Class 10 - Some Common Fallacies

Welcome back

Today we’re going to be talking about how arguments go wrong. We’re going to be looking at bad arguments, and we’re going to be coming up with some bad arguments of our own. But first, let’s check in.

Discussion

• What did you find interesting about the reading?
• What questions did it leave you with?

Arguments

One way of thinking about arguments, as we have already said, is by thinking of them little machines. When we use machines like computers or hammers or cooking stoves or knives, we don’t tend to think too hard about how they work unless they break down. But once they start to break down, then we have to think harder about how they work and what has gone wrong.

Arguments are exactly the same. When arguments work — when we managed to persuade other people with our arguments — then we don’t need to think too hard about them. We use unlike any other tool or machine, more or less unthinkingly.

But we all know the experience where an argument doesn’t persuade us, where somebody is trying to persuade us of something and we’re not convinced.

This can also happen with our own arguments. We can find ourselves making an argument, and in the middle we have a terrible sense that this argument is beginning to break down, that the machine isn’t working. And the experience of this is a bit like driving a car or riding a bike when you realise that the car or the bike is somehow broken. You may hope that you get away with it, you may hope that the machine will take you to your destination, but you feel very uneasy and uncertain, because you know things could go very very wrong.

In the sessions last week, we looked at deductive, inductive and abductive arguments. And we talked about how these can go wrong. But the fallacies we are looking at today are not just about the logical form of arguments, but about their content and the context.

Writing Exercise:

To get started looking at some of these informal fallacies what I’m going to get you to do is think about your own experience.

Consider the following question, and write in response to it for 5 minutes:

When making arguments does it matter for an argument who speaks, to whom, from which perspective, and with what purpose?

You can write this however you like. Feel free to explore times in your own life where these questions - who speaks, to whom, from which perspective, and with what purpose - mattered for the arguments being made.

Exploring fallacies

For the rest of the session, we’re going to explore four different informal fallacies. I’ll put them in the chat.

1. Argument directed to the person (Argumentum ad hominem)
2. The Straw Man fallacy
3. Begging the question (Petitio principii)
4. Appeal to popular opinion (Argumentum ad populum)

I’ll assign one breakout group to one fallacies. This doesn’t cover all the fallacies in the text — it may have missed out your favourites — but it is a good cross-section. In your groups, I want you together to do the following:

• How would you define this fallacy in one or two sentences?
• Explore: i) why this fallacy is a problem, and ii) whether there are any occasions on which it is legitimate.
• Come up with at least two examples of this fallacy.
• Appoint a spokesperson to feed back on this fallacy, to introduce it to the rest of the group.

Discussion

First, each group will introduce the fallacy they worked on, and explain it to their fellow students.

Next, we will go through the examples that this group has provided.

THhen we will talk about where we most often come across this fallacy, why this fallacy is a problem, and whether it can ever be used legitimately.

Homework

For your homework, find one example from real life — for example, from the media — of one of the fallacies explored in this reading, and post it on the discussion board. We’ll talk through these next week.

Next week we’ll start by talking about the appeal to popular opinion (Argumentum ad populum) and straw man fallacy.