One of the skills of critical thinking is to understand logical fallacies – to recognize them in your opponent’s arguments and not rely on them yourself. But it’s easy for beginners to get caught out by them – to misunderstand a fallacy and call it out in error. You certainly need to be sure you understand them before you make a fool of yourself. Nowhere is this more evident than in the link Orac sent me to a post on Hank's "You Bet Your Life" blog. Hank doesn’t think HIV causes AIDS, and in his post AIDS Inc: Common Logical Fallacies he lists what he thinks are the logical fallacies employed by what he calls the “AIDS bunglers”. As an educational exercise I thought I should point out Hank’s errors, which are threefold:
- Calling fallacies that aren’t
- Calling the wrong fallacy, and
- Stating Straw Man versions of his opponents’ positions, and calling them fallacies.
For brevity I’m going to refer to the idea that HIV causes AIDS as the “HIV theory”, and its proponents “HIV theorists”. I will refer to the people who disagree with this as “dissenters”. In this post I’m not going to discuss specific evidence that shows HIV does or does not cause AIDS – I’m going to focus solely on Hank’s misuse of logical fallacies.
If you don't believe that HIV causes AIDS, well, you suck.
If that was all the HIV theorists had to offer, this would be ad hominem. However, they don’t rely on ad hominem, they rely on the evidence, and if evidence is presented to support your position, you are not relying on fallacious logic. Which brings us neatly to Hank’s next point:
Appeal To False Authority:
The NIH has a great government website, which explains why HIV Causes AIDS
This is not an Appeal To Authority. If the claim was just “the NIH says HIV causes AIDS”, this might be an appeal to authority. But here’s the thing: the actual article Hank links to is a summary of the evidence that HIV causes AIDS, plus rebuttals to the many “HIV does not cause AIDS” myths. Someone could debate these evidences if they wanted to, but they can’t deny that the website does, in fact, list detailed evidence that HIV causes AIDS. Therefore, the website is not relying on the authority of the NIH but on the evidence it lists. Citing evidence is not an appeal to authority, and so citing this website is not fallacious.
This is a classic example of someone who has heard the term “Appeal To Authority”, but has not understood it. If an “authority” lists evidence, it is not fallacious to cite it.
Appeal To Emotion:
Look, millions of poor Africans are gonna die, if you don’t immediately start believing that HIV causes AIDS!!!
That would be an Appeal To Emotion, but the HIV theory relies on evidence not on this Straw Man Hank has created.
Appeal to Fear:
Did you see what we did to Duesberg? If you don't accept that HIV causes AIDS, we will strip away your funding and ostracize you. Now, get smart, will ya?
I’m not sure why this paper from 1987 is cited – it doesn’t really say what anyone “did to Duesberg”, and if this is all that happened in 19 years is this really anything to fear? In any case, Duesberg’s credibility has been damaged because the preponderance of evidence supports the HIV theory and not Duesberg’s largely unsupported claims, not because anyone “did” something to him.
Appeal To Force:
If you don't agree that HIV causes AIDS, we will call CPS and take away your children.
The cited article suggests that children are being experimented on in violation of medical standards, but nowhere in the article is it suggested that the children were taken away because their parents doubted that HIV causes AIDS. Hank’s citing this article is really itself an Appeal to Fear, or an Appeal to Emotion.
Appeal To Majority:
C’mon, everybody’s wearing a red ribbon, why not you?
This is hilariously absurd. The link is to one of Hank’s earlier posts which describes a Seinfeld sketch - the one where Kramer is ostracized for not wearing a red AIDS ribbon. I’m not making that up – check the link. It takes some serious chutzpah to write an article about how your opponents use logical fallacies, and as evidence for this you cite the script of a TV sitcom. I’m not sure exactly what fallacy that would be (argument from authority?) – but it is certainly ludicrous.
The funny thing is that even in the sitcom, Kramer is not saying HIV doesn’t cause AIDS, he just doesn’t want to wear a ribbon – which makes Hank’s citing it a False Analogy too. I think it is probably also a non sequitur, but I’m open to other suggestions of what fallacies Hank is relying on here.
Appeal to Novelty:
Yeah, I know that retroviruses historically haven’t been show to kill cells, but this is a NEW retrovirus from a Chimpanzee in Cameroon via the Castro!
I don’t ever recall any HIV theorists relying on that Straw Man argument.
Appeal To Numbers:
Thousands of scientists think that HIV causes AIDS, why not you?
No. An Appeal to Popularity (as I prefer to call it) is something like “millions believe homeopathy works, so it must work”. But those millions are being fooled by the placebo effect amongst other things, which is why the number of people who believe it is irrelevant. But the “thousands of scientists” are all looking at the evidence.
Appeal To Tradition:
Traditionally, viruses are very bad things, causing many different ailments, why not this virus, too?
Another rather silly Straw Man of the HIV theory. Did anyone ever seriously make this argument for the HIV theory?
Argumentum Ad Nauseum:
HIV causes AIDS. You’re a Dissenter. HIV causes AIDS. You’re a Dissenter. HIV causes AIDS. You’re a Dissenter. HIV causes AIDS. You’re a Dissenter. HIV causes AIDS. You’re a Dissenter. HIV causes AIDS. You’re a Dissenter.
That might be Argumentum Ad Nauseam (note the correct spelling) if that was all that was offered, but (again), HIV theorists have evidence too.
