Remember the movie Roadhouse? Patrick Swayze’s character (who identifies as a philosophy major no less!) utters the laughable line ‘Pain don’t hurt’ while being stitched up after a bar room brawl. Well, it turns out there is some justification for the distinction between pain that ‘hurts’ and pain that warns of danger. I came across this article by Adam Shriver who has done some work on the neurology of pain in animals. Basically, there’s neurological evidence that there is a distinction between sensory pain (which tends to discourage certain behavior injurious to the animal) and affective pain (pain that ‘hurts’). Shriver also argues that we’re very close to genetically engineering affective pain out of livestock thereby greatly reducing the amount of suffering they experience.
This is relevant to the problem of pain and various theodicies. The problem of animal pain has become a major element of the evidential argument from evil since Rowe’s famous fawn thought experiment. Animal suffering also features prominently in Paul Draper’s formulation of the evidential argument from harm. He argues that the fact that pain and pleasure are tied to reproductive success rather than serving any higher moral purpose (at least in the case of non-human animals) is more explicable on atheism than on theism. Indeed, animal suffering is difficult to account for by making the standard theodical moves (free will, soul-making, etc.). The problem could be put this way: If God could have avoided non-moral suffering in his creation, he should have surely done so. Why then do we find such suffering in the animal world?
Theists have traditionally made one of two moves here: 1) How do we know that God doesn’t shield animals from pain by some miraculous means? 2) How do we know that such pain is unnecessary for the self-preservation of the organism in question? The first move belongs, I think, to skeptical theism. It lacks prima facie plausibility, although of course it is logically possible. It may have worrisome practical implications for the treatment of animals. If we think that there’s some warrant for thinking that they don’t experience pain — or at least don’t experience it in the way that we humans do — we might be less inclined to extend moral consideration to them. But leaving that issue aside, the neurological evidence that Shriver provides seems to indicate that at least some animals experience pain that ‘hurts’ in much the same way that we do. Moreover, the research seems to indicate that God had the option to create these animals without affective pain, but chose not to do so. If genetic engineering is close to removing affective pain, it would be trivial for an omnipotent God to do so, and without the need for miraculous intervention every time an animal might suffer.
The second move is perhaps more plausible, but is still problematic. The suggestion is that perhaps pain is necessary. In other words, given the kind of world God chose to create, creatures need pain in order to avoid injurious behavior. A non-theist might suggest that something other than pain might serve this function. Perhaps, when an organism is about to engage in risky behavior, it experiences the equivalent of a warning light or noise. This kind of qualia would be preferable to pain. However, such an experience might not do the job that pain does. Dr. Paul Brand, a Christian missionary doctor and author of The Gift of Pain, has some experience with leprosy sufferers. Leprosy causes its victims to lose the ability to perceive pain, and thus renders them incapable of avoiding self-injurious behavior. Moreover, equipping leprosy sufferers with a device that makes noise when, say, a person draws too near a hot stove, did not have a significant deterrent effect. So pain serves a biologically useful purpose.
However, Shriver’s research suggest a way around this response. Of course, pain is useful as a barrier to further injury, but neurological research has shown that sensory pain is adequate for this task. Sensory pain, or the awareness of pain, is sufficient to motivate action, but differs from affective pain insofar as the subject does not experience the pain as acutely. To quote Shriver:
“Several authors have argued that the affective dimension of pain is the relevant dimension for what we would call suffering. To see why one might think so, consider that patients given morphine experience similar effects as those with anterior cingulate lesions, reporting that they still feel pain but no longer mind it as much. This is consistent with the fact that the affective pain pathway contains more opiate receptors than the sensory pathway. We give patients morphine in order to prevent suffering, even though they still experience the sensory dimensions of pain.”
So the unpleasantness, or suffering, associated with pain can be reduced by blocking the affective pain pathways in the brain. Moreover, as Shriver notes, experiments with rats indicate that the same is true of animals. And while there was some modification of their behavior when they experienced only sensory pain as opposed to both sensory and effective pain, the experiment indicated that sensory pain alone was sufficient to enable them to withdraw their paws from noxious stimuli. In other words, the reflex action that prevents injury remains intact even if the affective dimensions of pain, i.e. the hurtfulness, is blocked. I think the implications for the problem of pain and theodicy are clear. The two theistic moves I canvassed above no longer seem plausible as answers to the problem of animal pain. Rather, it seems as though God could have accomplished his goals by sparing animals affective pain. The fact that animals do experience affective pain is further evidence for premises in the evidential argument from evil.