Myths and misunderstandings about metaethical relativism
Note: This list will be updated and modified based on user suggestions, feedback, and criticisms. The goal is to gather a comprehensive archive of bad objections to metaethical relativism as well as common misunderstandings and provide a (relatively) short response to them.
If you have suggestions on how to organize these into broader categories I will also reorder them to better fit those categories. If there’s something I don’t cover here, please leave a comment explaining what it is.
If you would like to submit your own response or commentary and I think it’s good I’d be happy to include it as a separate addendum or to incorporate it into the response here (with your permission, and with whatever form of credit you’d like to receive).
1. Relativists cannot condemn other people or cultures
This is at best only true for some forms of relativism. If you’re an appraiser relativist, you judge other people and cultures by your own standards, and nothing about your standards prohibits you from potentially considering their actions right or wrong. Things get more complicated for agent relativism. If other people or cultures have standards that differ from your own, then they are not doing anything wrong when they engage in actions that you yourself wouldn’t engage in. Things can get complicated if the agent relativist’s moral values directly conflict with another person’s moral values. If you believe you have a moral right to defend yourself from an attack, and someone else thinks it’s morally acceptable to attack you, what, as an agent relativist, do you do? Perhaps an agent relativist could tell us how to address such conflicts, but the point is that appraiser relativists can condemn other people and cultures without issue.
In addition, both appraiser and agent relativists can criticize people who act in a way inconsistent with their own standards or the standards of their culture. If a society’s moral standards hold that all citizens are equal, but members of that society nevertheless discriminate against some citizens, relativists can condemn them for failing to comply with their own moral standards.
Critics who present this objection should be more specific about which types of relativism the objection applies to (if any) and why it is that they can or cannot condemn other people and cultures.
2. Relativism leads to contradictions
Some critics insist that moral relativism contradicts itself because it allows for the same statement to be both true and false. This is not true. Relativism does not allow for the “same statement” to be both true and false. Technically, relativism holds that a statement like:
Stealing is morally wrong.
Could be true and false, but this is because relativism treats such claims as having an implicit indexical component. Consider words like “I,” “you,” or “me”. Consider the statement:
I am Lance.
Is this statement true or false? It depends who says it. If I say it, it is true. If someone who is not Lance says it, it is false. So the exact same statement, “I am Lance” can be both true and false at the same time. You can stand myself and someone who is not named Lance side by side. Every time I say “I am Lance” it is true, and every time they say “I am Lance” it is false. Why? Because the word “I” is an indexical. In this case, it refers to the person making the claim. So when I say “I am Lance” I am referring to myself, and when anyone else says “I am Lance” they are referring to themselves. The relativist takes statements like “Stealing is morally wrong” to mean something like:
Stealing is morally wrong according to my standards.
or
I consider stealing to be morally wrong.
This implicit indexing allows the truth status of the “same” moral claim to be true when one person says it but false when another says it because the truth of the claim can only be judged relative to the respective moral standards of those people.
Indexicals are a familiar, ordinary feature of the way people are already disposed to speak and think, so it is a bit surprising that critics of relativism are so disposed towards making this serious of a mistake.
3. Relativism is self-refuting
Some critics argue like this: “If you claim that morality is relative, then that statement is itself relative!” First of all, this would not be a self-refutation. So what if the statement itself was true in a relative sense? That wouldn’t make it false. More importantly, these critics mistakenly take relativism to be making a broader claim about what sorts of statements are relative than it is actually committed to. Relativism is a claim about first-order moral claims. What are these? These are direct claims about what is right or wrong, good or bad, prohibited or permitted, and so on (e.g., “Stealing is wrong”). It is not a position about the relativity of any other claims, including nonmoral claims (“That house is made of bricks”) or, critically, second-order or metaethical claims (these mean the same thing), such as “All moral claims are relative.” While this is a claim about morality, it is not a first-order moral claim, and the claim does not apply to itself.
Other critics will insist that if you claim that morality is relative that this statement presumes a nonrelative standard, so you are contradicting yourself. Again, this is a result of failing to understand that moral relativism is a position about first-order moral claims. The claim “all moral truths are relative” does not apply to itself. There is no contradiction in being a nonrelativist about the truth of relativism. Note another mistake here: these critics are simply assuming that if you say that all moral claims are relative, that you must mean this in a nonrelative way. How do they know this? Simple: they don’t. Critics of relativism often presume to know what proponents of relativism mean by what they say, when they aren’t in a position to do so.
