Within hours of the infamous event now known as the “Las Vegas Shooting,” the perpetrator’s life became an open book: his hapless girlfriend, his financial record, his criminal dad, his clueless brother, his social media activity (none), his neighbors, his hard drive. His organic hard drive—that is, his brain—was removed during the autopsy and shipped to a specialized lab to probe for defects.

Within days, frustration mounted. ISIS made frantic signals, hoping to co-opt the event (and renew relevance) for itself, but there’s no evidence that Stephen Paddock was radicalized by Islam, or had any religious leanings at all. Or political leanings. Or strong affections or hatreds. We’re mystified; all we can do is chalk it up to something called “evil.” Another archvillain lands on the dustbin of history, along with the Orlando shooter, the Charleston shooter, and a string of random assassins going back to 1966 and Charles Whitman in the University of Texas tower.

Though brain probes and hard drives may hold partial answers, “evil” remains the default explanation for the careful planning and determination required to carry out such an act. Why did Dylann Roof participate in a church Bible study for almost an hour before opening fire on people whose heads were bowed in prayer? What kept Paddock on a systematic path to mass murder for weeks, if not months? Clues strewn in the wake of a shooter’s past may indicate certain leanings toward violence, but not the rock-solid determination to do it. These were not crimes of passion—passion we understand. But that vacant space in the heart of a cold-blooded killer mystifies us.

To say it was filled with evil is to say nothing. And “nothing” may be closer to the truth than we realize, because evil, according to Augustine, is not a “thing” at all.

Rejecting God therefore creates a hole in the human soul, and whatever fills that emptiness is the residue of corrupted being.

While thinking all this through, I reviewed the Bishop of Hippo’s “privation theory” of evil. This famous theological conundrum speculates how, in a creation pronounced good by its Creator (who should know), falsehood, theft, and even murder so quickly flourished. If God created all things and evil is a thing, then it must follow that God is the creator of evil—a conclusion that devastates our faith. Augustine did not deny the problem, but believed it was misunderstood. What if evil is not actually a “thing”? What if it is instead the absence of a thing?

In The City of God, he summed it up this way: “Evil has no positive nature, but the loss of good has received the name ‘evil.’” He reasons that God is the source of all being, and being is good in itself, and no goodness exists outside of God. Rejecting God therefore creates a hole in the human soul, and whatever fills that emptiness is the residue of corrupted being.

The privation theory isn’t perfect—no intellectual heavy-lifting could encompass this great mystery—but it seems to come close. That doesn’t of course mean that unbelievers are potential mass murderers. That’s a particular sin that requires a particular skill set. But we all partake of emptiness. In The Great Divorce C.S. Lewis pictures condemned souls in hell as consumed by their vices. After witnessing a silly old woman reject potential glory in order to keep complaining, Lewis’ mentor explains that she has ceased to be a grumbler and become a grumble: “The whole difficulty of understanding Hell is that the thing to be understood is so nearly Nothing.”

The collapse of a human being can happen on this side of the divide, too: Did Hollywood mogul Harvey Weinstein (for example) cease to be a predator and become a predation? Or is there enough of a person remaining in him to repent? Only God knows.

The idols one embraces while turning away from God can’t see, hear, taste, or touch, and “those who make them become like them” (Psalm 115:8). The bad news is that we don’t recognize these empty souls among us. The good news is that good will eventually overcome by its very nature. Something always defeats nothing.