ad hominem, no true Scotsman, and arguments from authority

I just thought I'd write a quick note on the ad hominem and no true Scotsman fallacies, because I've noticed a lot of people being confused by them.

A lot of people confuse an insult for an ad hominem fallacy.  Ad hominems do often involve insults, but they don't necessarily, and not all insults are ad hominems.  If I said that you're a man, and therefore your opinion on abortion cannot be trusted, I'm using an ad hominem argument, but I'm not insulting you.  Calling you a man is not a criticism.  It's just an observation about you that is irrelevant to the soundness of whatever argument you have for or against abortion.  If you gave me an argument against abortion, and my reaction was to call you an idiot, that is not an ad hominem.  That's just an insult.  It only becomes an ad hominem if I say something like, "Since you are an idiot, you must be wrong about abortion."  An ad hominem is when you point to something about a person that is irrelevant to the soundness of their argument or the truth of their point of view, but you offer it as evidence against their point of view or the soundness of their argument.

A lot of people lately have been accusing Bart Ehrman of the No True Scotsman fallacy, but they are confused about what the fallacy is.  A fellow named Jason Goertzen had this to say in the comment section of Ehrman's piece called "Acharya S, Richard Carrier, and a Cocky Peter (Or: "A Cock and Bull Story")":

I lost count of the number of times you felt the need to point out that "no serious scholars" (a variant of the No True Scotsman fallacy, given how strenuously you define what you mean) believes x, or y; to the person who wants to be convinced, this isn't adequate.

Ehrman doesn't dismiss people as being serious scholars because they deny the existence of Jesus.  A fellow named Steve Bollinger said on his blog:

But it's not merely that Ehrman declares the discussion to be over; he states as well, on no firm basis whatsoever if you ask me, that no accredited professor in the Western World "who teaches New Testament or Early Christianity or even Classics" disagrees with him.  That already puts Ehrman into no-true-Scotsman territory.

Ehrman doesn't dismiss these people because they deny the existence of Jesus, so this is not the No True Scotsman fallacy.

Here is an illustration of the fallacy:

Jim:  No Scotsman would ever tell a lie.

Bob:  But Dan is a Scotsman, and he tells lies.

Jim:  Dan is not a true Scotsman.

Bob:  Why do you say that?

Jim:  Because no true Scotsman would ever tell a lie.  The fact that he tells lies proves that he's not a true Scotsman.

The No True Scotsman fallacy trades on a distinction between an analytic truth and a synthetic truth.  If being honest were part of what it meant to be a Scotsman, then when Jim says no Scotsman would ever tell a lie, he's not making a synthetic statement.  He's making an analytic statement.  He's giving us part of the definition of a Scotsman.  If he's right, then Bob is stating a contradiction.  Saying that Dan is a Scotsman who tells lies is equivalent to saying, "A person who tells no lies, actually does tells lies."

The No True Scotsman fallacy only comes into play when statements like "No Scotsman would ever tell a lie" is a synthetic statement.  Jim isn't saying that it's part of the definition of a Scotsman that they don't tell lies.  He's saying something that happens to be true about Scotsmen, but it's not a necessary truth.  It's not part of the definition.  In fact, it's possible that a Scotsman could tell a lie even if none ever have.  In that case, Jim is committing a fallacy when he objects to Dan being a Scotsman merely on the basis that Dan tells lies and no true Scotsman tells a lie.  If you reason that way, then you're basically just dismissing the possibility of counter-examples to your claim.  Jim is treating a synthetic statement as if it were an analytic statement.

In the case of Bart Ehrman, he has claimed that most of the mythicists who deny the existence of  Jesus are not credentialed scholars.  For that, he is being accused of committing the No True Scotsman Fallacy. But to be guilty of the No True Scotsman fallacy, Ehrman would have to be saying that the reason these mythicists are not credentialed scholars is because they deny the existence of Jesus.   It would have to go something like this:

Bart:  No credentialed scholar of the New Testament would ever deny the existence of Jesus.

Robert:  But D.M. Murdock is a credentialed scholar, and she denies the existence of Jesus.

Bart:  The fact that she denies the existence of Jesus is precisely why I say she is not a credentialed scholar.

But that is not how Ehrman has been arguing.  Rather, he's been saying that she and most mythicists are not credentialed scholars because they do not have advanced degrees in the relevant areas, they are not published in peer reviewed academic journals, and they don't hold teaching positions at any colleges or universities on the relevant subjects.   A person might still accuse Ehrman of the No True Scotsman fallacy on the basis that every time somebody comes up with a counter-example, Ehrman changes his definition of what counts as a "credentialed scholar" so as to dismiss the counter-example.  But so far, to my knowledge, this has never happened.  These are not arbitrary criteria for what counts as an expert meant to exclude people who deny the existence of Jesus.  I remember when I had to write papers in college, pretty much all of my professors, whether in philosophy or history, demanded that our secondary sources be academic.  I remember one of my philosophy professors specifically said that we could not quote from a web page called "Joe's Automotive and Existential Philosophy."  Credibility in our sources mattered, and we had to use scholarly sources.