4. It is impossible to live as a relativist
No it isn’t.
Such accusations are almost completely unsubstantiated and are typically supported by appeal to one or more other confusions and misunderstandings about relativism. It is not impossible to live as a relativist.
5. Relativism denies that there are moral truths, or that morality exists
Not it doesn’t. Relativism is a position about the nature of moral truth. It is a part of the position that there are (or at least can be) moral truths.
As far as the claim that morality doesn’t “exist”, this is ambiguous. Often critics mean something like the claim that “there are nonrelative, stance-independent moral facts.” Relativists do deny these exist, but firstly, relativists can believe there are stance-independent moral facts. Most don’t, though. More importantly, relativists don’t deny that people engage in moral judgment, that we have laws, institutions, and social norms that reflect moral principles and values, and so on. In other words, they think morality exists as a genuine psychological, social, cultural, religious, and more generally human phenomenon. These are very mundane respects in which morality clearly exists.
To accuse the relativist of thinking morality doesn’t “exist” is highly misleading without clarifying what this means. If all it means is that relativists deny that there are nonrelative moral truths, this is a trivial observation, and cannot serve as any substantive sort of objection. For comparison, this would be like objecting to atheism by saying that the position “denies the existence of God.” This is not an objection. It is literally just a description of what the position is. Just so, objecting to relativism on the grounds that it denies the existence of nonrelative moral truth is not a legitimate objection.
6. Relativism cannot make sense of moral disagreement
This objection has more going for it than others, but it is still misguided.
The argument runs roughly like this. Suppose you and a friend were arguing about the capital of New York. They insist it’s New York City, but you know it’s Albany. You disagree about what the facts are. It would make no sense to say that you disagreed, but neither of you held a different position on what the truth of the capital of New York.
Critics transpose this rationale over to morality. If you think stealing is wrong, but you run into someone who doesn’t think it’s wrong, you’re in the same situation as you’d be about state capitals: there is a stance-independent fact about whether stealing is wrong or not, so you disagree about what the truth is.
How can relativists make sense of this? When you say “stealing is wrong” this means that you disapprove of stealing. This is true. When the other person says “stealing is not wrong,” this means they don’t disapprove of stealing. This is also true. So there are no facts for you to disagree about. So does relativism make no sense because you don’t disagree about anything?
Not so fast. Are all disagreements disputes about what’s true? Have you and your friends ever wanted to order pizza, and had a dispute about what toppings to get? Maybe one friend hates mushrooms or another is vegetarian. You may go on to have a discussion about what toppings to get. It might even get a little heated. “You always insist on pepperoni!” One might consider such a dispute a…disagreement. And yet does anyone think that there is an objectively correct (or stance-independent) set of toppings to get? I suspect not. It’s really a matter of collective choice. And that’s just it. Some disagreements are not disputes about what’s true, they’re disagreements about what to do.
Such occurrences are common. If you go to buy a car or house, you will probably negotiate the price. The seller wants the highest price they can get, you want the lowest. You disagree about the price, and may argue about it. But this does not mean that there is a stance-independent fact about the “correct” price of the house or car. There is simply whatever price you’d both agree to.
The argument that relativism can’t handle disagreement relies on an overly narrow conception of “disagreement” that construes disagreements exclusively in terms of disputes about what the facts are, rather than a broader range of disputes that can include coordinating actions or coming to agreements. Indeed, we even call the resolution to conflicts about what toppings to get, or how much to pay for a car, and so on agreements.
Now, taking this back to morality, imagine a person who is opposed to abortion is out protesting abortion. A person who is prochoice confronts them, and they begin arguing with one another. Must we presume this would only make sense if they both think there is an objective (stance-independent) fact about whether abortion is right or wrong? No. Even if both are individual relativists, think about their overall set of attitudes:
Alex: Prochoice. Thinks abortion is not wrong. And wants there to be access to abortion.
Sam: Prolife. Thinks abortion is wrong. And wants to restrict access to abortions.
These people have different goals. And their goals directly conflict with one another. Why wouldn’t this be a good reason to argue?
As a final example, suppose you are confronted by a bully who demands your lunch money. Presumably you wouldn’t want to hand it over. You may argue with them or try to persuade them not to take it. But do you and the bully disagree about what the facts are? They want your money. You don’t want to give it up. Suppose you say “But what you’re doing is wrong”? …and they respond “Yea, so? I don’t care.” Now what are you going to do? You both agree on what’s going on, and both agree it’s wrong to take your lunch money. Note that you don’t disagree on any of the facts. So there’s no disagreement, right?
