by Brian Tomasik
First written: 28 Nov. 2016; last update: 28 Nov. 2016


This piece replies to some points in Michael Plant's article "The Unproven (And Unprovable) Case For Wild Animal Suffering". I agree with some of Plant's contentions. My main disagreement is that I think our assessments depend heavily on our values, and relative to the values of a significant minority of people, the net balance of hedonic experience in nature is pretty likely to be negative, while for many more people, the matter is less clear.

My values vs. my factual beliefs

My position on the net balance of hedonic experience in nature can be confusing.

First, I'm an anti-realist both about moral value and even about consciousness itself. I don't think there's an objective fact of the matter about how intense a given experience is, or how to compare the magnitudes of pleasures vs. pains. There are many objective measures of these things relative to some precise specifications, but it's a moral question which specification(s) we want to use. For example, one could crudely measure happiness as the number of neuronal firings per second in hedonic-hotspot regions of the brain, and suffering as some comparable measure for negative experiences, but it's not clear that we should directly sum these quantities for hedonistic-utilitarian calculations. Of course, this example is a bit of a strawman, since few hedonistic utilitarians would endorse the procedure just described. But there are countless possible more complex and nuanced measures of wellbeing, and it's up to an individual hedonistic utilitarian to decide which measure(s) she wants to optimize for.

Given that happiness and suffering aren't quantities whose meanings everyone agrees upon, it becomes unclear what the difference is between negative and non-negative forms of utilitarianism. A person who is considered by others to be a negative utilitarian may just feel that he's a regular utilitarian who uses a definition of suffering according to which suffering is vastly more intense than most people assume. In light of this problem, I think the best way to define "negative utilitarian" is just "someone who gives (much) more weight to suffering than most other utilitarians do when evaluating situations". For instance, in a world where most people only gave moral weight to happiness, Jeremy Bentham would be a (weak) negative utilitarian.

In light of the above points, there's no fact of the matter about whether nature contains a net balance of happiness or suffering; that depends not just on empirical facts about animal brains and behaviors but also on value judgments. Personally, I'm close to a strong negative utilitarian, so it's very clear to me that there's net suffering in nature. Conversely, there are people in the world whose values imply that there's almost certainly net pleasure in nature.

While my own values imply a high degree of certainty on net suffering, there's a further question we can ask: What fraction of other people would decide, based on their values, that there's net suffering in nature, after more thorough study of the matter? That is, imagine that we know all there is to know about psychology, neuroscience, ethology, etc., and suppose people have a chance to experience a wide range of intense pleasures and pains during their lives. At that point, what fraction of those people would conclude that nature contained more suffering than happiness? I think it's plausible the answer here is "more than 50%", but this is pretty unclear, and it seems likely that there would remain some people on both sides of the issue. The question is confounded by the problem that most people aren't utilitarians, so their judgments would be biased by other factors. We could restrict the set of people under consideration to just hedonistic utilitarians, although this might introduce its own biases -- e.g., hedonistic utilitarians may care more about happiness than other people do, are overwhelmingly likely to be male, etc.

All told, the distribution of opinion on this topic is and will likely remain diverse even after more facts become available. In general, when I present arguments for net suffering in nature, my aim is to say something like: "Even if you consider yourself a non-negative utilitarian, here are some major sources of suffering in the wild that might still incline you toward thinking there's a net balance of disvalue." Often I put this point in a cruder form, like "There's plausibly more suffering than happiness in nature", because this statement is a relatively concise way to say roughly what I'm trying to get across using ordinary language. The full fine print on that statement is complex (having taken several paragraphs to explain just now).

Replies to specific points

Now I'll reply to some points of Plant's article with which I disagree, but there are many other statements to which I have no objection.

I quote Plant's article using green italics and then write my replies directly below in normal text.

for the zebra’s death to cause so much suffering it outweighs the pleasure in the rest of its life, that means each minute of its death would need to be at least 2,190,000 times more painful than the average minute of the zebra’s life.

People vary widely on questions like these. For myself, it's viscerally obvious that a minute of being eaten alive by lions would be more significant than millions of minutes of mild (and occasionally, intense) happiness put together. Other people would consider the tradeoff obvious in the other direction. There's no neutral standpoint from which to make these judgment calls.

Zebra diseased from Bacillus anthracisAs an empirical matter, I suspect that most people would accept this tradeoff if you presented it to them. However, a significant minority would likely refuse. This survey question ("Pain-pleasure tradeoff") is poorly worded, but insofar as we can extract information from it, it suggests that a significant minority of people would side more with my view on the predation-happiness tradeoff.

Still, I would guess that many (maybe a majority of) people would, even after learning more, decide that a typical zebra who lives a full 25 years has a net positive life.

if some aliens looked at human life and noted that we are often ill, hungry, bored, stuck in traffic and grieving for the loss of our loved ones, then concluded our lives contained more suffering than happiness we’d think that was a mistake on their part and they’d conducted too partial an analysis.

