Antivaxxers use well-understood logical misdirections called "fallacies" to make their claims appear supported by evidence.
In this article, we'll show you some of the most common with actual examples.
Confirmation Bias and Cherry-Picking
Confirmation bias takes place when the antivaxxer shows, not a body of evidence that represents the population, but only the examples which fit the theory. The process of picking out only the "good" examples is called cherry-picking.
With enough random data, you can use this technique to seemingly prove anything.
There must be a conspiracy between sellers of sandwiches and sellers of vaccines. In fact, look at this! How do you explain that this Subway sandwich restaurant just happens to be set up next to this hospital?
Of course, zooming out from this map, we would see the number of Subways not placed next to hospitals is vastly more representative of the population.
This is a silly example of course, now look what happens when someone uses scare tactics to push their agenda against vaccination:
It's worth remembering that in developed nations, vaccines are very common, and hopefully they will continue to be. As such, it's very easy to go back over data for victims of infant mortality and children who tragically succumb to disease and find the ones who had previously taken a vaccine.
That brings us to the next fallacy...
Post hoc [ergo propter hoc]
Often just referred to as the "Post Hoc" fallacy, the phrase is Latin for "after this, therefore because of this."
If you interview anyone who has received a vaccine in their life, you'll be amazed how many of them did purchase and consume a sandwich afterwards. But the fact that much of the population afterwards did something most people do at some point in no way proves one caused the other.
The Tamiflu argument is infamous for the Post Hoc fallacy. Tamiflu is a medication that does not cure the flu nor prevent it, but it can inhibit the virus's effect on the body.
If we align the story to say "Person took Tamiflu, then the person died" we are saying the latter happened because of the former.
Remember that Tamiflu is taken by victims of the flu. Healthy people do not take it because why would they? So by looking at the outcomes of those who take Tamiflu, we are taking a sample of the population who has a potentially deadly illness—the flu. Of course there will unfortunately be deaths.
We could make similar claims about really any cancer treatment that does not cure cancer (none do), because invariably there are people who die from cancer and many of them receive some kind of treatment along the way.
Appeal to Ignorance
The appeal to ignorance argument happens when someone posits that the absence of an explanation counter to one's claim must mean the claim itself is true.
For example, if we both found a locked box and I tell you there is a magical fairy inside, you'd probably disagree with me. But can you prove what is in the box? We shouldn't agree the box does contain a fairy because you don't have evidence to the contrary. Rather, both of our claims should be supported by evidence to be taken seriously.
Overwhelming with Technical Jargon
Also known as argument by gibberish, if the audience is unfamiliar and uncomfortable with technical and scientific language, they may find themselves unable to argue someone's position, however wrong it may be.
In the above real world example, much is incorrect and ultimately does not establish a link to vaccines themselves, which contain very little aluminum if any and in a safe form.
As for aluminum, the CDC clarifies in this article how aluminum salts are used as an adjuvant in vaccines to improve their immune response. It's true that injecting a large enough quantity of aluminum in the body is toxic, as is injecting the right amount of anything in the body. However, there is more aluminum in fresh air than there is in a vaccine.
These kinds of arguments came up so often, the satirical website DHMO came into existence to warn the public of its dangers. It is absolutely true that Dihydrogen Monoxide includes dangers such as
- Death due to accidental inhalation of DHMO, even in small quantities.
- DHMO is a major component of acid rain.
- Found in biopsies of pre-cancerous tumors and lesions.
...and many others. It is also true that Dihydrogen Monoxide is a chemical name for water. Take caution with chemical arguments. They take advantage of the fact we aren't all chemists.