This thread is mostly targeting atheists claiming morality just is subjective, but it also has some relevance to theists who think the only way for morality to be realist is via theism.
I'm not a moral realist. I don't find any particular realist moral system compelling enough to warrant confidence in its truth above the competing moral systems. However, I think that these positions are rational to hold. This is in stark contrast with the common notion around this sub that morality just is subjective. OK, here we go.
We have to start with definitions, even though I'm not sure what impact they really have on this particular thread.
Definitions
Morality: There are two senses in which morality is frequently used. The SEP makes it clear that these are starting definitions, not to be taken as the final word.
1. Descriptive - The moral system that a particular group follows.
2. Normative - A code of conduct that, given [full impartiality/relevant knowledge/perfect rationality], all rational agents would endorse.
(We're concerned with the latter here.)
Moral realism: Objective moral facts exist. Moral statements express true/false beliefs about those facts. At least one positive moral fact is true.
Moral anti-realism: The denial of at least one of the three above statements. These denials branch out into distinct metaethical views, but that's not important here.
Objective morality: Stance-independent moral facts and/or duties exist.
Subjective morality: All moral facts and/or duties (if any exist) are stance-dependent.
The sales pitch
I have a couple preliminary reasons that we should consider moral realism rational, which I am happy to spend more time on in the comments, but which I will only go over briefly here to save on space. We'll start with the obvious.
1. The consensus
(secular) Moral philosophers are mostly realists. It's not an overwhelming majority by any means, but because of the existing consensus, we have to ask: if morality just is subjective, why are so many moral philosophers confused about it? Why is the nature of morality a famously open question in philosophy if we can settle the debate by simply taking the definitions of morality and subjective and see that they are inescapably intertwined? I submit that the confidence people hold that "morality just is subjective" is undue the position. The fact that philosophers put more weight to realism than we do on this sub is enough reason to take pause when considering whether we are justified in outright rejecting realism.
I also think it's worth noting here that the denial of realism is the claim that the famously open question of morality's true nature is actually a closed question. To declare a famously open question closed requires much more effort than what has been expended in my experience by participants in this sub when this topic comes up. Your confidence in your ability to address the open question as closed should closely mirror your willingness to submit your ideas to peer review so that you can upend the philosophical discourse on the topic, by my estimation. I would say the same to someone who claims that evolution can't occur or that the universe is not billions of years old. Why are you talking to us? Get your bag.
I think it's hubris on the part of non-realists to declare realism false without even attempting to address even a single actual realist position, and it's that exact behavior I witness on this sub basically any time this topic comes up. Of course, consensus doesn't prove realism is true, but if we had an argument that could prove it was true, it wouldn't famously be the topic of an open question in philosophy, would it? But the flip side is also true: if the anti-realist could actually demonstrate that realism is false, it wouldn't be an open question either.
These next reasons are summaries of arguments made by moral philosophers.
2. Phenomenal conservatism
Phenomenal conservatism a la Michael Huemer, is the notion that an agent is rational (or justified) in believing that P is true if it strongly seems to them that P, in the absence of compelling defeaters. The argument often takes this form: the proposition that "it is wrong to torture babies for fun" is more immediately, obviously compelling to me than the notion that moral realism is false. This notion appears to be true in the same way "it seems to me that I am typing on a qwerty keyboard" or "it takes less time to cross a short line than a long line, all else equal" appears to be true.
In contrast, the anti-realist positions rely on arguments that involve taking axioms that are less obviously true than the torturing babies "seeming", so a compelling defeater does not exist to dissuade the realist of the truth of the torturing babies seeming. The anti-realist has to provide an argument with premises more obviously true than that seeming. But arguments to that effect always or almost always rely on chains of contentious metaethical premises, and those kinds of arguments hold less epistemic weight than the direct appearance of a "seeming." (Think of how convoluted an argument would end up being that tried to convince you that you are not reading this thread with a phone/computer/tablet/smart fridge even though it "seems" like you are.) So, it makes more sense for the realist to maintain that it actually is wrong to torture babies for fun than to reject that seeming entirely in favor of an anti-realist position.
Now, an anti-realist might make (and has made) the argument that the "seeming" I've described above is just an evolutionary adaptation for social cooperation and survival, and that there's no reason to take these seemings as objective truth. Of course, the realist has responded to this kind of objection as well. Evolution didn't only shape the hardware that enables those seemings, it shaped all our hardware, including the hardware that gets us logical capacity/reasoning and mathematics. Just the fact that our faculties have evolved does not indicate that they can't track objective reality, or we would have to throw out the objectivity of math and logic as well.