I don’t know about you, but this strikes me as quite strange. Just because you agree on what the facts are doesn’t mean you’d have no objection to them stealing from you. You may (and probably would) still wish to persuade them not to, by threatening to report them, pointing to a security camera and note there’d be evidence, call out for help, run away, and so on.
7. Relativism can’t account for moral progress
Yes, it can. Progress can be understood as progress relative to a goal, standard, or set of values. These goals don’t need to be objective duties or obligations you are required to follow independent of your subjective values or preferences. People make progress on personal goals all the time: in video games, in playing music or doing art, and so on.
In other words, we already think of ourselves as making progress in areas where there is no plausible set of stance-independent (objective) normative facts about what’s right, wrong, good, bad, etc. So why think this is somehow impossible for morality?
8. Moral relativism requires us to tolerate others, and even to tolerate intolerance
This might be true to some extent for agent relativism but it is not true for appraiser relativism.
9. Relativism is a lazy position people use as an excuse to justify their actions
It might be true that some people endorse relativism out of laziness or to excuse bad behavior. This is irrelevant to whether relativism is true. The mere fact that some people who hold a position may do so for questionable reasons does not mean the position is wrong. Some people accept what they’re taught in school without putting much effort in. They end up believing in the sun and the existence of bacteria and that water is H2O. This in no way indicates that any of these beliefs are false.
Also, one could argue that people appeal to moral realism to justify their bad behavior. After all, it’s a lot easier to justify your actions if you insist they aren’t your values, they’re just the moral facts, and you are obligated to obey them whether you wanted to or not.
10. The existence of widespread moral diversity proves relativism is true
It doesn’t. People disagree about all sorts of things: the existence of God, the causes of climate change, whether there was ever life on Mars, and so on. This does not mean that relativism about scientific claims or the existence of God are only true or false relative to different people’s preferences.
11. Moral relativism holds that morality is “made” rather than “discovered”
This is a bit misleading. Do you choose, create, or make your food preferences? I don’t. Simply because some fact about what you consider right or wrong depends on your moral values or those of your culture doesn’t mean this is a simple matter of choice.
12. Relativism can’t handle moral reformers
Yes it can (at least most forms of it can). First, reformers often attempt to convince their society to live by the moral standards it claims to adhere to in the first place. For instance, civil rights reformers may appeal to the fact that a surrounding culture oppressing them purports to believe in “equality” for all, or to the notion that we are all entitled to happiness, liberty, or opportunity. It is possible for the dominant cultural forces in a society to live in a way inconsistent with their own ideal standards, to come to realize this, and to change so as to live better in accord with their more fundamental moral values.
Second, individual forms of relativism have no problem accounting for reformers.
Third, appraiser relativism has no problem accounting for reformers. Reformers would be immoral relative to the standards of whoever they’re opposing but moral relative to their own standards.
13. Relativists must regard all moral standards as equally valid
This objection is strange because it seems to smuggle in the nonrelativistic presuppositions of the critic. It is true that a moral relativist will not believe there is any privileged point of view, i.e., a nonrelative view from which one could judge one moral standard to be “better” or “more moral” than another. But there is also no such vantage from which one could judge all moral standards to be equally good, either. There simply is no nonrelative standard from which to evaluate different moral standards at all.
Furthermore, when we say that another person’s perspective is “valid” this may imply that we are tolerant of that perspective and don’t oppose it. But relativists are not necessarily committed to tolerating moral standards that differ from their own. So this objection also carries implications that smuggle in other misunderstandings about relativism.
14. Relativism is a counterintuitive position almost nobody actually holds
This is an empirical claim. There is, at present, very little empirical evidence to support this claim.
15. Most philosophers are moral realists, while almost none are relativists, so relativists hold a position wildly at odds with what most philosophers think
This one is actually true. It’s just not clear this is a very good reason to reject moral relativism. While we might consider what most analytic philosophers think to be some evidence for a position, it is at best indirect evidence. Ultimately what matters is the overall quality of arguments and evidence for a view, not the mere fact that people believe it.