Given that some humans are being brutally tortured right now, I think it would be unconscionable to, say, be a God who created our present world (even if it weren't possible to create anything better instead). The present world, even just for humans, is far more gruesome than Omelas.

But yes, as an empirical matter, I agree that most people endorse the current aggregate experiences of humanity on balance. Many people would even endorse creating humanity if they were in God's shoes -- although I suspect the fraction of people willing to create our human world ex nihilo would be far smaller than the number willing to keep it in existence, in light of act/omission distinctions, etc.

We often don’t want to swap places with other people (or animals) even though we think they are happy

Rather than talking about swapping places, my phrasing was: "would be better not to exist than to find oneself born as an insect". This is an important distinction because almost no one would want to swap places with an insect in the sense of giving up one's present life in order to be the insect. Rather, the question is whether being an insect is better than not existing at all.

With that cavil aside, I agree that there are dangers when doing this kind of imagination, because we may smuggle our current feelings into how we conceive of the scenario. For instance, people might assume they wouldn't want to be a dung beetle because eating dung is disgusting.

In fact, "becoming another organism" is sort of incoherent, because if you're fully transformed into another organism, then there are no traces of "you" left behind, so all we have is that organism itself. Still, I think this incoherent imaginative act of "becoming" another organism is helpful at eliciting empathy. Indeed, "imagining oneself as another" is the core of empathy, even though it's technically incoherent.

we should avoid carelessly straying into anthropomorphism and judging their lives by our standards. We need to try to understand what it’s life for an insect to be an insect, rather than for us to be an insect.

I largely agree, but I would add that there's no morally objective measure of the goodness or badness of an animal's life, or even the "happiness minus suffering" of the animal's life. We ultimately make those judgment calls based on our own feelings, although an animal's self-reports and revealed preferences can certainly influence our judgments.

Moreover, we run into problems when trying to do interorganismal comparisons of utility (or even comparisons within an organism across time). Suppose one animal is unwilling to be born into a life that will end with it being eaten alive, no matter how happy its prior life would be. Meanwhile, another animal is willing to accept that tradeoff. Suppose we have to choose whether to preserve a habitat that inevitably will give rise to both types of animals. How do we reconcile these conflicting preferences in a way that judges the animals' lives by their own standards? Their standards are in conflict. There is no right answer; we just have to side with one of the animals over the other.

if that zebra was born with a comparatively low desire for food, and it gave them minimal pleasure, you would expect other zebras to out-compete her for resources, causing the low-pleasure zebra not to pass on her genes.

In general, I agree. Of course, there are many exceptions to this kind of reasoning. For example, a depressed person might not experience pleasure from eating but merely a reduction in suffering, while still having a net-negative experience. Behaviors can be motivated to reduce suffering and/or to increase happiness.

I suggest a more promising strategy is understanding pleasure and pain as reward mechanisms evolved to help animals survive and reproduce (e.g. see (Ng 1995).

I agree this is a helpful framework, and it can yield some tentative conclusions, such as that the badness of extreme injury relative to the goodness of a year of life may be less severe for shorter-lived animals. Conversely, the same kind of reasoning suggests that in long-lived animals, severe injuries (such as having one's flesh torn open) may entail suffering that outweighs many years' worth of orgasms, because a severe injury of that kind may reduce one's expected future offspring by a large percentage. From this perspective, it's possible that a zebra getting eaten alive would experience more suffering (measured relative to brain processes that evolution has designed to roughly correlate with evolutionary fitness) than the aggregate happiness of several previous months or years. That said, it's not clear that zebras do have a measure of hedonic experience that tracks evolutionary fitness this precisely. (If we were instead considering a simple artificial reinforcement-learning agent that has a scalar reward value at each time step, this kind of evolutionary reasoning would be much stronger.)

one might expect k-selectors to have much greater capacity for happiness than r-selectors.

I agree that a K-strategist animal generally has more sentience than an r-strategist animal. I often take this into account in my more recent pieces on wild-animal suffering, such as this one. But even if we do this, it still seems that r-strategists probably dominate K-strategists in moral importance, perhaps by several orders of magnitude. One quick way to see this is to note that biomass of all vertebrates is, according to one estimate, less than that of terrestrial invertebrates, and the difference in neuron counts probably favors invertebrates even more dramatically. Personally, I think sentience should be considered to scale less than linearly in neuron count, in which case invertebrates become yet more important.

If you produce fewer offspring, it’s more important that they can react to circumstances to can avoid being killed and eaten, hence reward and punishment systems are important. If you produce very many offspring, they’re much less need for cognitive complexity and hedonic capacity: operating ‘on autopilot’ is sufficient for some of them to survive and reproduce.

