "enchanted," shimmering with "mysterious incalculable forces," typically expressed in religious language, which superimposed transcendent meaning on everyday life. But for secularized moderns, all this is implausible. Reason has replaced faith, and science has demolished the religious beliefs by which our ancestors oriented themselves. We dwell in a "disenchanted" or "desacralized" world.

Well, not quite. The truth of the matter is that no society ever becomes fully secularized. The hunger for a transcendent dimension to reality--for an enchanted world--remains a basic human drive, and if it can't express itself in overtly religious imagery, it'll search out symbolic substitutes. So, for example, psychologists become modernity's priests, invested with awesome authority to hear confessions, bless, and heal. Political allegiances substitute for religious communities, and partisan feuds take on the rhetoric of cosmic struggles. Self-improvement replaces spiritual discernment. Patriotic holidays and rituals stand in for religious holy days. Our chthonic yearning for something greater than ourselves plays out again and again, even in a supposedly disenchanted world.

One important archetype that gets renamed and redistributed in modern society is metaphysical evil, or the Devil. Its psychological importance can't be underestimated; it helps us cope with those acts of wickedness--torture, genocide, child abuse--so numbingly sinister that chalking them up to mere human agency is unsatisfyingly inadequate. Our ancestors personified metaphysical evil in the form of a demonic enemy, Satan, who roams the world like a roaring lion seeking human prey. Their "enchanted" belief in the Devil's machinations provided them with an explanation for evil that protected them from the far worse alternative that wickedness is gratuitous and spontaneous. Moreover, it gave purposeful direction to their lives by offering them the opportunity to enlist in God's grim but ultimately triumphant crusade against evil.

Most people today, even religious ones, no longer believe in the reality of a metaphysical source of evil, much less its personification as Satan. Nor have they an explicit sense of soldiering in a cosmic battle between divine good and hellish evil. But both archetypes are so hardwired in our psyches that they recur again and again, finding a home in any symbol that can express them.

And here's where we cue the zombies. They're today's Devils, modernity's version of the Great Enemy. We re-enchant the world by attributing to zombies qualities that our ancestors believed belonged to Satan. Zombies allow us to scratch our itch for archetypal symbols that hold deep meaning for us while allowing us to jettison pre-modern religious language that no longer speaks to us.

So for us, Zombies become roaring satanic lions hungrily searching out prey. They're concrete personifications of our deep and ancient sense that evil is somehow mysteriously nonhuman in origin, even though it uses humans as its agents. Zombies reek of death and the grave--the underground, where Satan and the damned traditionally dwell. Their bite mutates human victims into zombies, just as Satan's embrace mutates humans into slaves. And the cosmic battle theme between good and evil is also present: in all zombie stories, a valiant band of humans, typically led by a Savior-like figure, risk their own lives to rescue humankind from damnation.

No one believes that zombies actually exist. But our fascination with them points to the latest recurrence of the very same archetype that for earlier generations was communicated in explicitly religious language. We're more deeply rooted in the enchanted world of our ancestors than we suspect.

So the next time you watch a zombie movie, be aware that your forebears are seated alongside you.