William Lane Craig on Animal Suffering

For those who aren't aware of William Lane Craig, he is technically a philosopher of religion but it is probably more accurate to refer to him as a Christian apologist. He has made a number of ethically dubious claims over the years, like suggesting that the genocide of a people is morally right if God commands it, but recently he has been pulled back into the spotlight for arguing that animals lack the capacity to suffer.

In his article "Animal Suffering" and in multiple debates on related topics, WLC has made the following argument:

In his book Nature Red in Tooth and Claw, Michael Murray explains on the basis of neurological studies that there is an ascending three-fold hierarchy of pain awareness in nature¹:

• Level 3: Awareness that one is oneself in pain

• Level 2: Mental states of pain

•           Level 1: Aversive reaction to noxious stimuli

...

Level 3 is a higher-order awareness that one is oneself experiencing a Level 2 state. Your friend asks, “How could an animal not be aware of their suffering if they're yelping/screaming out of pain?" Brain studies supply the remarkable answer. Neurological research indicates that there are two independent neural pathways associated with the experience of pain. The one pathway is involved in producing Level 2 mental states of being in pain. But there is an independent neural pathway that is associated with being aware that one is oneself in a Level 2 state. And this second neural pathway is apparently a very late evolutionary development which only emerges in the higher primates, including man. Other animals lack the neural pathways for having the experience of Level 3 pain awareness. So even though animals like zebras and giraffes, for example, experience pain when attacked by a lion, they really aren’t aware of it.

The argument essentially accepts that animals feel pain but it goes on to make the more problematic assertions that: a) animals lack a meta-awareness of pain (which WLC seems to define as "suffering"), and b) that this meta-awareness necessitates a pre-frontal cortex. What this boils down to is the suggestion that animals cannot reflect on, or understand, the sensations of pain that they have and this is a condition required for "suffering".

Do Insects Feel Pain?

As you get older, do you sometimes find yourself standing in the kitchen wondering what it was that you were looking for? Do you find yourself struggling to remember the name of that movie, the one with that guy in it, where something happened at the end? When constructing your web to catch your food, do you find you are making more errors in terms of the length of the capture spiral, the number of anomalies per cm, and in four parameters of web regularity?

Okay, maybe the last example applies more to spiders than humans but researchers have recently looked at the behavioral effects of ageing on spiders and found similar patterns of cognitive decline that are often observed in humans and other "higher" animals.

Ageing alters spider orb-web construction (M. Anotaux, J. Marchal, N. Châline, L. Desquilbet, R. Leborgne, C. Gilbertb, A. Pasquet):

ABSTRACT: Ageing is known to induce profound effects on physiological functions but only a few studies have focused on its behavioural alterations. Orb-webs of spiders, however, provide an easily analysable structure, the result of complex sequences of stereotypical behaviours that are particularly relevant to the study of ageing processes. We chose the orb spider Zygiella x-notata as an invertebrate organism to investigate alterations in web geometry caused by ageing. Parameters taken into account to compare webs built by spiders at different ages were: the length of the capture spiral (CTL), the number of anomalies per cm, and four parameters of web regularity (the angle between radii, the number of spiral thread units connecting two successive radii, the parallelism and the coefficient of variation of the distances between silk threads of two adjacent spiral turns). All web parameters were related to ageing. Two groups of spiders emerged: short- and long-lived spiders (with a higher body mass), with an average life span of 150 and 236 days, respectively. In both short- and long-lived spiders' webs, the CTL and the silk thread parallelism decreased, while the variation of the distances between silk threads increased. However, the number of anomalies per cm and the angle between radii increased in short-lived spiders only. These modifications can be explained by ageing alterations in silk investment and cognitive and/or locomotor functions. Orb-web spiders would therefore provide a unique invertebrate model to study ageing and its processes in the alterations of behavioural and cognitive functions.

The details of the study can be found in the link above but one of the more interesting aspects of the article to me was the discussion on the current scarcity of animal models of ageing using invertebrates. I think this is (at least partially) a result of a pervasive belief that humans are distinct from animals, and even though over the last century we have chipped away at the dividing line between man and brute with a greater understanding of how humans and related species share commonalities, there seems to still be some resistance to extending this understanding to insects. To suggest that insects are not just automata that respond to their world based entirely on instinct can elicit surprise and incredulity despite the fact that much of our knowledge of how learning works in the brain comes directly from insects¹. Once we begin to investigate this topic, finding the similarities of cognitive functions between insect and man, finding the similarities of learning processes between insect and man, we inevitably find ourselves posing a scientifically and ethically difficult question: do insects feel pain?