Faulty Logic: Circular Reasoning

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SWBAT write examples of opinions with errors in reasoning about a given topic.

Big Idea

Sections What is Self-Contradiction Duration: 20 minutes. In order to teach the Common Core writing standards of using reasoning to support opinions, I guide students to explore faulty logic. Faulty logic is an argument that l

What is Circular Reasoning ?

20 minutes

In order to teach the Common Core writing standards of using reasoning to support opinions, I guide students to explore faulty logic examples in this unit.  Faulty logic is an argument that lacks validity. It is sometimes referred to as paradoxical reasoning because it is illogical, absurd, or contradictory.  Not only will they need to recognize faulty logic so as to avoid using it in their own opinion writing, later they will also be expected to assess reasoning provided by the author and determine if the evidence is based on fallacious reasoning as they enter middle school and high school in preparation for research in their careers or college. Students need to build on prior knowledge to get to that point.  Starting to introduce errors in logic in the primary grades gives students the foundational knowledge needed for this critical reasoning later on.

Although the concept of faulty logic and errors in reasoning is not often taught until later grades, I decided to present my gifted, high achieving class with this challenge.  It is an experiment of sorts for my class consisting of students who are out-of-the-box thinkers. The tricky part is teaching students through non-examples. This non-traditional route of teaching shows students what not to do instead of what to do.  Students use critical thinking skills as they analyze the irrationality of their writing. This activity is a demonstration of the old adage "Learn from your mistakes." Indeed, mistakes provide opportunities for learning.

I begin this lesson by explaining the concept of Faulty Logic.  Students are introduced to the six types of Faulty Logic in this unit of study.  However, our focus for this lesson is "Circular Reasoning".  We define, explain, exemplify, and discuss its meaning and applications.  I show two movie clips: Circular Reasoning video example and Circular Reasoning example 2 video that explain the concept of Circular Reasoning.  Prior to showing the clips, I ask students to pay particular attention to the dialogue between the characters so that they can summarize afterwards and react to its content.  I show the clips one after the other, but I preface it by asking students to compare/contrast the two clips. 

Student responses were that the clips were similar because they both show illogical reasoning.  The only difference was the setting of the videos.  We discuss our reactions to the video and students share their analysis about the characteristics of circular reasoning and elaborate on why they think it is faulty logic.  I actively listen to assess student understanding and give specific feedback as needed. With the shift towards incorporating more informational texts, Common Core standards challenge students to identify irrelevant evidence and false statements.  Analyzing errors in reasoning is a powerful way to deepen students' knowledge in analyzing the accuracy of information.  Students become more critical thinkers.

This lesson focuses on the writing standard of writing opinion pieces supplying reasons that support the opinion.  Only in this case, the supports are non-examples because they are faulty logic or illogical.

Create Examples

20 minutes

We have a short discussion of prior experiences with circular reasoning that students may have in conversations, arguments, television commercials, magazine advertisements, movies, etc. We also review the movie of the two examples of circular reasoning presented.  I ask students to create their own version of Circular Reasoning or Begging the Question.  We brainstorm ideas and chart them on the board to start this process.  Students work in pairs to generate these ideas, and I facilitate as needed.  This is the gradual release for students to take ownership of this lesson.

I introduced a Persuasive Reasoning Graphic Organizer to plot out student ideas.  If the reasoning makes sense, then we should be able to complete the organizer because the argument is supported by evidence. However, in the absence of evidence, such as restating of the claim, the organizer will show that the rationale is faulty and circular since it is just restating the original claim. One example that a student shared of circular reasoning is: "Obama was the best candidate for president because he was better than the rest."  Another student said, "It's time to do your homework because it's homework time."  Students see from the graphic organizer that the reasons only restate the claim and that no supports are given. 

Sharing our Ideas

20 minutes

Students gather to present their examples of Circular Reasoning.  The feedback students give me serves as a formative assessment to determine their understanding of this lesson.  Common Core ties learning to real world experiences.  Circular Reasonin student sample and circular reasoning video presentation show that students often use examples of conversations we had in class or at their homes.  As an example of circular reasoning, one student drew a picture with a subtitle:  I love the movie because it is awesome.  Students draw from their life experiences as well as what they learned during this lesson to create their presentations.  It is also a great way to brainstorm ideas and learn from each other.