People love to argue. We all have views and opinions, and we tend to promote them prominently and viciously attack opposing ideas. There is nothing inherently wrong with that as long as your views are evidence-based and you use proper logic when attacking your opponent’s position; however, many people fail at this and succumb to logical fallacies. One of the most common blunders is something known as a straw man fallacy. This occurs anytime that you misrepresent your opponent’s argument, then attack that misrepresentation instead of the view that they actually hold. It is a fairly simple concept, but it is often misunderstood, and it is rampant in debates (this year’s presidential election has been full of a sickening number of these fallacies). Therefore, I want to talk a bit about this fallacy and when it does and does not occur, as well as explaining a particular subset of straw man fallacies known as reductio ad absurdum fallacies.

Straw man fallacies

Let’s begin with the basics, what are straw man fallacies? To put it simply, they are distortions of an argument that usually present a weak and easily defeated version of the actual argument. In other words, one debater will claim that their opponent believes view X (which is a distorted and weakened version of what their opponent actually believes), then they will explain why X is wrong. The problem with this should be obvious. If the opponent does not actually believe X, then showing that X is wrong does nothing to address the opponent’s actual beliefs. In other words, it doesn’t matter if X is wrong if X isn’t actually what your opponent is claiming. Nevertheless, this fallacy can be an extremely persuasive (albeit invalid) debate tactic that many people are duped by.

On that note, it is worth mentioning that although straw man fallacies can be deliberate, and many people use them with the intention of deceiving their audience, they can also occur unintentionally. This usually happens when someone is ignorant about the topic that they are debating, and I frequently encounter these arguments when talking to people who reject scientific results. For example, one of the most common creationist arguments is, “if we evolved from monkeys, then why are there still monkeys?” This is a straw man fallacy because evolution does not state that we evolved from monkeys (or even great apes). Rather, it states that we share a common ancestor with them. Thus, by making this argument, creationists are not in any way shape or form presenting a legitimate criticism of the theory of evolution, because they are attacking a claim that evolution does not actually make. Similarly, I often encounter religious people who say that climate change can’t be true because their religion says that the earth won’t be destroyed, and climate change says that it will be destroyed. If you actually understand climate change, however, then the problem with that line of reasoning is obvious. Namely, climate change does not claim that we are going to destroy the earth. Climate change is a serious problem, but it won’t cause our extinction.

I wanted to use those two examples not to attack creationists and climate change deniers, but rather to illustrate an important point: you need to understand a given topic before you decide whether or not to accept it. Otherwise, your arguments will often be straw men fallacies, and they will make your opponents think that you are ignorant, rather than making them actually consider your position. Further, this is important for far more than just winning debates. I personally care more about knowing what is true than I care about winning a debate, but if I have not even bothered to learn the fundamental concepts of the opposing position, then I can’t have any confidence in my conclusions. You need to actually study a topic thoroughly, before you reach a conclusion, and defiantly before you try to debate someone on it.

What isn’t a straw man fallacy

When it comes to the internet articles, public debates, and other venues where someone is not specifically debating you, do not assume that someone is committing a straw man fallacy just because they did not address a specific argument that you personally think works. In other words, if they attacked an argument that essentially no one actually uses, then they committed a straw man fallacy. However, if they attacked an argument that many people use, then they did not commit a fallacy even if you do not personally use that argument.

Let me give you an example of what I mean. Last week, I wrote a post debunking 25 common arguments against climate change (mostly arguments that climate change isn’t happening or we aren’t causing it). All 25 of them are arguments that I personally encounter frequently when debating people. Nevertheless, some people were quick to accuse me of committing a straw man fallacy, and they did so based on the grounds that they personally accept that we are causing climate change, but simply debate the amount of change that will happen (which is not a line of reasoning that I addressed). So, did I commit a straw man fallacy? No! Every argument that I addressed is an argument that many people actually use. The fact that some people have arguments that I did not address does not make the arguments that I did address fallacious. I cannot predict the argument that every single reader of my blog will use.

To be clear, if I had made grand, generalizing claims like, “everyone who debates climate changes believes these arguments” or “these are the only arguments against climate change,” then I would have committed a straw man fallacy. Similarly, if I was actually directly debating one of these people, and they said, “I accept that climate change is true, but I disagree about its extent” and I responded by providing them evidence that it was true, then I would have committed a straw man fallacy, because I would not actually be addressing the argument that they had made to me. I cannot, however, be held responsible for failing to predict every single argument that anyone anywhere in the world would ever make.

A similar example frequently occurs with anti-vaccers. I often write and share posts about vaccine effectiveness, and almost every time that I do, I get some angry anti-vaccer yelling at me with statements like, “This is such nonsense. The issue is about whether or not vaccines are safe, not whether or not they work!” As with the climate change arguments, however, there certainly are people who accept that vaccines work but erroneously think that the costs outweigh the benefits; however, there are also many people who do, in fact, deny that vaccines even work. So unless I am specifically addressing a group of people who are arguing about safety (rather than effectiveness), there is nothing fallacious about discussing vaccine effectiveness, because many people do actually argue that vaccines aren’t effective.

Reductio ad absurdum fallacies

At this point, I want to shift gears slightly and talk about another type of logical fallacy that is really just a special case of the straw man fallacy: reductio ad absurdum. That may sound like a Harry Potter spell, but it is actually a logical fallacy that occurs when you take a position, stretch it to an absurd conclusion that would not actually be supported by the original statement, then claim that the original statement must be wrong because the conclusion is clearly absurd. That may have sounded complicated, so let me give you a few examples.

