How Much Do Wild Animals Suffer? A Foundational Result on the Question is Wrong.

by zdgroff 1 min read24th Jun 201910 comments


Cross-posted at

In 1995, Yew-Kwang Ng wrote a groundbreaking paper, "Towards welfare biology: Evolutionary economics of animal consciousness and suffering" that explored the novel question of the wellbeing of wild animals as distinct from the conservation of species. As perceptive as it was innovative, the paper proposed a number of axioms about evolution and consciousness to study which animals are sentient, what their experiences are, and what might be done about it.

Among the many results in the paper was the Buddhist Premise, which stated that under reasonable conditions, suffering should exceed enjoyment for the average wild animal. The finding matches the intuitions of many people who have thought about the issue and concluded that nature is "red in tooth and claw" in Alfred, Lord Tennyson's phrase. As it turns out, though, this "evolutionary economics" argument is wrong. This week, Ng and I published a new paper showing that the original "Buddhist Premise" does not hold: under the model in the paper, the balance of suffering and enjoyment can go either way.

The mistake in the original paper may appear technical, but it is suggestive of an aspect of wild animal suffering that prevailing intuitions in the space may miss. Our paper basically points out a math mistake in the proof that total suffering exceeds total enjoyment in nature based on a set of assumptions about the evolutionary benefits of consciousness and affective states. Ng's original paper offered an intuitive argument in addition to the mathematical one, though. Most wild animals have far more offspring than can survive to maturity, so the experience of an average animal is to be born and then nearly immediately suffer a horrible death. Based on this, Ng speculated that the Buddhist Premise should hold before offering a proof of it based on the axioms.

But the intuitive argument misses a potential evolutionary pressure the math picks up. Because the costs (e.g. resource usage) of suffering depend on the probability of experiencing suffering, when the probability of suffering increases, the severity of suffering should decrease. In other words, if the probability of being born and then immediately dying is sufficiently high, then increasing the amount of suffering is less advantageous for genetic reproduction.

Note well: suffering may very well dominate enjoyment in nature. We cannot arrive at a conclusion on that. Our point is that it does not necessarily dominate.

For me, the paper leads me to suspect that the view that suffering predominates in nature may be anchored on an incorrect result. Few people explicitly give the technical argument from the 1995 paper in conversations about wild-animal wellbeing, so it might seem to not be that influential. If you look at writings on wild-animal wellbeing, though, you find that many academic and lay research cite Ng (1995) and often cite multiple sources that all cite Ng (1995) for the claim that suffering should dominate enjoyment in nature. Many more people than realize it may have been influenced by this result. Our new paper does not show that enjoyment predominates, but it does give reason to pause and reflect on work to date.