Here’s Mike Huemer’s first set of responses to me and you.

About Bryan’s Comments

Thanks to Bryan for his fair and helpful comments on part 1. There isn’t much that we disagree about. But here are some thoughts about Bryan’s comments.

1. Philosophical progress:

It’s fair to say that philosophy makes slower and less impressive progress than the natural sciences, or even economics. (But not less than the other humanities and social sciences.) And there are at least some 2,000-year-old issues that are still being discussed, such as the problem of universals.

Consequentialism vs. deontology isn’t one of them, though. I don’t see any discussion of that in the ancient philosophers. You can maybe trace the consequentialist/deontological debate to Hume and Kant, but they are not clear about the issue. Anyway, there is important progress on that issue, as hopefully will emerge from chs. 14-15 later: Most of the arguments I discuss there (which I consider the most important arguments) about consequentialism and deontology are of recent provenance, from the last century at most.

Bryan wants to suggest, I think, that some of the philosophical progress we’ve seen is based more on social conformity than arguments. He then mentions that one could readily construct arguments for the wrongness of homosexuality. However, it remains plausible (to me) that these would be bad arguments, and that the poor quality of the arguments helps to explain why they are not popular. Social conformity can explain any given individual’s beliefs, but it doesn’t explain why the attitudes of society change in a particular direction.

I don’t claim that all philosophical progress is due to evaluation of arguments, though. Much of it is about progressively overcoming biases that previously distorted our intuitions or caused us to look for arguments to rationalize those biases.

2. The terms “valid” and “sound”:

A better terminology was suggested by my logic professor at Berkeley (Ernest Adams). He used “factually sound” for arguments that have true premises, “logically sound” for arguments that have premises that entail their conclusions, and “sound” (without a qualifier) for arguments that are both logically and factually sound. These terms make the right distinctions and sound like what they mean.

3. The instrumental value of truth

Bryan is correct that at least some false beliefs can be useful for attaining your goals and getting along with other people. But I think there are many cases where false philosophical beliefs prevent you from attaining your goals. They can also cause you to act imprudently or immorally (whether or not you are attaining your goals).

For instance, if you falsely believe in God, then you might waste your life serving a non-existent God. Or, less extremely, you might just give up a bunch of good stuff in life because of your religion.

About getting along with other people: If you form false philosophical beliefs, then in some cases you may have conflicts and ruin relationships with people who are actually right (which I assume you don’t want). E.g., suppose you believe (i) racism is the most horrific, unforgiveable evil, and (ii) anyone who says that all lives matter is a racist. (I guess those are philosophical beliefs.) Then you’ll have a hard time getting along with people who say that all lives matter. Now, if beliefs (i) and (ii) are actually true, then I suppose it’s good that you’re getting those people out of your life. But if they are false, then it’s probably bad.

On one level, the person who has those beliefs would “satisfy their goals” – e.g., the goal of expressing blind loyalty to their chosen social faction. But that’s sort of an unconscious goal. On a more conscious level, they don’t want to be being an asshole who makes a mockery of the concept of justice by condemning those who are honest and just. Yet their false philosophical beliefs lead them to do that.

4. Being objective

I agree that there’s a distinction between the strongest arguments for opposing views and the most popular arguments. I didn’t make that clear in the text. I also agree that one should generally try to address both of these things.

5. Subjective claims

The advice to avoid subjective claims (and anecdotal claims, and the advice to use weak and widely shared premises) is only a rule of thumb. Other things being equal, it’s better if you use more objective premises, rather than more subjective ones. So that’s compatible with saying that some subjective premises are acceptable.

Is the rule of thumb about subjective claims redundant? I don’t think so. Consider Caplan’s two examples:

(Subjective)        Being mean to children is worse than being mean to adults.

(Objective)        Communist governments murdered millions of people.

The second one is a better premise for an argument than the first one, right? It looks to me like that is best explained by the fact that the latter is more objective.

6. Relativism & skepticism

I think skepticism is more popular than relativism among philosophers, probably because skepticism is less incoherent. However, neither is a popular view among philosophers. The great majority of epistemologists who talk about skepticism think that the goal is to explain what’s wrong with it. Only a few recent philosophers are known for defending skepticism. That includes Keith Lehrer at one point in his career, Barry Stroud (who was at UC Berkeley when Bryan and I were there), and … almost no one else.