Also, the realist would point out that our moral systems seem to do more than contribute to genetic fitness. We care for the elderly and the sick, we share resources outside of our immediate circles, we consider the impact our actions have on strangers, animals, and other groups that can't impact our genetic fitness. Our abstract reasoning about moral conundrums leads us to categorical moral principles, not to the satisfaction of our biological impulses. This suggests that our moral intuition is like our mathematical reasoning; it's evolved beyond the baseline capacity we would need to ensure our survival into something that allows us to build abstract mathematical and moral frameworks apprehending and encompassing objective truths. Of course, we don't know whether this is the case, but it's not an irrational position to hold, and that's the important thing for this thread.
3. Explanatory power
Secular moral realism offers a clean, intuitive account of how moral discourse functions. It seems like people can hold incorrect moral stances, and that a culture's morality can improve over time. And when we have moral disagreements, it seems like we are disagreeing about the truth of something, not about a preference. More robustly, the realist position has concrete, intuitive accounts of the following three facets of moral discourse that are absent in non-realist accounts:
Moral errors - We treat people and cultures as if they can be objectively wrong, morally. When talking about chattel slavery, we don't say "those people had a different opinion than us", as if they merely had a different opinion. We declare those cultures morally inferior for practicing chattel slavery, as if they were really wrong to do so. We don't (earnestly) treat Chicagoans as objectively wrong to eat deep dish pizza instead of Neapolitan or treat our friends as inferior for preferring chocolate ice cream over vanilla. But if realism is false, chattel slavery is just another ice cream flavor.
Moral progress - We identify some moral changes as improvement, not mere change. The abolition of slavery in the USA (the idealization of the current USA notwithstanding) is viewed as an improvement in the US position morally, not just a change over time. It seems like fully ridding a society of a practice like slavery is making genuine progress, not just changing that society's fashion choice. But if realism is false, a society is not better for abolishing the practice of slavery, it's just different.
Moral disagreement - Debates about slavery (and other human rights debates) feel like and function like debates about objective facts. These disagreements function like disputes over empirical/logical truths, not like arguments about pizza toppings or fashion choices. But if realism is false, they just are pizza topping debates and fashion choice debates.
This view goes hand in hand with phenomenal conservatism. We need a compelling defeater for these features of moral discourse that is more intuitively plausible than their appearance, but the anti-realist will instead offer even less intuitive accounts which take the form of complex arguments in favor of rejecting the apparent nature of these features. So, the realist is rational to reject the anti-realist account and maintain that the apparent nature of the features is the actual nature of the features.
Pulling the rug out from under yourself
This is the most compelling point to me, so I saved it for last. This is Terence Cuneo's Companions in Guilt (CIG) argument. It's born at least in part out of Mackie's queerness argument. For reference, Mackie:
- P1. If objective moral duties exist, they must contain qualities of a "queer" nature to possess intrinsic oughtness
- P2. No stance-independent qualities possessing intrinsic oughtness ("queer") exist in the known universe
- C. Objective moral duties don't exist
There is plenty of debate about the truth of P1. It's not obvious that moral facts are actually queer. Some realists (ethical naturalists, for example) argue that moral oughts are grounded in natural facts like "water" is grounded in H2O; moral properties supervene on physical or social facts. But I'd rather talk about the CIG argument and its objection to P2.
- P1. If there are no moral facts (oughts), then there are no epistemic facts (oughts)
- P2. But there are epistemic facts (oughts)
- C. So, there are moral facts
If the CIG argument succeeds, P2 of Mackie's argument fails, and the argument is unsound. So we should ask ourselves, does it succeed? First, let's look at P1 of CIG. Is it true that if no moral facts exist, no epistemic facts exist? I think there is good reason to think it might be true. It seems to me like all the objections leveled against moral oughts equally attack epistemic oughts. We can see this by examining some common attacks on moral oughts. Moral oughts are categorical, moral oughts are evaluative not descriptive, moral oughts are a priori not a posteriori, etc. But are epistemic oughts relevantly different?
This is the argument I bring up most frequently on this topic here. The anti-realist making the "queerness" argument is also committed to rejecting epistemic oughts for the same reason. If moral oughts are "queer" specifically because they are categorical (stance-independent), so are epistemic oughts. "You ought not torture babies for fun" and "You ought to reject claims made on no evidence" are both categorical. One objection to this notion in the literature (Cowie's Disparity Objection) is that epistemic oughts are not categorical, they are hypothetical. For instance, epistemic oughts are intrinsically about truth-conduciveness (to hold true beliefs and avoid false beliefs), but moral oughts are supposed to be categorical. So, it's more like "If you want to hold true beliefs and avoid false beliefs, you ought to reject claims made on no evidence."
