Think Again IV: How to Avoid Fallacies

CONTENT: In this week's material we will describes two phenomena that are both common and useful in the languages that human beings speak, but both of which give rise to the potential for fallacious reasoning. A word or phrase is vague when its meaning is not precise, and it is ambiguous when it has more than one meaning. When we use vague or ambiguous phrases in our reasoning, it is very easy for us to make a number of different kinds of fallacies. This week will teach you what these different kinds of fallacies are, and give us some practice in spotting them, so you can make sure to avoid them in the future. LEARNING OUTCOMES : By the end of this week's material you will be able to: define what a fallacy is distinguish various kinds of fallacies understand the linguistic phenomena that give rise to fallacies identify various kinds of slippery slop fallacies where they occur identify various kinds of fallacies of equivocation where they occur OPTIONAL READING: If you want more examples or more detailed discussions of the fallacies that result from vaguness or ambiguity, we recommend Understanding Arguments, Ninth Edition, Chapters 13-14.

CONTENT: Now we will describe another common set of fallacies: fallacies that occur when an argument makes no progress from its premises to its conclusion. Sometimes, arguments make no progress because the conclusion is already contained in the premises. Sometimes, arguments make no progress because the conclusion is presupposed by the premises. And sometimes, arguments make no progress because the premises don’t make any claim at all, even if they might sound like they do. When you know how to identify such fallacies, you will find that they are more common than you think! LEARNING OUTCOMES: By the end of this section you will be able to: identify various kinds of circularity or vacuity where they occur OPTIONAL READING: If you want more examples or more detailed discussions of these topics, we recommend Understanding Arguments,Ninth Edition, Chapter 16.

CONTENT: This week we will teach you various strategies for refuting a fallacious argument. To refute an argument is to show that the argument is unsuccessful. Even if you are able to identify a fallacious argument as a fallacy, you might still not be able to prove to others that it is a fallacy. In this week, you will learn a variety of techniques for proving to others that the argument is a fallacy. LEARNING OUTCOMES: By the end of this week you will be able to: refute fallacious arguments OPTIONAL READING: If you want more examples or more detailed discussions of these topics, we recommend Understanding Arguments, Ninth Edition, Chapter 17.