The ability to pick out a ‘flaw’ or ‘mistake’ in an argument is a useful one. You can really test out your thinking skills when you try to pick out a flaw in an argument because it requires you to:
- Think about what is being said in the argument.
- Break down the argument into parts
- Find out where linkages in those parts can be disputed.
It’s also very useful to know for real life.
For example, you might be at a shop and a shop keeper insists that the oil that they’re selling for $80 is excellent in deterring flies from entering your property because it acts as a physical barrier. But… you know how to think through arguments and pinpoint flaws.
You know that flies have wings and can fly over oil so that oil is going to be useless as a physical barrier. Also, if sprayed, oil doesn’t stay in the air because it’s heavier. Good thing you didn’t buy that oil – you just saved yourself $80!
There are many ways and different types of flaws in arguments and we’re going to look at the different types to help you become more familiar with flaws – so that you can start to think more strategically about arguments and be able to pick up flaws.
What’s a flaw in an argument
As we saw above, a flaw is a ‘mistake’ or a ‘hiccup in reasoning’. And also, as we saw in previous checkpoints, thinking is very much context based so there’s no one rule that can be applied in all areas and you’ll have to unpick things based on your comprehension. But… there are general rules that can be used and knowing these, along with practicing your thinking skills, will make it easier for future questions you might encounter from familiarity.
How to pick out flaws in an argument
Here’s how you can pick out flaws in an argument.
- Read the argument and break it down into parts e.g., claim, evidence and linkages.
- Recall memory for common flaws to see if any are present in parts or linkages.
- Identify the flaw.
Remember, picking up flaws is very much applied so practice and time helps you develop your ability to do so.
Common Flaws & Examples
Below are some examples of common flaws often seen in arguments. It’s unlikely that you’ll need to recall the names of the flaws and instead, it’s more likely that you’ll have to identify the flaw in an argument.
Watch the video for a full explanation on the common flaws and how to pick out the flaw in each of the examples provided.
- Causation/correlation error – this is when two sets of information are linked together incorrectly. For example, last year, all the students in Mrs H’s class achieved A+ scores while those in Mrs T’s class all achieved C scores. Let’s try and get into Mrs H’s class so that we can get the best education possible. Where’s the flaw in this argument?
- Assumptions without basis – this is when an assumption is made without having considered other possibilities. It’s very common. For example, Mila is not at school again, she must be hanging out with her cousin! Where’s the flaw in this argument?
- What’s your proof? – this is when a ‘generalisation’ is made based on limited evidence. You can see this on the label of skincare products that make a ‘claim’ about skin improvement based on a study of 15 people! An example is: Everyone who has been nice to me is named “Jessie”, therefore, every “Jessie” is a nice person (Psst… I’ve only met 2 “Jessies”). Where’s the flaw in this argument?
- Comparing apples with kangaroos (comparison fault) – this is when a comparison is made with two items that shouldn’t really be compared or differ with a subtle difference. For example, John and his brother Frank, go to the same school. John gets an F while Frank gets an A. John and Frank’s father is upset with John’s F score and punishes both John and Frank by taking away their television rights. Frank is upset and his father argues: “You’ve received your school reports and when you both participate in something together like school, you are a team and therefore, as a team, if one person is punished, then both are punished”. Where’s the flaw in this argument?
- Quantity and percentages – when references are made to percentages, the absolute underlying number could be insignificant and can reduce the power of their argument: 50% of 10 is 5 people, while 50% of 1 million people is 500,000 people. You see this often in marketing material to create a ‘bigger’ impression. For example, 80% of people surveyed in the local area expressed grave concerns about the planned construction of a hotel. (Psst… I only surveyed 10 people). Where’s the flaw in this argument?
- Lack of evidence as proof – this is when it is assumed that someone didn’t do something because there is no proof of it. A famous example was the 2020 COVID-19 virus tweet that said “there is no evidence of human-to-human COVID-transmission” and mistakenly, it was believed that the COVID-19 virus couldn’t be passed from human to human. Here’s another example: Ellie claimed that Pearl spread rumours about Nikki on social media. Mr Constable could not find evidence that Pearl (e.g., Pearl didn’t have the post up and she didn’t have a profile) spread rumours about Nikki and so he concluded that Ellie was lying. Where’s the flaw in this argument?
- Not 2 options only – this is when an argument assumes that someone is on one side or the other and that other possibilities don’t exist. For example, Nikki isn’t friends with us because she chose to play with Pearl at lunch time. Where’s the flaw in this argument?
- Possible vs certain – this is when something is claimed as being certain or possible incorrectly. For example, it is certain that global warming will lead to the end of humanity unless we act now. Where’s the flaw in this argument?
- Circular reasoning – this is when you claim something and then rely on that claim. Mrs H is the school’s most liked teacher. Why? Because she is popular. Where’s the flaw in this argument?
- “Do as I say, not as I do” – this is when a criticism is made in reference to another’s behaviour to undermine the argument. My friend Jenny doesn’t do homework and she gets A+ in her exams so I don’t need to do homework too. Where’s the flaw in this argument?
As you can see from above, there are a lot of ways in which arguments can be ‘flawed’ and being able to pick these up can better help with gaining greater clarity (and assist in your exam!).
Key Rules to remember
- Picking out flaws requires breaking up the argument into parts and looking closely at parts that could be ‘defective’ including the links that join these parts.
- Be aware of the common flaws and run through each mentally to see if the argument presented to you may contain any one of them.
- Remember, picking out flaws is unique to each argument – so it’s important to take time to think through arguments in practice and consider how they could be flawed.
Practice time!
Now, it's your turn to practice.
Here’s a thought experiment #6.
Remember, there is no formal answer and this experiment is provided to help stimulate your creativity and critical thinking (a ‘thought experiment’ is provided at the end of every checkpoint except checkpoint 18).
Thought experiment 6:
How can you prove that your memory works?
Take your time to work through this thought experiment as it is not assessed and provided to help develop your deeper thinking skills. Think about various components of the question. What questions will you ask yourself and how do you answer your questions?
Now, let’s turn to the checkpoint questions.
Click on the button below and start your practice questions. We recommend doing untimed mode first, and then, when you're ready, do timed mode.
Every question has two solutions videos after you complete the question. The first is a quick 60 second video that shows you how our expert answers the question quickly. The second video is a more in-depth 5-steps or less explainer video that shows you the steps to take to answer the question. It's really important that you review the second video because that's where you'll learn additional tips and tricks.
Once you're done with the practice questions, move on to the next checkpoint.
Now, let’s get started on your practice questions.
