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As I’ve sure you’ve heard by now, Dr. Stella Immanuel has claimed that we don’t need to wear masks, or really take any precautions against the spread of COVID-19, because there is already a cure: hydroxychloroquine, zinc, and Zithromax.
To be clear, this is absolutely false. But the video was viewed over a million times before it was taken down, and many people believed her simply because she is a medical doctor.
To debunk her claim, websites like PolitiFact have not only proven that what she said was just outright false, but drawn attention to a host of other bizarre medical claims that she has made—like that
“gynecological problems like cysts and endometriosis are in fact caused by people having sex in their dreams with demons and witches, [that] alien DNA is currently used in medical treatments, … that scientists are cooking up a vaccine to prevent people from being religious, [and] the government is run in part not by humans but by “reptilians” and other aliens.”
This likely has anti-mask advocates crying foul. Isn’t this a personal attack, an ad hominem? “What she says about other topics has no bearing on what she says about this one.”
Except, actually, it does.
The ad hominem fallacy applies when you attack the person giving an argument, rather than the argument itself. Now an argument is a collection of statements, one of which (the conclusion) is supposed to follow from the others (the premises). And arguments are good if they have a valid or strong structure and their premises are true. Neither of those things is determined by the character of the person giving the argument. Often, the structure can be evaluated mathematically; and a premise is true if it corresponds to the way the world is. And if it does, it still will, regardless of who states it. So the character of the person giving an argument is often irrelevant to its quality.
However, if someone is not giving an argument but instead just making a statement, then their character matters—especially their intellectual character. If someone simply tells you X is true, and they have a reputation for lying, then their word is not a good reason to believe that X is true. In a sense, the only evidence you have is their word; but if you have good evidence that their word is not reliable, then you have good reason to doubt them.
Likewise, if they have drawn conclusions about medical issues that you not only know are false but are outlandish, then you have good reason to not trust any other conclusion they have drawn on medical issues. If they have concluded that there is alien DNA used in medical experiments, and that cysts and endometriosis are caused by demon dream sex, then you have good reason to doubt they are right when they say they have concluded that hydroxychloroquine can cure COVID.
Or suppose someone has concluded, despite the fact that the U.S. didn’t see its first 100 deaths until March 17th (and winter ends on March 20th), that COVID is not a “killer pathogen” because there wasn’t an excess number of winter deaths in North America. (This would be like saying the U.S. casualty rate in WWII was not high because very few American soldiers died in the European theater before D-Day). This is preposterous. You’d be right to doubt them when they say they have also concluded that the (still insignificant) spike in deaths that occurs when the pandemic hits isn’t due to COVID, but simply due to people being locked inside. And if the person telling you about this argument, and how convincing it is, is also convinced by arguments which suggest that Bill Gates is a Nazi—well, then that is a huge red flag. Does it prove the argument is bad? By no means. But it gives you very good reason to suspect it is.
Now, to be clear, the intellectual character of a person giving an argument can be relevant if the only reason you have to think the premises of the argument they are giving are true is the word of that person. If you can verify them independently, then you should. But if you just have to take their word for it, their intellectual character matters—as well as their academic and intellectual reputation.
Say, for example, to prove that masks don’t work to help the spread of COVID, a friend quotes a line in a study by bin-Reza which says, “None of the studies established a conclusive relationship between mask/respirator use and protection against influenza infection.” But when you looked at the study and saw the sentence in its full context, you realized that the authors were saying masks and respirators were equally effective (not ineffective).
What’s more, you found that quote came from the part of the study about influenza and that the authors specifically state that their findings about influenza cannot be extrapolated to things like SARS (or thus COVID) because “SARS is an unusual acute viral respiratory infection with a very different epidemiology to almost all other respiratory viral infections. It is fundamentally different from human influenza.” And, the authors of the study specifically state their study did find that “mask and⁄or respirator use was independently associated with a reduced risk of severe acute respiratory syndrome.” But your friend just left all of that out.
Someone who so demonstrated such a propensity to misrepresent a study only once would rightly be subject to doubt. If someone went on to do that seven, or even 42 more times, you would be justified in never trusting them again. They would have proven that there are either unqualified to understand such studies, or not trustworthy enough to honestly report their findings. So if they went on to quote lines from 100 more studies, that all made it sound like masks don’t work, you would be justified in doubting what they said, every time. Indeed, it would be a waste of time to investigate their claims further.
So, when it comes to trusting the advice, conclusions, statements, or premises of people proclaiming to be experts about infectious diseases, intellectual character matters. It’s not fallacious to doubt what people are telling you if they have proved themselves to be unreliable.