16. Relativists don’t really believe what they say
Some critics of relativism will insist that nobody sincerely believes relativism. This has nothing to do with whether relativism is true. In addition, this is an empirical claim, and those who make such claims rarely have any evidence to substantiate these claims. Most of the time, people who make these claims are not in a position to know whether any particular person or people in general don’t believe what they say. They can’t read minds! Rather, this is a way of criticizing the people who espouse a view without engaging with the view. What makes this approach insidious is that, while they can rarely substantiate these claims, it’s also hard to disprove them, as well. If a critic can successfully undermine trust in the relativist, they can threaten their position without offering any reasons to think relativism is mistaken.
17. Relativists readily abandon their position under pressure
Critics of relativism sometimes claim that people who profess to endorse the view easily relent or abandon these views with the slightest pressure. This is an empirical claim, and there’s no well established body of empirical data suggesting it’s true. This is, at best, based on anecdotal evidence, and at worst is simply something critics will make up or suppose is the case without being able to support this claim.
Even if it were true that people readily abandoned relativism under pressure, this does not mean relativism is false. Furthermore, we may wonder whether abandoning relativism is an indication that they were persuaded it was mistaken. It may not be. People care about their reputations and care about their grades. If a professor challenges a student espousing relativism, recanting their position (at least publicly) may be a way to preserve standing with a professor. Critics also often misrepresent relativism in ways that imply that you are a bad person if you endorse moral relativism. Publicly implying that someone has bad moral character if they believe something can incentivize people abandoning a view or at least no longer publicly supporting it if that person is more concerned with their reputation than with defending the view.
First, note that this has nothing to do with whether relativism is true. Second, this is an empirical claim about the psychology of individuals. It may or may not be true of any particular people that they don’t actually believe what they say they do, but critics are rarely in a good position to know this, since they can’t read minds.
18. Relativism is evil or if you endorse relativism, you are evil
People are entitled to think views are evil or that if you endorse a view, then you are evil. However, if they do make this claim, it’s often based on misunderstandings about relativism. Among other things, relativism is a descriptive position. A person who endorses that it’s true isn’t necessarily endorsing it as good or desirable. For comparison, endorsing the belief that cancer exists does not mean that you think cancer is a good thing.
19. Thinking things are right or wrong implies you’re not a relativist
Sometimes people will say that a person claims to be a relativist, but then goes on to judge other people’s actions or express views about what’s right or wrong. They then claim or imply that this is some kind of contradiction. It isn’t. For comparison, if you don’t think there are stance-independent truths about what food or music is good or bad, does this mean you are contradicting yourself if you say that you like a particular song or restaurant? No. This is absurd. The position that your moral claims express your value or your cultures values does not mean that you don’t have moral values, nor does it mean that you are prohibited from judging other people or cultures.
20. If you have a strong moral stance, this suggests you’re not really a relativist
Some people think that if you’re a moral relativist, that this indicates you should be less committed to your moral values. So if a relativist appears to be passionate about a moral issue, this is taken to indicate they’re actually a nonrelativist realist. This is not true. There is no inconsistency between being a relativist and having firm moral convictions.
21. Relativism treats morality exactly like our preference for ice cream flavors
This is misleading. While individual relativism does treat moral claims as something approximately like expressions of preferences, critics of relativism often imply that your moral claims are preferences, and your taste claims (like a preference for chocolate over vanilla) are preferences, then they are not only alike in that they are both expressions of preferences, but they are alike in other respects as well. I call this the overcomparison fallacy. The overcomparison fallacy occurs whenever a comparison is made between two things, such that have a particular thing or things in common, but others mistakenly think that they must have other things in common as well. For instance, suppose I say that lemons and the sun are alike in that both are yellow. It would be a mistake to say “You’re saying lemons are just like the sun? That’s ridiculous! The sun is much bigger and hotter!”
Likewise, the fact that a moral standard is a preference does not mean it is identical to food preferences in any other respects. Here are two important differences:
Scope: Food preferences are often preferences about our own conduct. They only concern what we eat ourselves, and have nothing to do with what others eat. In contrast, moral preferences often concern other people’s conduct. I don’t have a preference that other people enjoy the same food as me, but I do have a preference that they don’t lie or steal indiscriminately. Preferences can thus vary in scope, i.e., who they apply to.
Importance: If my ice cream preferences changed tomorrow, I wouldn’t care. But I’d care a whole lot if I were told that tomorrow I’d start finding it acceptable to lie and steal indiscriminately. I wouldn’t want to be that sort of person. Some values are more important to us. Some values are important enough to us that we prefer to retain those values no matter what, whereas others are incidental: they could differ, and we wouldn’t (given our current preferences) care very much.