Begging The Question:
AIDS is the disease that is caused by HIV, the virus that causes AIDS.
Again, if that was all that was offered it would be circular reasoning, but there is that pesky evidence too.
Burden Of Proof:
Can you prove that HIV doesn’t cause AIDS?
Since the evidence that HIV causes AIDS is pretty strong and widely accepted by scientists in the field, I think the burden of proof is back in the dissenters’ camp to show evidence for their alternative.
Have you stopped beating your wife while denying that HIV causes AIDS?
That doesn’t even make sense. Anyway, another Straw Man.
Either you accept that HIV causes AIDS or you're responsible for killing millions of Africans.
This doesn’t really make sense as a false dilemma. A false Dilemma is where two alternatives are held to be the only options, when in reality there exist one or more other options which have not been considered. But “accept that HIV causes AIDS” and “be responsible for killing millions of Africans” are not really alternatives, are they? It’s more an appeal to consequences, but even that doesn’t really work. Either way it’s another of Hank’s Straw Men.
Since HIV is found in all cases of AIDS, obviously HIV must cause AIDS.
If there was no known mechanism for how HIV causes AIDS, or if there was no evidence for the HIV theory, he might have a point.
Look, highly credentialed scientists have usually got it right in the past, so I just know they got AIDS right this time!
No, this is not a Gambler’s Fallacy. The Gambler’s Fallacy refers to random activities, such as coin tossing. For example, if you just tossed a coin three times and got three heads, a gambler’s fallacy would be to say the next toss would be more likely to be tails (since you just got three heads in a row). Of course, the probability of getting heads again would still be 50% since a random event is not less likely to occur because it recently happened. But science isn’t “random”. The reason the “highly credentialed scientists have usually got it right in the past” is not due to randomness – it’s due to the reliability of the scientific method. It is not fallacious to say that scientists are likely to be right, unless you can specifically explain why they are likely to be wrong in this case (which Hank hasn’t done).
Guilt By Association:
You know who else doesn’t believe that HIV causes AIDS?
*(insert pictures of Nixon, Mbeki, Kary Mullis here)*
Would be ad hominem, if the above was the argument presented. Again, it’s one of Hank’s Straw Men.
HIV causes AIDS, because if not, that means we've been lying to people all these years.
More of an Appeal to Consequences, actually. Or perhaps a false dilemma. And if the above was the argument it would be fallacious. But again, there is the evidence.
No True Scotsman:
Argument: "No Scientist questions whether HIV causes AIDS
Reply: " Dr. Kary Mullis questions whether HIV causes AIDS."
Rebuttal: "Ah yes, but no true scientist questions whether HIV causes AIDS.
That would be a NTS, except that I don’t think anyone says "No Scientist questions whether HIV causes AIDS”. After all, we know Duesberg questions it, and he’s a scientist. Another Straw Man.
Post Hoc/False Cause:
Since we’'ve started pumping people with AZT and other toxic drugs, AIDS deaths have decrease 62%. Therefore, HIV causes AIDS.
No, this is not a Post-Hoc fallacy. If there was no theoretical mechanism for how AZT works, and we just randomly noticed that AIDS deaths decreased in correlation with AZT, this would be a post hoc fallacy. But we do have theories of how AZT works, and recipients of AZT and other AIDS drugs have been monitored very carefully since their introduction to determine the results. It is not Post Hoc fallacious reasoning to note that people got better after taking drugs designed to make them better – if it were we would never be able to trial any new drug or therapy, and there would be no point ever to double-blind studies.
Well, you say that to prove HIV causes AIDS, requires extraordinary evidence, because it's an extraordinary claim. Well, we’d like to note that "Extraordinary claims demand extraordinary evidence" is itself an extraordinary claim.
Another Straw Man. Extraordinary claims do require extraordinary evidence, but no one claims that this, is itself an extraordinary claim. In any case, I think the HIV theorists have provided the extraordinary evidence – it is the dissenters who don’t have the evidence.
If you don't accept that HIV causes AIDS, you will do poorly in class, drop out of school, commit crimes, go to prison, and die of AIDS.
Not really a slippery slope; more an Appeal to Consequences, I would have thought. Either way Hank is making another Straw Man.
Just to be clear on this Straw Man business – I’m not claiming that no one ever said anything like the things Hank is claiming; I’m saying these Straw Man arguments Hank is putting forward are not the main arguments put forward by the scientists who support the HIV theory.
Reading Hank’s post I was reminded of something Jason Rosenhouse wrote recently:
… it has never once happened in the history of science that a theory achieves mainstream status, only to fall apart when a clever outsider notices a simple logical oversight.
Of course Jason was writing about Ann Coulter’s supposed “disproval” of evolution, but it occurred to me that it could just as easily apply to AIDS dissenters. They have a lot in common: a poor understanding of science and logic, combined with a religious need for the orthodox science to be wrong. With HIV/AIDS, as with (say) evolution and global warming, you don’t have to understand all the evidence to accept that the orthodox view is probably correct - you can get a pretty good idea just by looking at the position the majority of peer reviewed science is supporting. That doesn’t mean the orthodox position is definitely 100% correct – all science is provisional and anyone can challenge the orthodoxy if they have compelling evidence. But challenging orthodoxy is an extraordinary claim, for the good reason that the orthodoxy is already supported by extraordinary evidence. To overturn this you need even more extraordinary evidence to the contrary, and this misnamed list of fallacies isn’t it.