Utilitarians are often accused of being excessively fixated on animals—their sheer numbers mean that nearly all the welfare in the world is experienced by animals. But I don’t think this is some troubling feature unique to utilitarianism. It’s follows automatically once one has even a modicum of empathy for animals. Once one does not arbitrarily discount the interests of animals entirely, the moral urgency of animal welfare becomes clear.
John Rawls famously proposed a procedure to evaluate the importance of the world’s issues impartially and without bias. The proposal: imagine making decisions behind a veil of ignorance, unsure which of the affected parties you are. For instance, suppose Jeffrey Dahmer is deciding whether he should kill and eat people. Well, if he wasn’t sure whether he was the one who would be doing the eating or the one being eaten, he obviously wouldn’t support the killing and eating. No one in their right mind would take a 1/2 chance of being killed and eaten for a 1/2 chance of deriving whatever benefit Dahmer got from cannibalism.
In short, the veil of ignorance makes sure your decisions are impartial. It’s very easy to be biased to overrate problems that affect you. By imagining you don’t know who you are, you can no longer tilt the scales in favor of problems that affect you. You must include everyone behind the veil—a white person couldn’t justify anti-black racism by arbitrarily excluding black people from the pool of possible identities. You have to count everyone’s interests.
Now, perhaps the veil of ignorance isn’t a perfect procedure. It requires you be impartial—but perhaps you get to be partial towards your loved ones. Perhaps you get to save a family member over two strangers, even if you’d save the two strangers from behind the veil of ignorance.1
But even if this is right, the veil of ignorance is a decent guide to deciding which things are important. If you’d care overwhelmingly about an issue behind the veil of ignorance, then the issue is quite important, and you should take it rather seriously. The veil of ignorance tells us which things impartially matter, and any plausible ethical view takes seriously the things that matter impartially—even if bringing about impartial value doesn’t exhaust all of ethics.
But when we apply the veil of ignorance to animals, it becomes obvious that animal welfare is by far the most important issue in the world.
A first thing one notices when they imagine they’re equally likely to be any of the conscious creatures ever born is that the odds they’ll be a human are very low. It’s about 600 times more likely that you’d be born this year as a chicken in a factory farm than a human. In fact, the odds you’d be born as a chicken in a factory farm this year are about as high as the odds you’d be born as a human ever, in all of history up until this point. Approached this way, caring about chicken farming doesn’t seem like some weird obsession of utilitarians. Behind the veil of ignorance, we’d all care about it. Our concern about chicken farming alone could very well dwarf our concern about all human problems.
Around 440 billion farmed shrimp are born, reared, and killed each year. Even if you think there’s only a 10% chance shrimp are conscious, the odds you’d be born a farmed shrimp tortured for its entire life this year alone are over 350 times the odds you’d be a human born this year. You’d be much likelier to be born a farmed insect this year than a human in all of history.
But this is all a rounding error compared to wild animals.
You’d be more than 10 times likelier to be a wild bird alive now than a human. Same roughly with wild mammals. With reptiles, the numbers are more dismal—you’d be somewhere between 10 and 10,000 times likelier to be a reptile than a human. With fish, even if there’s only a 10% chance they’re conscious—an implausibly low estimate—you’d still be about 10,000 times likelier to be a fish than a human. Amphibians are roughly on the same scale as fish.
The things you’d really start to prioritize are insects (particularly relative to current practices which neglect their interests entirely). Even if you think there’s only a 1% chance that insects are conscious, you’re still about a million times likelier to be an insect alive today than a human. And that’s not even taking into account marine arthropods like shrimp.
You should have empathy for other creatures. It would be wrong to stab me because you know that if you were me, you wouldn’t want to be stabbed. But if you have empathy for other creatures, if you evaluate harms to them impartially, then it becomes overwhelmingly clear that human problems are a rounding error compared to harms to animals. Our failure to extend empathy to animals is purely a result of selfishness; it would cease immediately if we had any chance of being them.
If making decisions behind the veil of ignorance, you wouldn’t treat humans as the only creatures that mattered. If you were just as likely to be any of 15,000 shrimp anesthetized per dollar given to the shrimp welfare project as the one human giving the dollar, then even if you suspected shrimp weren’t conscious, you’d support donations to help them. If the odds you’d be a human were a rounding error compared to the odds you’d be a wild animal, you’d immediately recognize that wild animal suffering is by far the worst problem in the world and that we should do something about it.
There are all sorts of excuses for ignoring the welfare of animals. They have limited mental capacities. They’re not human. They’re not a part of an intelligent species. But ask yourself: would you take seriously any of these excuses from behind the veil of ignorance? If you were 100,000 times likelier to be a fish than a person, would you really deny that it’s a big deal when fish suffocate to death in a barrel? If you were really impartial, vastly likelier to be born an animal than a human, would you really treat these as good reasons to count their interests for near zero? Of course not. No one would.
Now I imagine the reply will generally be that we shouldn’t actually reason as if we were behind the veil of ignorance. We’re not behind the veil of ignorance! But this is no more convincing than an anti-semite saying he can ignore the interests of Jews because he’s not Jewish. You should have empathy for others. Their interests matter! If you’d care deeply about a problem if you were impartial, then it would be an ethical mistake to completely ignore that problem.
The veil of ignorance is a nice way of cutting through the bias and unjustified lack of empathy. It tells slave owners not to own slaves, for they would not own slaves if they might end up as slaves. It tells nations not to plunder and kill enemy nations, for they would not do that if they might be the ones plundered and killed. And it tells us to care about the animals crying out in cage, barn, and field—even the small, weird ones we normally neglect.
The only question: will we listen?
The veil of ignorance also seems to imply on its face that you shouldn’t care about bringing people into existence if they have below-average happiness, but that’s easily fixed by including possible people behind the veil.
For what it's worth, I don't think you've presented the Rawlsian version of the veil of ignorance here because your argument relies on beings from behind the veil knowing, e.g., that they'd be much more likely to become a shrimp than a human.
From the authoritative Utilitarianism.net: "The “veil of ignorance” thought experiment was originally developed by Vickrey and Harsanyi, though nowadays it is more often associated with John Rawls, who coined the term and tweaked the thought experiment to arrive at different conclusions. Specifically, Rawls appealed to a version in which you are additionally ignorant of the relative probabilities of ending up in various positions, to block the utilitarian implications and argue instead for a “maximin” position that gives lexical priority to raising the well-being of the worst-off."
I think it's fair to say "well, a version of the veil of ignorance that prevents you from knowing the probabilities is arbitrarily restrictive," but I don't think it's fair to say (on the basis of what you've argued here) "Rawlsians should be on board with strongly prioritizing animals."
I wonder how you should anthropically weigh all minds when you do the veil of ignorance exercise. Definitely not by entity-counting, as there is no sharp discontinuity between conscious and non-conscious matter. Is there a "standard" answer?