Critics of relativism will often compare it to food preferences to scoff at the position. Yet when they do so by suggesting that the relativist thinks their moral values are as arbitrary or unimportant as simple taste preferences, or they think the relativist’s views make no sense because preferences only apply to oneself, they are mistakenly think that because you think moral standards and food preferences are both products of our own goals and values, that moral preferences and taste preferences are identical in every other respect as well. This simply isn’t true.
22. Conflating metaethical relativism with normative relativism
Some critics conflate metaethical relativism with normative relativism, which is the view that we should tolerate or respect other people or cultures with different moral standards.
23. Conflating metaethical relativism with descriptive relativism
Some critics conflate metaethical relativism with descriptive relativism, which is the empirical hypothesis that different individuals or cultures have fundamentally different moral values.
24. Subjectivism/Relativism imply that we are infallible
This objection is often directed against individual relativism (or “subjectivism”) in particular, which is the view that moral claims are made true by each person’s preferences and are thus relative to individuals rather than groups. However, the same objection could apply to other forms of relativism.
According to this objection, if relativism were true, we’d be incapable of making errors. This, critics insist, is absurd. The objection would go something like this:
P1: If relativism is true, we are morally infallible.
P2: We are not morally infallible.
C: Therefore, relativism is not true.
The reasoning behind the first premise is that if moral truth reflects whatever it is we prefer, or desire, or believe is morally right or wrong, then it’s not possible for us to make mistakes about what’s morally right or wrong. For comparison, one might think if you find that you prefer vanilla over chocolate, this isn’t something you could be incorrect about. All your judgments about what you prefer or disprefer simply determine what is true or false, and, as such, you need never worry about being mistaken. Even if you change your mind, whatever you change your mind to is now the truth.
Yet it is supposed to be very counterintuitive that we can’t be wrong about moral beliefs. We might think of times when we decided we were mistaken, or where we felt someone else was mistaken. Yet this would be impossible if people were infallible. Or we can imagine changing our minds about what’s morally right or wrong, or wondering if something really is right or wrong. This seems reasonable, but if we were infallible, wondering about such things wouldn’t make much sense. So, the reasoning goes, since it seems like we are fallible, relativism couldn’t be true.
This is not a good objection to relativism. The relativist has at least two main responses, but, taken together, they highlight how this objection derives what little persuasive force it has from misleading audiences.
Both of these objections first rely on being very clear about what the relativist is committed to. If you’re an individual subjectivist, you may hold the view that moral truth is determined by whatever our desires are. However, sophisticated forms of subjectivism often draw a distinction between instrumental and non-instrumental desires. An non-instrumental desire is a desire for something that isn’t a means to some further end; it is an end in itself. An instrumental desire is a desire that serves our non-instrumental desires; it is a means to an end. For instance, suppose you have the non-instrumental desire to be happy and avoid suffering. To achieve this end, you may need to go to the dentist, even though this would cause you some suffering. You may reason that since you desire less overall suffering in the long-term, it is best to suffer somewhat now. Going to the dentist is thus an instrumental desire, rather than something you desire for its own sake.
First, a relativist may point out that we could be mistaken about many of our non-instrumental desires. Why? Because we can be incorrect about what means would achieve our ends. Just because you have the goal of having a successful career does not entail that you know which decisions will realize that goal. A relativist could argue that it’s not that implausible that we could be infallible with respect to one or a handful of our most fundamental, non-instrumental values (e.g., a desire for happiness), but that we could quite easily be mistaken about just about every instrumental desire.
What this results in is a fairly modest claim to infallibility: I am not capable of being mistaken about my most basic desires, like a desire to be happy. This would result in rejecting “P2: We are not morally infallible.”
Second, subjectivism does not entail that we’re infallible even about our non-instrumental desires. It is consistent with subjectivism to believe we simply are capable of being mistaken about our own desires, including our non-instrumental ones. So another approach a subjectivist may take is to simply deny that we’re infallible. This would result in rejecting “P1: If relativism is true, we are morally infallible.”
However, the best strategy for relativists is to combine these two possibilities, draw attention to the vacuousness of the critic’s objection, and note how it is rooted in misleading audiences. Here’s how this works.
First, the subjectivist should ask the critic whether they think we are incapable of making mistakes about at least some of our desires. If the critic answers “Yes,” then the subjectivist can immediately not that the critic’s objection no longer works. After all, the subjectivist identifies moral truth claims with reports about their desires. If the critic things we are capable of being mistaken about our reports about our desires, then it would make no sense for them to think the subjectivist is committed to infallibility. After all, the subjectivist takes moral claims to be reports about their desires. If they’re fallible about the latter, then they are fallible to their moral claims.
