When people are wrong about something, it’s often because of a logical fallacy.
Logical (or rhetorical) fallacies are errors in reasoning. They occur frequently in politics and the media, and often go unnoticed. At first, they usually seem to make sense. It just sounds right.
But when you stop and think about it critically, it becomes apparent that the assertion is faulty.
There are many types of logical fallacies, and philosophers have been talking about them for ages.
It’s useful to understand the most common types – so you can prevent yourself from making them. And more importantly, so you aren’t fooled by someone else.
Learning this information might save you a lot of money, or at least save you some embarrassment. It might even save your life.
Introduction – and some resources:
I’ve been wanting to talk about logical fallacies for a while now. They are just so important when interpreting the research / science that’s discussed on this site.
What’s kept me from writing about it more was… well… I couldn’t think of a way to make it not boring.
Luckily, I found this website… which is absolutely amazing.
I highly recommend this site. It’s super simple, and beautifully designed. Very useful information to be aware of – when reading the news, learning something, and especially when you’re in an argument! Study them all! Big shout out to the creators: Jesse Richardson, Andy Smith, and Som Meaden. Great work!
Here’s another great site with even more examples:
It also includes a great example of how to tear an argument apart using your awareness of logical fallacies – in this case Cardinal O’Briens argument against same-sex marriage.
Some of my favorite logical fallacies…
- ‘False Cause’
I’ve written about this briefly before in ‘Correlation does not mean causation’. It’s assuming that because two things tend to occur at the same time (or one right after the other), that one is the cause of the other.
For example: – The more firefighters there are at a fire, the bigger the fire tends to be. (that’s a correlation) – Therefore, firefighters must cause bigger fires. (that’s an attempt at establishing causation – and in this case, it’s quite false!)
Examples like this are really obvious – they make good teaching tools. But every day logical fallacies happen that are not so obvious.
Let’s move on to some more fun ones:
- ‘Appeal to Nature’
This one is happens all the time in the world of health and fitness, especially nutrition. The intentions are good, and sometimes it’s true. However, just because something is ‘natural’ doesn’t mean it’s good for you!
There isn’t anything much more ‘natural’ than the sun – but frequent sunburns can increase skin cancer risk.
Dying because of the common flu, or an infection from a small wound is completely ‘natural’. Modern medicine is often criticized for being ‘unnatural’, yet it’s the reason many of us survived childhood. I had pneumonia as a child, which was the number one cause of death in the year 1900. Good thing I was born in the 80’s – or I might not be writing this!
Getting eaten by a lion is also ‘natural’.
Nature is cruel and unforgiving, and it doesn’t care what you believe in.
- ‘Ad hominem’
This one particularly annoys me. It’s when people attack their opponents personal traits instead of engaging with their argument.
For example – let’s say I decide (and I often do this) to criticize an unsubstantiated claim for its lack of scientific merit. Instead of rebutting my points, someone might come back complaining about the ‘tone’ of my writing, or my ‘motives’… or they take it personally and just get angry.
Complaining about how someone said something instead of what they said is totally ignoring the potentially valid point they are making (even though being upset when someone is rude is totally understandable).
You make them out to be the ‘bad guy’, when in fact, they may be right!
- ‘Appeal to authority’
Basically, this is name dropping. You use a famous / special / important person or institution to back up your claim, instead of actually providing real evidence.
For example: “This product is supported by the national association of snake oil salesmen”. That’s not really proof of anything, no matter how credible the association.
Furthermore, you assume that just because a person is regarded as some sort of guru, they must be right – I like to call this “guru-ism”, and it’s a huge problem in healthcare and fitness.
I hope I never become a “guru” – just someone who writes well about good science.
This is potentially the most dangerous logical fallacy in health care. As the website I posted above states: “Using personal experience or an isolated example instead of a valid argument, especially to dismiss statistics.”
This is the basis of most science denialism.
For example: a new research study proves that some nutritional supplement actually doesn’t help whatever it’s supposed to. Someone might say “well I know it works, because it worked for me”. But there are many reasons why it might have seemed to “work” for them – see ‘Why Science – Part 1 – Because we’re usually wrong’.
One persons example doesn’t give us much info (and they could be straight up lying!) - that’s why we do careful research studies and statistics to find out whether something works or not in healthcare and fitness.
Some basic knowledge in logic and reason is important when thinking critically. It’s something we should all be aware of, and it should be taught in high schools. Critical thinking is important for anything from reading the news, to making important decisions about your health.
It’s clear that a knowledge of logic is important when interpreting scientific research. Since I write about health, fitness, and therapy research on this website, being aware of logical fallacies is important to me. I’ll admit – I’ve probably committed a few logical fallacies myself. If you ever notice any – do not hesitate call me out with a comment or e-mail! I’d seriously appreciate it!
Hope you learned something!