Moral anti-realists, however, are quite common. It appears that non-cognitivism (or “expressivism”) is the most popular view in metaethics.

Caveat: My knowledge is mainly of the dominant culture in academic philosophy, which is that of philosophy departments at R1 universities. Here, Richard Rorty is hardly ever discussed. However, I am under the impression that lower-ranked universities have many more Continental philosophers, which would include more relativists and subjectivists.

About Comments from Readers

Here are some things said by readers in the comment thread, and my responses to them.


I was taught that an argument being valid meant something more like “If the premises are true, then it’s impossible for the conclusion to be false.” That [is], the definition of validity depended on the idea that the conclusion must follow from the premises.

Both of those are also commonly stated in logic classes and textbooks. That is, three definitions are commonly given:

  1. An argument is valid iff: the conclusion follows from the premises.
  2. An argument is valid iff: if the premises are true, then the conclusion must be true.
  3. An argument is valid iff: it’s impossible that all the premises be true and the conclusion be false.

Often, all three of these appear in rapid succession in the same book, and they are always treated as synonymous. #2 is supposed to be an explanation of #1, and #3 is supposed to be an explanation of #2.

Later in the logic class, students will be told (as another commenter noted) that if-then statements can be analyzed as follows:

If A then B = (~A v B) = ~(A & ~B)

So that makes sense of how definition 3 could be equivalent to definition 2. The only problem with this is that most philosophers think the above definition of the conditional is wrong. There are many examples that seem to show this, and logic professors are well aware of that fact. That’s why, in both my undergraduate and graduate logic classes, the professor expressly acknowledged that the above was a poor account of the meaning of “if-then”. In spite of this, they go ahead and assume it when talking about the definition of “validity”. Pretty annoying, eh?

Btw, there were a couple of logic mistakes in the comments …


That means we can restate your definition (“If the premises are true, then it’s impossible for the conclusion to be false”) as this disjunction: “Either it is impossible for the conclusion to be false, or the premises are false.”

That’s a mistake; the modal operator has to take wide scope (over the whole rest of the proposition). So it should be: “Necessarily, [the conclusion is true, or at least one of the premises is false].”


To make the definition “better,” you need to replace if/then with if and only if

This doesn’t make the definition better. Suppose we say:

  1. An argument is valid iff: necessarily, the premises are true if and only if the conclusion is true.

Then you get arguments like the following being valid: “7=7; therefore, the shortest path between two points is a straight line”, and the following would be invalid: “The sky is blue; therefore, the sky is colored.” If you take out the “necessarily”, then you get the following being valid: “The sky is blue; therefore, kittens are furry.”


In common English, saying “this begs the question” sounds a lot like “this makes me want to ask such and such,” which is how it is often used. But in this case, instead of dunking on the philosophical term, you dunk on the common usage. What’s different in this case?

Philosophers invented the expression “beg the question”. It derives from a practice in ancient and medieval philosophy, in which you would try to prove a proposition by the Socratic method. You would ask another person questions, then try to derive the desired conclusion from the other person’s answers. The other person was supposed to answer according to their actual beliefs. In this game, there was a rule that you could not just straight out ask the person what they thought of your intended conclusion. E.g., if you’re trying to prove that the soul is immortal, you could not just say, “Is the soul immortal?” In medieval philosophy, that was known as the error of petitio principii, asking for the initial thing (i.e., asking the other person for the thing you initially set out to prove). “Begging the question” then arose as poor translation of “petitio principii”.

Now, the more recent usage of the term arose due to people who had heard the phrase “beg the question” without knowing what it meant, so they apparently just assumed that it meant “raise the question” (even though this assumption made no sense given the context in which they’d heard the phrase). Then they apparently decided that they would start saying “beg the question” instead of “raise the question” because they thought they were being more sophisticated by using a less common phrase, when actually they were just being ignorant.


Fashionable discourse about racism often commits the fallacy of affirming the consequent. ‘If an institution is racist, it has negative disparate impact on Blacks. Institution A has negative disparate impact on Blacks. Therefore, A is racist.’

I think the people you are talking to are not saying that. A more charitable reading is that the first premise is supposed to be “If an institution has a negative disparate impact on blacks, then it is racist.” The SJW’s would also claim that you’re mistakenly thinking only of personal racism and not considering “institutional racism” or “systemic racism”.


