I was tempted to write off this episode of Torchwood as simply a serving of horror for its own sake. Even for someone who has followed the X-Files and Fringe, and watched The Road, this episode still seemed graphically gory.

But a little thought made me realize that there is poignant depth to this particular episode. The question Gwen poses to a member of the cannibalistic village that every ten years “harvests” human beings to use for meat gets at the heart of much horror and Sci-Fi, our biggest and deepest question of all.

When we imagine aliens, we have little choice but to make them intelligible, comprehensible, no matter how much we try to give them a sense of difference. It is hard to imagine entities that are completely different than us, and the more different they are from the familiar, the more they terrify us. But even then, we can usually grasp some motive that allows us to make sense of their actions. We are needed for food. They are so much more advanced than us, that we are but pests to be eliminated from their new home. They may seem like animals to us, or we may seem like animals to them, but either way we draw on the familiar.

And so aliens and monsters do not terrify us as much as other human beings who act in ways that baffle and horrifying us. Acts of cannibalism. Abducting someone and keeping them as a slave. Murdering one’s own children. The serial killer. The very things that allow the heroes of Sci-Fi films win the day – reasoning themselves into the mindset of their adversary – seems unable to help in these real life horror stories.

It may be that in at least some instances, behind pathological behaviors is a real difference of brain wiring and chemistry, and perhaps above all else an inability to empathize with their victims.

And so these human “aliens” terrify us more than fictional one’s from outer space. And yet for all their humanness, they are in fact at least as alien from us as any entities we are likely to encounter on other worlds, if we think about it. A completely separate evolutionary history could well produce minds far more different from our own than the most gifted, the most puzzling, and the most disturbing human minds there have ever been.

And so they frighten us. And through science fiction, we have one avenue of exploring the nature of morality when dealing with situations in which common biological and mental instincts and heritage cannot be relied upon as a basis for interaction.

It is often argued that any civilization that we encounter in space must have evolved empathy to have become a civilization. Do you find that argument plausible – not to mention reassuring? If so, there is hope that in the reaches of space, as on our own world, certain horrors are likely to be the exception rather than the rule.