As a general trend, I concur. However, as I'm sure Plant would agree, it's also important to look into the details of how much this trend holds. For example: "the behavioral repertoire[s] of invertebrates such as insects sometimes surpass that of mammals such as moose and monkeys."

This book's summary blurb says: "Until recently, insects were viewed as rigidly programmed automatons; now, however, it is recognized that they can learn and that their behavior is plastic." This study found "threat-sensitive learning" in mosquito larvae and explained:

To our knowledge, only one study has demonstrated threat-sensitive learning in another aquatic prey. Ferrari et al. (2005) showed that fathead minnows learned to recognise brook trout in a threat-sensitive manner. While this level of sophistication is impressive in a fish species, it is even more impressive in an invertebrate species that may spend less than 2 weeks of its life in an aquatic environment.

In any case, even if one doubts the sentience of invertebrates, there are many other r-selected taxa that most people agree are sentient, including fish and even small birds and mammals, though some of these r-selected taxa have long enough expected lifespans from birth that some people would judge there to be more total happiness.

you have to reach a conclusion about how much happiness the happy animals have compared to the unhappy ones in order to work out if destroying a given ecosystem would increase or reduce happiness. I’m not going to say anything about this, other than that it seems quite hard to do in a principled way.

Of course, the issue applies also to those who currently favor habitat preservation. Because the issues are so difficult, sentiocentric conservationists' current stance may be quite misguided (even relative to their own idealized values). This seems to argue in favor of more research, rather than assuming we should leave nature alone. But I think Plant's main point is that there's high uncertainty, not that nature preservation is more likely better than the opposite.

farmed chickens do not live in an ecosystem with other animals (if you exclude their ‘predators’, humans), so it’s easier to conduct the counterfactual analysis of what would happen if humans ate less chickens.

A thorough analysis is quite difficult, not least because chicken farms have major impacts on wild-animal populations (such as because chicken farming increases grain cultivation).

see Ord 2013 for a discussion of negative utilitarianism

See also Simon Knutsson's reply to Ord.

Speculatively, if our concern is restricted to animal suffering, wild animal suffering looks much less cost-effective than focusing on factory farming.

I agree and disagree.

First, where I agree:

  • In terms of combating short-term suffering, if reducing wild-animal populations is ruled out, then it's plausible that welfare improvements for factory-farmed poultry and fish, as well as humane stunning of wild fish, would top the list of ways to cost-effectively reduce suffering. Welfare improvements scale up better than veg outreach and also don't require as much certainty about the net impact of veg*ism on wild-animal suffering. I'm a big fan of (most) farm-animal welfare work because it can be extremely cost-effective.
  • Meanwhile, it seems harder to come up with scalable interventions to reduce wild-animal suffering without reducing wild-animal populations. One speculative proposal is to create and deploy gene drives on a large scale, but I'm skeptical about this for a few reasons. Humane insecticides are a candidate for a high-impact intervention that needn't change animal populations much, although it's unclear how feasible this idea is.

Where I disagree: I think meta-level work around wild-animal suffering could still be fairly leveraged. For example:

  • Further research to reduce uncertainty about the net hedonic experiences of wild animals would help tip some people away from an ignorance prior about the question. Even small changes in one's probability of net suffering in nature, multiplied by large numbers of animals at stake, could lead to a situation where one can push for or against various environmental policies.
  • Promoting concern for wild animals (and similar kinds of sentient creatures) may influence the values and practices of our descendants in the far future, such as whether post-humans run ecosystem simulations. Even if you think there's net happiness in nature, you might still oppose ecosystem simulations if other computations containing more happiness and less suffering could be run instead. So, for example, reducing the intrinsic value that people place on nature, relative to the value they place on the experiences of sentient creatures, could be important.

Michael Dickens makes a similar point: "But [even] if only future generations can tackle wild animal suffering, we are still faced with two big goals to accomplish now: making sure future generations care, and doing research so that we’ll know sooner what to do to directly reduce suffering."

Plant may agree with these latter points, and his main contention was that direct measures to reduce wild-animal suffering right now look less cost-effective. He says of futuristic interventions in nature: "In the (far) future, once many other problems have been solved, this may be a cost-effective way to increase happiness compared to the alternatives."

Minor quibble

The life expectancy of a zebra in the wild is 25 years.

My top result on Google for the query {zebra lifespan} is this page, which indeed says that "Zebras live for an average of 25 years in the wild." However, I'm pretty sure this number is too high, and perhaps that source means that maximum lifespans tend to be around 25 years.

This page says, "Zebras in the wild live an average of nine years. Sadly, there is a 50 percent average mortality rate for foals [...]. In captivity, the life span for a zebra extends to 20 to 40 years."

An average life expectancy of ~9 years is confirmed by this study, which presents the following information:

In any case, this makes little difference to Plant's overall argument.