Building on what we have learnt about assumptions and principles, let’s now put that into practice and extend our thinking skills by analysing arguments and deciding what will weaken or strength an argument.

What weakens and what strengthens?

An argument makes a claim – let’s take a simple on, that smoking is bad for human health.

When you construct an argument, you add evidence or supporting sentences that help prove or enhance your point. This is what strengthens an argument. For example, “the arteries of smokers, compared with non-smokers, are often clogged with plaque and blood clots making blood flow difficult” is an example of a statement, that combined with the above, would STRENGTHEN the argument.

Why? Because it’s saying that smokers suffer from clogged arteries => bad health.

Likewise, you may have also read pieces (or written pieces yourself – I know I have!) that with hindsight, seemed contradictory – or you wonder, why did I include that? A statement that weakens an argument is a statement that proves that the claim is not true. For example, “in a fitness test both smokers and non-smokers performed at similar levels”. This statement would WEAKEN the argument.

Why? Because it says that there’s no difference in health between smokers and non-smokers so smoking isn’t bad for human health.

Easy right?

Strengthen is when a statement proves or adds to the claim being true.

Weaken is when a statement proves that the claim is not true.

Now, because deciding whether a statement strengthens or weakens an argument really depends on context and therefore, the application of our thinking skills, let’s do these example questions.

Example Question/s

Watch video for explanation of the following question/s:

Kraits (a type of snake) are usually active at night and their bites can prove fatal within as little as 24 hours. Although less than 20 per cent of the snake species found in Nepal are highly venomous, people in Nepal tend to be afraid of all snakes – according to a study of 200 people. Quite often, rat snakes — which are non-venomous — are mistaken for venomous cobras, as are wolf snakes for kraits. People’s fear of snakes is unfounded as a result of misidentification of species. (Reused and a derivative work from original source, 2020)

Which one of the following, if true, most weakens the above argument?

A. Misidentification of snake species is a common occurrence due to shared common physical appearance of some snakes.
B. In a study of 200 people who expressed fear of snakes, none had been bitten previously.
C. In the study of 200 people who expressed fear of snakes, all had correctly identified snake species.
D. Rat snakes are the most common snake in Nepal and commonly attack people.

St. Teresa’s College of Education, one of five female-only colleges in Ghana, is delivering e-learning by consolidating the use of messaging applications like Telegram and WhatsApp. The college does not have an in-built e-learning platform like Sakai, Canvas or Blackboard, and there are no officially recognized learning platforms in Ghana. At other colleges, tutors often use whichever platform they feel works best and as a result, many students download multiple applications like Google Classroom, Zoom, Telegram, and WhatsApp, some of which consume a lot of data. Making sure that all college tutors use only Telegram and WhatsApp will help to streamline learning delivery for recipients.
(Reused and a derivative work from original source, 2020)

Which one of the following, if true, most strengthens the above argument?

A. Using Zoom and Google Classroom together would produce the same result as using Whatsapp and Telegram.
B. Tutors were able to deliver twice as many lessons with just Telegram and Whatsapp.
C. Students reported greater satisfaction with the use of multiple applications and were able to use apps for multiple purposes outside of learning.
D. A decrease in non-attendance of students and engagement was reported with the use of only Whatsapp and Telegram.

Key Rules to remember

• An argument has a claim – identify what this is first and then work systematically by considering each of the options checking whether they strengthen or weaken.
• Strengthen is when a statement proves or adds to the claim being true.
• Weaken is when a statement proves that the claim is not true.

Practice time!

Now, it's your turn to practice.

Here’s a thought experiment #4.

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 4:

In order for a bug to travel from one side of a room to the other, it first needs to go halfway across the room, right? Then, similarly, it needs to go 3/4 of the way (half of the second half of the trip) before reaching the other side, right? And then it needs to go halfway through the last quarter of the trip (7/8 of the way) before reaching the other side, right? You can keep doing this forever, always dividing the last section in half. Doesn't that mean there's *always one more thing the bug has to do before reaching the other side? And doesn't that mean the bug can never reach the other side?*

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.

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