On several occasions I have shared posts which explain that most people don’t need to take extra vitamins and dietary supplements because they already get a sufficient amount from their diet and their body can’t really utilize excess amounts. Whenever I share these posts, however, I almost invariably get responses like, “You’re such an idiot! You claim to be a scientist and you don’t even know that vitamins are important!? You would die without them!” Let’s think about this for a second. Did I claim that vitamins aren’t important or that your body doesn’t need them? No, I didn’t even imply it. There is a huge difference between saying that you don’t need to take excess vitamins and saying that you don’t need any vitamins. In other words, the argument that I presented states that most people in industrialized countries already get the vitamins that their bodies need from their diets, and they don’t need to take extras. Internet trolls then took that argument and stretched it to the absurd conclusion that vitamins weren’t necessary at all, then accused me of being an idiot based on that clearly absurd conclusion. Do you see the problem? The conclusion that they presented was based on a distortion of my argument, rather than the argument itself.

To give one more example, on several occasions I have shared posts that explain why juice cleanses and “super foods” can’t actually boost an already healthy immune system, and the wonderful people of the internet usually respond by asserting that it is obvious that a healthy diet is important and your immune system won’t function well if you’re malnourished. As with the vitamin argument, however, I never asserted that a healthy diet isn’t necessary. I was talking about boosting an immune system above its normal functioning levels, not basic nutrition. In other words, saying that you can’t boost a healthy immune system is not the same thing as saying that you can eat nothing but junk and expect to be healthy.

Reductio ad absurdum logic

This illustrates the correct use of reductio ad absurdum logic. The second stick figure is sarcastically illustrating that if the argument that science has been wrong in the past actually invalidated a current scientific result, then we could use that argument anytime that we wanted, but that would obviously lead to absurd conclusions. Note: sarcasm is not a requirement for reductio ad absurdum logic, but it is often included.

Finally, it is important to note that reductio ad absurdum logic can actually be applied without committing a fallacy if you can show that the actual argument that your opponent is using would lead to an absurd conclusion if it was applied consistently. As long as you do not distort the original argument, then this technique is not only valid, but it is extremely powerful (it is one of my favourite tools).

Let me give you an example. I often encounter people who say things like, “all that I need to know about climate change is that Al Gore thinks it is happening. If he thinks that it is true, then it must be wrong!” This argument is technically a guilt by association fallacy, but we can easily demonstrate the flaw in it by using reductio ad absurdum logic. In this case, I usually counter this claim by pointing out that Al Gore also thinks that we are breathing oxygen, so if we use this argument consistently, then we must conclude that we are not in fact breathing oxygen. Do you see why that response works? I did not distort the argument, rather I showed that it actually would lead to an absurd conclusion if it was a good argument. I can prove this by setting up two identical syllogisms.

Original argument:

1. If Al Gore thinks that something is true, then it must be wrong
2. Al Gore thinks that climate change is true
3. Therefore, climate change is wrong

Analogous argument using reductio ad absurdum logic:

1. If Al Gore thinks that something is true, then it must be wrong
2. Al Gore thinks that we are breathing oxygen
3. Therefore, we aren’t breathing oxygen

See how this works? I simply took the original argument, applied it to a different topic, and showed that if we apply that argument consistently, we arrive at an absurd conclusion. I provided many more examples of this debate tactic in this post on consistent reasoning, so please see it if you are confused. You should also watch John Oliver, because he wields this logical tool brilliantly (sometimes he does also slip into reductio ad absurdum fallacies, but that is generally to set up a joke rather than make a serious argument).

Conclusion

In short, straw man fallacies are simply distortions and misrepresentations of your opponent’s argument. They can be intentional or unintentional, but they are easy to avoid by simply being well-informed on the topic that you are debating. Nevertheless, many people continue to use them and incorrectly accuse other people of using them. Additionally, these fallacies contain a special subset of fallacies known as reductio ad absurdum fallacies. These occur when an argument is stretched to an absurd conclusion that is not supported by the original argument. Although that strategy is fallacious when the argument is distorted in the process, it can also be a very powerful debate tool if you can demonstrate that the original argument itself actually leads to an absurd conclusion when it is applied consistently.

Note: I want to be clear that on topics like vaccines, climate change, evolution, etc. there really aren’t “two sides.” So I when I say that you need to thoroughly study the topic before reaching a conclusion, I am not suggesting that you need to read a bunch of conspiracy blogs, creationist websites, etc. Rather, you need to study the peer-reviewed literature (including the handful of studies that disagree with the consensus). You don’t need to read unreliable sources in order to be well-informed. However, if you want to actually debate people about these topics, then you really should spend time studying those unreliable sources, because if you don’t, you will often end up committing straw man fallacies. Indeed, I have seen my fellow skeptics do that on several occasions (and I’ve probably unknowingly done it myself at some point).  

Related posts

• Stop accusing me of ad hominem fallacies you stupid idiots
• The genetic fallacy: When is it okay to criticize a source?
• The nirvana fallacy: An imperfect solution is often better than no solution
• The Rules of Logic Part 3: Logical Fallacies
• The Rules of Logic Part 7: Using Consistent Reasoning to Compare Apples and Oranges