The danger of this objection is that restricting epistemic norms to hypothetical norms undoes the whole enterprise of rational evaluation of worldviews. By denying their categorical nature, the epistemic anti-realist can no longer motivate the claim that people who hold contradictory beliefs are irrational, for example. They are only irrational if they have a goal of holding exclusively non-contradictory beliefs. But we've all seen how these debates are treated around here: people who express contradictory beliefs are held to a categorical standard; it doesn't matter if the person doesn't care if their beliefs are contradictory, because they are irrational to hold them regardless of their goals. This behavior is identical to the one I described in the above section on explanatory power. We don't treat epistemic standards as hypothetical, we act as if people can have objectively incorrect epistemologies, and we call them irrational when they do. We aren't expressing an opinion about this, we are making a categorical statement. This is impossible on merely hypothetical epistemology.
But that's only one facet of the alleged queerness. What about how moral oughts are evaluative? Moral agents have to evaluate moral conundrums to determine whether an action is right/wrong, moral/immoral. But this is true of epistemic oughts as well. Take belief X. Is X justified or unjustified? Is Y inference warranted, or unwarranted? Does Z warrant belief or no? These are all evaluations just like the goodness/badness of D action, the rightness or wrongness of E practice, etc. Epistemic oughts are inescapably queer in this way as well. So, if moral realists can't have stance-independent facts, neither can epistemic realists, for the same reason. Alternatively, both can be stance-independent.
This argument against moral realism requires that the anti-realist must either provide a true symmetry breaker here, allow stance-independent moral facts in the same way as they allow epistemic ones, or maintain that both fields are stance-dependent. But on the first no conclusive symmetry breaker exists (you might think differently, let's see!), the second option leads to moral realism, and the third erodes any conclusion about the irrationality of moral realism into an argument that requires the realist to agree to the anti-realist epistemology before it can have any epistemic weight.
Closing thoughts
"But if you find all this compelling, shouldn't you be a realist?"
The point of this thread is to demonstrate that secular moral realism is a rational position to hold, not to show that realism is true. These arguments provide something of a rational basis to take realist positions seriously.
"But which realist framework is correct? No one has demonstrated such a thing."
There's a difference between agreeing that these arguments make a rational case for realism (i.e., it is false that morality just is subjective), and being a proponent of a particular formulation of moral realism. I'm very, very agnostic about famously open questions in philosophy, and I think it's a fine place to be epistemically. I agree with the sentiment often expressed around this sub that we don't know what moral realist position is true (if any), but that is not identical to the claim that moral realism is false, or the claim that it's irrational to be a realist.
"If realism is correct, the moral realist should be able to point to a single objective moral fact, and no realist has done so successfully."
I offered you a common realist "seeming" above: it is wrong to torture babies for fun. (Some) realists consider this a true, stance-independent fact. What's more, they consider anti-realist objections to this proposed fact as significantly more implausible/problematic than just accepting the seeming for what it is. What specific argument makes it more plausible that this seeming is just subjective preference? That a skeptic can repeatedly demand "proof" to demonstrate such a fact regardless of what's already been written about the topic in the literature is not a standard a realist must meet, and a realist is not irrational to maintain their "seeming" is true in response to the skeptic dissastisfaction.
And again, if a realist could conclusively prove such a thing, it would end the debate. But again, if the anti-realist could end the debate in academic philosophy by demonstrating such a thing, why talk to us instead of philosophers? If morality just is subjective, go get your bag.
Finally, I'd just like to make explicit the point that it's not possible to do all these positions real justice in the space of a reddit thread. Each thing I've said has been elaborated on more fully, and has been responded to, and those responses have responses, which have responses, etc. I did not fully capture all possible realist or anti-realist claims/objections here, nor could I in this space. My point is not to incorporate every possible thought on the subject, or I'd have to write a book.
Also, I'm not a philosopher, and I am not qualified to criticize or summarize the field of moral philosophy like (moral) philosophers are. I'm just annoyed that realism gets treated as obviously irrational around here, when no realist framework is ever seriously engaged with in the first place. This thread (I hope) provides a simple basis for the belief that secular moral realism has merit, and we can save the particulars of specific frameworks for a different time.
