As a Thomistic Aristotelian I do believe in other weird kinds of things: essences, for example, and distinctions between substances and accidents. These are slightly more technical things than ghosts, but equally silly in the mind of the materialist and the empiricist. I happen to think that there are no non-arbitrary reasons to reject such things and plenty of non-arbitrary reasons to accept them, but these are subjects about which reasonable people can agree to disagree, at least in my opinion. But for some reason, when it comes to ghosts and the like, I have a tendency to think that there's no way a reasonable person is going to take the idea seriously even for a second.
Hence you can imagine my surprise to find that some people, including some people whom I generally admire in the intellect department, appear to be endorsing the idea that Cho Seung-Hui, the young man who murdered more than 30 people at Virginia Tech before killing himself, did what he did because he was possessed by a demon. There is an interesting blog item about it at Spirit and Life, written by a priest by the name of Thomas Euteneuer. Euteneuer accepts the very real possibility that Cho was indeed possessed when he acted as he did. In my view, this is utter nonsense. Indeed, it is not merely utter nonsense, it is literally nonsense, and it is not something that I think any intelligent person can reasonably endorse.
First, it is unscriptural. The cases of demon possession in the New Testament are exclusively cases in which a demon is tormenting a person internally, not driving a person to commit evil acts against his will.
Second, speaking of acting against one's will, the idea that demons can, by means of possession, drive people to commit evil acts, destroys the notion of free will and takes away individual autonomy and moral responsibility. On this point, Euteneuer writes:
Well, first let me say that, as a Catholic priest, I have seen and worked with my share of possessed and obsessed individuals. It’s entirely possible for someone to be at once responsible for his own acts and totally under the influence of the devil in committing them. In this case, Cho pulled the trigger, but the devil was the author of the deed. Does not Jesus call him “a murderer from the beginning”? The devil is the prime mover of all evil in the world, but human beings freely cooperate with him in their evil decisions. No one gets off the hook of responsibility by blaming the devil, but we can’t say that the devil is a detached observer to crimes like this.Virtually every sentence in this quotation begs the question, but it will suffice to point out that it is just plain silly to say that "It's entirely possible for someone to be at once responsible for his own acts and totally under the influence of the devil in committing them." This is either an outright contradiction or it is just plain bad theology. One would like to know more about how such a thing is "entirely possible", but we get no explanation, only assertion.
Third, demon possession is explanatorily otiose in cases such as this. Cho's behavior can be fully explained in terms of perfectly ordinary human motivations, mental illness, and other mundane concepts. There is literally no need to invoke some further cause, namely a "demon", to make the explanation of what he did complete. If there were such a need, then there is no reason to think that every evil act is not caused by demon possession. Sure, this act seems to us particularly egregious, but line-drawing is a notoriously arbitrary affair. If he had killed, say, five fewer people, would that mean he was not demon possessed? How about 15 fewer? What if he had only killed three people? Or just one? How does one know such things? It cannot be merely some vague and subjective sense of the enormity of it all, since that is nothing more than a personal and subjective judgment, and every such killing spree is, after all, nothing other than a concatenation of individual killings. If a killing spree is caused by demon possession, so is every individual killing. Yet that seems, well, rather difficult to believe, if for no other reason than that it leads to a slippery slope in which every evil act is reducible to a demonic possession, and demonic possession becomes nothing more than a synonym for "evil act". And yet clearly we distinguish between genuine demonic possession and mere run-of-the-mill viciousness.
Fourth, invoking demon possession does not seem to differ from the sort of magical thinking that always looks for a hidden variable to explain what appears to be otherwise inexplicable. Take, for example, this little gem from Euteneuer:
a crime of this immensity cannot be accomplished without a person’s total emotional commitment. After reprogramming a person’s thought patterns, the demon excites his passions to do what he wants. Others have very credibly explained how Cho’s pathetic video images imitating the Korean flick, Old Boy, were evidence of his heightened emotions influenced by violent images. He even ranted in imitation of the Columbine killers Harris and Klebold in solidarity for the deed he was about to commit. In other words, it’s very difficult to sustain such an emotional intensity about the evil he planned and carried out without some direct force multiplier.Euteneuer can't imagine an unaided human being being able to sustain "such an emotional intensity about the evil he planned and carried out", so he posits "some direct force multiplier" that is literally outside of the system. Talk about begging the question! And yet this is given as one of the necessary conditions for demon possession. And then there's this:
He plotted—like all demons from Satan to the perpetrators of the World Trade Center attacks. He bought guns and ammo, he planned the date and times and places of the murder, and he even went regularly at night to work out at the campus gym in order to look the part of a mass murderer. The devil must have been very happy to witness his prey blast his brains out after perpetrating the bloody murders of 32 innocents. That is the ultimate victory for the devil.Planning ahead is also a necessary condition on demon possession, it seems. Now there's underdetermination for you. This guy has been taking his Screwtape Letters way too seriously.
Fifth, it is way too provincial to think of acts such as Cho's as somehow fitting into a kind of paradigm of demon-possessed evil. History is long and full of far worse things that what Cho did, and it begins to seem rather desperate to explain all such things away as nothing more than cases of demon possession. It reduces the human person to a kind of automaton, for one thing, and a peculiarly simplistic one at that.
Now, don't get me wrong: I'm not claiming that there is not now, nor has there ever been any such thing as demon possession. But I don't see any reason to think that demon possession is what we see in the case of a person like Cho, or Stalin, or Hitler, and any such folks. The stories of demon possession that we find in the New Testament may, of course, be correctly describing the ontological status of the persons being described, but (a) they are clearly quite different than what Euteneuer is talking about and (b) I'm not so much of a fundamentalist as to think that the stories of demon possession in the New Testament are open to only one interpretation.
Clearly we want explanations for things like what Cho did; even more pressing is the need for an explanation when there is no evident will involved in suffering, as when a tsunami kills nearly half a million people. But I don't think it's a good idea to just make up explanations that appeal to whatever nostrums happen to be stowed away in our own peculiar ideational backpacks. That's not what explanation is all about. Maybe you have to have a little something extra in your intellectual equipment to take such explanations seriously, but I'm pretty sure I don't have that equipment, because I can never take such explanations seriously even for a second. They are laughable, in my view, and reveal more about the person who posits them than about the person who is allegedly "possessed".