If, on the other hand, the critic insists that we are infallible with respect to our desires, well, then, what’s so objectionable about the subjectivist position believing our moral judgments are infallible? Conditional on the belief that reports about our desires are infallible, then if our moral claims just are reports about our values then ipso facto our moral claims are infallible. The realist themselves will have undercut their own rationale for holding that this position is absurd, because they themselves are committed to the relevant form of infallibility.
The reason this argument appears persuasive to some people is that the critic fails to be explicit about what it is the subjectivist may think we’re infallible about. If we take some isolated claim:
Stealing is morally wrong.
…and are then told that the subjectivist believes we’re “infallible” about this claim then, insofar as “Stealing is morally wrong” is not regarded as a report about the speaker’s desires, this claim might seem absurd. In other words, it might appear absurd provided one doesn’t disambiguate what the statement means, allowing audiences to conflate the subjectivist’s analysis with some non-subjectivist analysis, and give the false impression that the subjectivist is suggesting we are infallible with regard to something other than reports about our desires. Suppose you translated the subjectivist’s moral claims into their explicitly subjectivist analysis:
I disapprove of stealing.
Is it that outlandish to say that people are infallible regarding such claims? Evidently not, or it would make no sense for the critic themselves to insist that subjectivism would entail infallibility: they themselves are implying that they think reports about our desires are infallible.
Now, why might one think we are fallible about our moral claims. Well, the subjectivist might think that we are fallible for various reasons consistent with subjectivism. But the main purpose of the criticism that subjectivism is absurd because it entails infallibility is a direct appeal to the audience’s hoped-for non-subjective moral intuitions. That’s it. Such objections ultimately amount to “subjectivism is false because non-subjectivism is true.” This is coupled with some misleading window dressing that conceals how empty such an objection is. It is not markedly different than saying that atheism is absurd because it denies the existence of God, but, since God exists, atheism is false.
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Great essay.
I've always found moral realism to be counterintuitive and the syllogistic arguments in favor of it unconvincing. Also, the recent growth in the popularity of notions such as so-called "effective altruism" strikes me as rather strange.
I don't have any formal training in philosophy (except logic & axiomatic set theory classes, if that counts), but I've read a bit about it, so I suppose I have some idea of what seems wrong about moral realism.
In particular there seems to be a semantic issue at play. Presumably, the existence of an epistemically objective morality means that there's some 'measure' by which actions or states of affairs involving people can be determined to be moral or otherwise.
I can't think of a better measure other than something like 'maximal goodness'. But what do we mean when we talk about goodness? It seems to me that people don't mean exactly the same thing when talking about goodness; i.e. the intension differs between speakers. 'Goodness' can in principle refer to any set of objects, properties, predicates, etc., and in general, people don't seem to be (indirectly) referring to the same objects, properties etc. when speaking of 'goodness', let alone in such a fine grained way as to allow them to have a shared definition of goodness. E.g. such and such action is preferred over some other action in literally *all* contexts or states of affairs.
So there doesn't seem to be such thing as commensurable goodness, in the sense that two competing notions of goodness are simultaneously maximally good/preferable for two different people *and* qualitatively different. Therefore, they can't be commensurable.
Furthermore, even if there were some universally good action that everyone hypothetically agreed on, it's not obvious to me that it could be non-arbitrarily justified: Why is it good? Because we all agree that it's good. I suppose this would be in a sense objective, but not exactly rational, which goes against what at least most moral realists seem to be getting at.
A stronger version of the criticism in #16 is that in the context of philosophy seminars, undergraduates often take a reflexive position of moral relativism because they don't have the conceptual tools and conviction at that time to justify the moral judgements that they continually make when outside the seminar room. They don't yet have a coherent metaethics and what they can say when forced to justify themselves is much less than what they can say in their day-to-day life. It is no surprise then (as seen with #15 and #17) that many of these students desist after they becoming better at philosophising, just as they commonly stop being solipsists and radical sceptics about knowledge.
Or another way to put it, is that moral relativism as actually commonly encountered is usually less coherent and strongly held than the kinds of considered relativisms that people like Lance Bush would argue for. Lance is right that this isn't an argument against the best versions of the theory, though it must be admitted that people commonly encountered espousing relativism don't tend to hold those versions.