Huemer seems to distrust the media for even direct observations. […] [F]or every direct observation by the media, what they say is probably true. I would be shocked if Huemer denies this, and it appears he did.

I’m not sure what the commenter meant by “direct observations”. News media people rarely directly observe what they’re reporting on. Anyway, I don’t think that they commonly completely invent stories. I think there is generally a real event that resembles what they’re talking about. However, I think that the general, politically relevant impression that you take away from the story is just about completely unrelated to the impression that you’d get if you had direct, personal knowledge of the story. E.g., if two people have a dispute, the media might report a bunch of things about the dispute that are true, but the impression you get from the story about who is in the right will have no relation to the conclusion you’d draw if you knew all the facts.

In the NPR case: They didn’t exactly lie, but they gave an extreme spin. Saying that a witness “recanted his testimony”, when the witness changed his claims about some incidental details of the case, is not exactly a lie. It’s just incredibly misleading, since, in the context, it suggests that what the witness recanted was the claim that the defendant was guilty, or something closely related to that.

That’s my impression of how the media work. They don’t usually outright lie or fabricate factual details. But they don’t mind spinning the story so severely that you’d draw conclusions 180 degrees from the truth about the things you actually care about.


At least to me, it is not clear that changes in philosophical arguments against slavery and homophobia, have brought about societal changes. It might very well be the other way round.

I’m confident that slavery was abolished due to the actions of abolitionists, and the abolitionists were driven by their belief that slavery was unjust. And they thought it was unjust due to good arguments (albeit perhaps pretty simple arguments). What’s the alternative view? Would it be that the abolitionist movement was impotent? Or that the abolitionists had some non-moral motive? Or that their beliefs were unfounded? Or maybe they were just intuitive, not based on arguments?

Another question is whether professional philosophers were the source of the arguments. Of course, you don’t have to be a professional philosopher to be moved by philosophical arguments or to contribute to social progress, and most of the people who did those things were not professional philosophers. I expect that professional philosophers have had a relatively small role there.

But here is an example involving a professional philosopher: The contemporary animal welfare movement was started mostly by philosopher Peter Singer, the author of Animal Liberation. Now, what is actually going to end factory farming is the development of synthetic meat and plant-based meat substitutes. But the development of those products is motivated by philosophical arguments – the founders of organizations like Beyond Meat, Impossible Foods, and the Good Food Institute are animal welfare and environmental advocates, and that’s what drove them to found their organizations. So that’s an example of how philosophy has a big impact on society.


Maybe it is plausible that there is an objective humor, but it is always directly sensed rather than a consequence of constructing a chain of arguments from intuitions.

My main problem is that I just have no idea what this objective humor is supposed to be. I have no idea what funniness is, if it doesn’t have something to do with amusement, and I have no idea what amusement is if it’s not a reaction in observers.


‘Covid is a deadly disease. B is an uncertain treatment for preventing Covid. If you believe in Treatment B, then you must not believe Covid is a deadly disease.’ Would that be an example of Denying the Antecedent?

I don’t see how. Denying the antecedent should have the form: “If A then B; ~A; therefore, ~B.” The above has the form, “A. B. If C then you don’t believe A.”


Any ‘best practices’ tips  for analyzing an argument?

I guess I would suggest looking at books on mistakes that people make (including my own book, and maybe some of the psychology literature on heuristics and biases), and just getting more experience reading arguments, people’s objections to them, and people’s replies to objections.


here is another story, from roughly 20,000 years ago. It involves 2 tribes, the Pushovers and the Pigheads. They each had their Creative Genius. One time, the Genius from the Pushover tribe comes into the cave with a burning log and says “Look, we can control fire! We can use it to cook our food, have light to work inside our cave, and stay warm during winter!” The others objected.

If this was a tribe of Pushovers, why wouldn’t they all say, “Okay, sure, whatever.”? And wouldn’t the tribe of Pigheads refuse to ever try the fire? Then the story would have the opposite of your ending: the Pushovers would prosper and the Pigheads would fail. Anyway, here’s another story:

The Pighead Foragers tribe decides to go look for food. They see a valley that looks auspicious, so they quickly form the belief that there will be lots of food there. They go into the valley but can’t find any food. Because they are Pigheads, they refuse to admit that they were wrong, and they keep searching in that valley until they all starve to death. The end.

That’s an illustration of how dogmatism is bad for you.