2 Reasons Why Common Sense Morality Can't Be (Very) Wrong

Extremely bizarre conclusions from an ethical theory are a reductio ad absurdum against that theory

Over the past few months I’ve been debating some Utilitarian philosophers from the left-liberal/LessWrong/Effective Altruism sphere who have an extreme focus on shrimp welfare. These Utilitarian philosophers are of course very concerned with maximizing pleasure and minimizing pain so, since there are trillions of shrimp in the world, they think that shrimp welfare is the world’s most important moral issue¹ - far more important than starving children or any other form of human suffering. Furthermore, since it’s quite likely that the average shrimp lives a life with more pain than pleasure, these Utilitarian philosophers think it would probably be a good thing if all life on Earth were exterminated (Edit 5/3 They think that wildlife should be exterminated but humans should not be exterminated because humans can produce large amounts of utility in a long term transhumanist future²).

I think it would be very bad thing to exterminate all life on Earth.

1. Moral Principles Come From Judgments of Particular Cases, Not The Other Way Around

I am joined in my pro-human, anti-extermination-of-all-life position by

Lyman Stone

and

Charles Amos

. Lyman Stone argued that if shrimp welfare matters morally, then it may be the case that human progress since 1700 has been morally bad. That clearly can’t be right, so shrimp welfare must not matter morally.

Silas Abrahamsen

accused Stone of faulty reasoning. Abrahamsen claims that an act which seemed to be morally fine may turn out to be horribly morally wrong if it turns out to violate our moral principles in a way that we didn’t expect. But that’s wrong, because it confuses the epistemic order of moral principles and moral judgments of particular cases.

The way that we get our moral principles is that we consult our intuition about particular moral questions. Is it morally ok to murder Steven because he said your t-shirt was ugly? No. Is it ok to murder Sally because she didn’t like your instagram post? No. From these particular cases we derive the moral principle that it’s wrong to kill people for capricious reasons.

The shrimp-welfare-enthusiasts get ethical reasoning exactly and totally backwards. You shouldn’t start with a principle that X is bad and then find out which actions have consequences that minimize X. Rather, you should reason from clear cases. You should start by considering which actions are obviously wrong and which actions are clearly permissible, and then you should make judgements about less obvious cases based on whether or not they differ from one of the obvious cases in a morally relevant way.

Abrahamsen writes:

we shouldn’t throw out our… moral principles in order to preserve the moral judgments [about particular actions]

But this gets it backwards! We arrived at our moral principles by considering our judgments about particular cases! If you thought you had figured out a moral principle, but then you find out that it doesn’t fit with a clear moral judgment of a clear case, then you need to go back and re-examine the principle.

1A. Reductio Ad Absurdum Arguments

The shrimp-welfare-enthusiasts actually agree with me about the proper relation between moral principle and particular moral judgments when it comes to other subjects.

The shrimp-welfare-enthusiasts like to say that Catholic Natural Law theory must be wrong because it implies that it is always morally wrong to drink diet coke³ - even if drinking Diet Coke were the only way to stop the universe from being destroyed. But if they’re willing to just throw up their hands and say “the world can be weird, we should expect the morally right thing to do to be wildly different from our common sense judgements” then on what grounds can they use the diet-coke-is-always-wrong result as a reductio ad absurdum against Catholic Natural Law theory?

2. God Would Not Give Us Wildly Wrong Moral Intuitions

If shrimp pain is the most morally consequential thing on Earth, then nearly every goal that anyone has worked and sacrificed for has been a morally bad goal. Sartre talked about a person who had to choose between being with his dying mother or joining the French Resistance and Sartre claimed that there could never be an objective basis for choosing one of those two goods over the other. But according to shrimp-welfare-enthusiasts, both are bad; you ought to spend your time rescuing shrimp instead.

Nearly every goal which anyone has ever pursued, every action which anyone has ever taken, every moral emotion nearly everyone has ever felt, has been morally wrong according to shrimp-welfare-enthusiasts.

If there is a God and if God is good, then God would not give us moral intuitions so wildly out of step with what is truly good. A good God would not set us up for a life oriented around the pursuit of things which are morally unimportant. Therefore, if you believe in God you should think that our common sense moral intuitions are basically correct.

2A. Runaway Skepticism

Bentham's Bulldog

claims that we shouldn’t put much stock in common sense moral judgments because the world just “might turn out to be morally weird”

certainly almost everything else about the world has turned out strange upon thorough investigation. Quantum mechanics, the deepest layer of reality, is about as weird as anything could be.

The fact that the world has repeatedly turned out to be much stranger than we thought should lead us to abandon the widespread a priori refusal to recognize that the world is very different from how we thought.

But the world hasn’t turned out to be much stranger than we thought - not to the degree that it would be strange if the most morally important thing were shrimp welfare rather than human civilization. The vast majority of common sense beliefs have turned out to be correct. Many people might incorrectly believe that Napoleon was short for his time period, but everyone correctly believes that he was taller than one inch and shorter than 100 feet. Most people always believed that wood burning fires are hotter than water ice, and modern science has proven that common sense belief to be correct. The masses correctly believe that dogs are animals rather than robots and Napoleon was a human rather than a piece of Parmesan cheese.

Furthermore, if it really were the case that common sense had been completely wrong throughout most of human history, that would be an argument for moral nihilism, not an argument for shrimp welfare. If you reject the moral intuition that human civilization is more important than shrimp because “maybe the world is morally weird” then on what basis can you accept the moral intuition that pain is bad?

Key Takeaway #1: Starting from moral axioms is the wrong way to do moral reasoning. Instead, you should start from clear moral cases, and then make judgments on other cases based on how similar they are to the clear cases.

Key Takeaway #2: Shrimp-welfarist Utilitarians stick to their guns and say that human civilization might need to be destroyed in order to reduce harm to shrimp. Catholic Natural Law theorists stick to their guns and say that sodomy (and maybe drinking Diet Coke) are morally wrong activities which can never be done, even to save the Earth.

Key Takeaway #3: Common Sense moral judgments must broadly be right because God would not equip us with wildly mistaken moral intuitions.

Key Takeaway #4: Runaway skepticism is ill-founded. Most common sense opinions have turned out to be true. The few that turn out to be false just get more press coverage.

1. Or maybe the most important issue is insect suffering. There are even more insects than shrimp.

2. Bentham’s Bulldog: “Imagine that humans had all left earth and we could destroy the world, killing every living thing painlessly. I would, in an instant, support doing so.”

Ari Shtein

: “In all likelihood, we’re moral monsters and humanity is a scourge, with only some upside hidden way out in the lightcone. Unfortunately, much of that upside probably lies in the creation of morally-aligned AGI. And if we create that aligned AGI before we’ve aligned ourselves—i.e., anytime soon—it won’t hesitate to cut us out of the glorious maximally-moral future.”

Silas Abrahamsen: “Even if you think that some small amount of human meaning or whatever could in principle be outweighed, then I think it’s hard to avoid that maybe it would be an incredibly large number, but some extreme number of shrimp could outweigh human civilization.”

3. On a technicality, they may be wrong here because contrary to popular belief, Diet Coke does not actually dehydrate you. The caffeine it contains is not enough to dehydrate you by more than the amount of water in the Diet Coke. However, it’s possible in principle that there could be a beverage which dehydrates you, and it’s a devastating objection to the Catholic Natural Law theory that that theory says that it would be morally impermissible to drink that beverage, even if doing so would avert the destruction of the Earth.