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Logical fallacies – debunking pseudoscience

Last updated on January 28th, 2016 at 01:07 pm

Logical fallacies are essentially errors of reasoning in making an argument – identifying them is an excellent tool in debunking pseudoscience and other junk science. When logically fallacious arguments are used, usually based on bad reasoning to support a position (or to try to convince someone to adopt the same position), it is considered a fallacy.

Most of you didn’t know, because I didn’t promote it much, but I had a link in the menu for a list of logical fallacies. It lay fallow, barely read by me or, apparently, anyone else.

However, I decided to update and improve my list of favorite logical fallacies used by all of the pseudoscience crowd. There are many more logical fallacies than what I list, but this blog is focused on providing evidence, in a snarky way, against anti-science claims made by everyone from the vaccine deniers to creationists.

Most pseudoscience arguments, because they totally lack evidence, require a whole list of logical fallacies to make their point. In fact, a whole meme industry has arisen from the creation of “logical fallacy bingo cards.”

I’ve been on the pro-science side of every issue I can imagine since I graduated from college. You name it, I fought for it.

Evolution–it’s a fact.

GMOs–safe and will help feed the world.

AIDS–caused by HIV.

Climate change–well at first I wasn’t quite sure, so I had long conversations with some of the leading researchers in climate change, who pointed out some of the best published studies to read, and I was solidly on board. The evidence is both compelling and convincing.

And finally vaccines–the benefits of preventing communicable disease by vaccines is overwhelmingly supported by evidence from real science. It isn’t even close.

The vaccine denier cult loves nearly every single logical fallacy (BINGO!!!!!).

  • The Big Pharma Shill Gambit – I and every other pro-science writer involved in vaccines is, according to the deniers, is a paid employee of Big Pharma, who only writes because the pharmaceutical overlords require us to write positive things. We cannot be trusted because we are so biased by those gold bars shipped to our homes every day.
  • Confirmation bias and cherry picking – always searching for research and articles that support their a priori conclusions, rather than examining all the research to reach a proper conclusion supported by the quality and quantity of research.
  • Argument from ignorance – claiming that vaccines aren’t safe and/or effective because it hasn’t been tested in a very specific and unethical clinical trial. The antivaccine crowd would  probably state that if the vaccine isn’t tested when there is a full moon with an ambient temperature at 22.8ºC at sea level, how can you be sure it’s not safe? That’s why it’s called the argument from ignorance, and not the argument from brilliance.

But the worst, and most vile, logical fallacies used by the vaccine deniers is the argumentum ad hominem, or the ad hominem argument. Essentially, this fallacy centers on attacking a person, instead of attacking the argument or evidence. The goal is to discredit the person, which would hopefully discredit the argument.

For example, Dorit Rubinstein Reiss, who writes frequently on this blog about vaccines and the law, is attacked regularly by the haters. Generally, Professor Reiss is one of the most civil and logical people involved in the false debate about vaccines (it’s not a debate, when one side, pro-vaccines, has around 99.999999% of the supporting evidence). But she’s always attacked in the most nasty and hateful ways imaginable.


Note: original tweet can be found here.

This clueless, ignorant fool calls Reiss a “shameless self-promoting corporate fascist hack.” Since Professor Reiss is a faculty member at a fairly high ranked Law School, and by law or tradition, publicly reveals any potential conflict of interest, and there is none, then these ad hominem attacks fall flat and are ridiculous. He could not spend a nanosecond trying to present real evidence, but just personal attacks.

The irony of this particular instance of an ad hominem attack is that it was in response to Reiss’ article about Dr. Paul Offit – she wrote about various vicious and disgusting personal attacks on Dr. Offit by a fellow pediatrician, Bob Sears. Her point was that if all you can do is use personal attacks, then you’ve got nothing.

And that’s what I think of the personal attacks on Professor Reiss, Dr. Offit, Allison Hagood, and many other people who do yeoman’s work in the standing up to the lies and ignorance of the antivaccination cult – the attackers have nothing, no evidence, so all they have are personal attacks.

Just to be clear, I love personal attacks and ad hominem arguments. But only if they aren’t logical fallacies.

I have a rule. If I’ve discredited  your “beliefs” with nearly irrefutable evidence that has been published in high quality journals and represents the scientific consensus. And if your “beliefs” are based on your 30 minutes of researching immunology on Google, compared to someone’s spending a whole life investigating one small part of immunology.

Then at that point, I’m going to be merciless in my personal attacks and ad hominem arguments. It’s because I’ve got the evidence, and if you  want to be ignorant about that evidence, I have no further interest in civility. In other words, in my world, you get 1-2 chances to be logical. After that, I’m done.

Anyways, I hope that you find my list of logical fallacies an interesting read. I haven’t included them all, as I mentioned, because some are rather obscure. I will add more over time. If you think I need to add some key ones, point it out to me on Twitter, Facebook, or in the Disqus comments.


Michael Simpson

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