But let's suppose it turns out that Ehrman argues something like this:  Since most mythicists are not credentialed scholars, their opinion on the existence of Jesus is false, or their arguments against the existence of Jesus are unsound.  If he argues that way, then he's not committing the No True Scotsman fallacy.  Rather, he's committing an ad hominem fallacy.  A person's credentials are irrelevant to whether their point of view is true or their argument is sound.

A person's credentials are not completely irrelevant in this whole debate, though.  They are relevant only in cases of arguments from authority.  If you cite Richard Dawkins as an authority on the cosmological argument, then that is a fallacious appeal to authority because he has no expertise in the subject.  But if you quote Richard Dawkins as an authority on the subject of gene replication, then that is not a fallacious appeal to authority.  He actually is an expert in the subject of biology.  An appeal to authority is only a fallacy if the authority you appeal to is not an expert on the subject you cite him on.  If somebody is actually an expert in the subject of the New Testament or historical Jesus studies, then their opinion is relevant.

But some people will claim that any appeal to authority is a fallacy since it's the argument the authorities use that count, and not the mere fact that they are authorities.  I vaguely remember Robert Price going so far as to say there are no authorities when it comes to the historical Jesus.  I think he may have a point.  The opinions about Jesus in academia are diverse.  If the experts disagree, then it's fallacious to quote one of the experts to support a view that's actually controversial among that expert's peers.  On the other hand, there are a handful of things about Jesus for which there is a strong consensus among experts, e.g., he was baptized by John the Baptist, he had disciples, he preached about the kingdom of God, he used parables in his teaching, he was known for being a miracle worker, and he was crucified on the orders of Pontius Pilate.

In his recent podcast, Price said he had written a pieces called "Paradigm Policemen," where he criticized Bart Ehrman for vociferously defending the status quo.  Price made what I thought were some good points, but I think he went too far.  It is true that the mere existence of a consensus does not mean the consensus is right, and it's true that if we stick to consensus and never dare to challenge it, that we stifle progress.  After all, we can point to moments in our history when paradigms were overturned, often with much difficulty.  The Copernican Revolution is one of the most famous examples.  Price thinks it's a mistake for Ehrman to criticize mythicists merely on the basis that they are going against the current consensus on the existence of Jesus.  I think he's right, but on the other hand, I do think consensus counts for something.

Most of us are not experts in any field.  We're armchair theologians, armchair philosophers, armchair historians, armchair biologists, etc.  Most of our education comes from reading books, not doing our own research.  Many of us read books and think that counts as doing research.  But really, for the majority of our educations, both formal and informal, we rely on the findings of experts.  If consensus counted for nothing, then our educations would be worthless.  We could read a dozen books on the historical Jesus or evolution and still not know anything.

Sometimes, if you're writing on a historical point of view, it is too tedious to spell out the arguments for every little piece of evidence you bring forth.  Even scholars, when writing on the historical Jesus, will appeal to studies that other scholars have done on some small point, then use that small point as part of their case for their point of view.  It helps when there's a consensus because then you can use that piece of information in your case without too many people raising objections about it.  If consensus didn't matter, or if expert opinion didn't matter, then we would never be able to build on information discovered by other people.  Everybody who wrote on any subject in history or biology would have to start from scratch.

I think we should lean in favour of the experts, especially when there's a consensus, but we should not do so dogmatically.  We should be willing to go against consensus when we ourselves have done enough research or have been adequately persuaded to hold a differing opinion.  I can't tell you what's adequate. You have to judge that on a case by case basis, and in a lot of cases, it's subjective.  But I don't think we should fault mythicists merely on the basis that they are in the minority.

However, I think it is appropriate to point out that there is a strong consensus among experts on the existence of Jesus to people we run into on the internet because most of them haven't done any research.  They've watched Zeitgeist and just took their word for it.  If they're going to just take somebody's word for something, then they should take the word of those who are actually credentialed scholars.  It's appropriate to bring up the consensus for a lot of those people because they may just not know any better. Two or three years ago, I got an email from somebody who had just seen Religulous with Bill Maher.  Apparently, Maher had brought up the whole myth thing, which was completely new to the person who emailed me.  She did a quick google search, found a short article on Religious Tolerance about Jesus and Horus, and was convinced.  This was all new to her, and she wanted to see what I'd think.  I think she half expected me to be surprised.  I think it was perfectly appropriate for me to point out that almost every single New Testament scholar or historical Jesus scholar believed that Jesus really existed, and that it wasn't even a serious debate in academia.

I'm rambling, aren't I?  Okay, I'l stop.