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Video for reasoning

The Simpsons: Season 3, episode 4

Video available at SimpsonsWorld;
Link to episode description

In this video, reputed mobster Fat Tony Williams defends his questionable actions to Bart. Bart has taken a job with Fat Tony and had been asked to store a large quantity of cigarettes at his house. Bart later finds out that a truck of cigarettes has been stolen and asks Fat Tony about it.

This clip shows two types of reasoning — deductive and analogical — and at least three logical fallacies. The students can be asked to identify these. This videoclip is currently available for free at


In-class activity for distinguishing facts and opinions

It can be a challenge for college students to distinguish facts and opinions in writing and speaking, but it is so important for public speakers to be able to do this with their own information so that they know where they will need to provide more support.

I used a sample story for students followed by a series of questions to illustrate that the lines between fact, opinions and inferences are not always clear-cut. I can’t find that exact story online and do not know if I am allowed to type it in since I got it from an educational publication, but I found a similar example online at problem 2. It has an answer key as well.

There are also several examples online of brief statements that ask students to identify facts and opinions, much like problem 1 on the above link. These could be done as a group discussion (this is how I did it) or as a small group activity with groups also discussing how they could support the opinions or inferences in a speech.

If you have found any other paragraph examples online, please let us know in a comment.

Cartoon for reasoning: fallacies

Link to cartoon

by Gary Varvel, August 25, 2011

The students tend to appreciate this example of circular reasoning.

Bad reasoning as well as …

Bad reasoning as well as good reasoning is possible; and this fact is the foundation of the practical side of logic.

Charles Sanders Peirce, identified as ‘America’s greatest logician’

What this country needs …

What this country needs is more free speech worth listening to.

Hansell B. Duckett (this one may be apocryphal as I could not find out anything associated with this name except other quotes…)

In-class activity for reasoning: fallacies

This is simple but an active way to introduce the ideas.

  • Sort the students into the same number of groups as the number of fallacies you wish to cover. (I like to have them count off to move around and work with someone new for this assignment).
  • Assign each group a fallacy from the list.
  • Have them use their books or, if you wish, the web site to define their fallacy and then to create an example.
  • Talk through the list, having students provide the definition and example (with any additions you want to make). I then follow up with my own examples and ask them to identify them.
  • Collect their fallacy examples and use the best ones on the test in a question like “identify the fallacy demonstrated in the following examples.”

This takes some time, but gets the students more involved in defining the fallacies and they like seeing their examples pop up on the test.

Update: In October 2012, I added a file with several test bank questions and original examples of fallacies here: teacherspayteachers

Video for reasoning: fallacies

Video for reasoning: fallacies

Simpsons: Season 7, episode 23

This is generally a dreadful episode, but there is a great example of a post hoc fallacy in a brief clip. After the mayor has started a “bear patrol” to keep the city safe, Homer and Lisa debate the patrol’s effectiveness. Lisa picks up a rock and argues that this rock must keep tigers away because there are not tigers visible. Rather than take the point, Homer offers to buy the rock.

Video for reasoning: fallacies

Video for reasoning: fallacies

I Love Lucy: Season 3, episode 15

Midway through this episode there is a scene where Lucy first tells Ricky about her “million dollar idea” to make and sell salad dressing. Ricky brings up some practical concerns about the plan, and Lucy rebuts him but reminding him it is a “million dollar idea.” It is a brief clip and a great example of circular reasoning (begging the question).

If you can’t write your …

If you can’t write your message in a sentence, you can’t say it in an hour.

Dianna Booher, Corporate communication expert

In-class activity for reasoning

Photo of Mindtrap game

Using selected cards from the game Mindtrap, I developed a brief exercise for students to do before discussing reasoning.

  • Break the students into small groups.
  • Each group should assign one person to be a recorder, they do not participate in the activity but observe and make notes and share their observations with the class in the debriefing.
  • Each group gets one Mindtrap card (actually I give them a copy since the cards have the answers on the back). They are to work at solving the problem.
  • If they get stuck, they can ask for a hint.
  • If they finish quickly, they can ask for another.
  • After about 10 minutes, have the recorders describe how each group solved or attempted to solve the problem.

Most of the problem solutions will use deductive reasoning, so I then start with that discussion and compare it to their problems.