Faulty Logic: False Causality

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

Big Idea

Students use critical thinking skills to detect faulty logic in arguments. Non-examples help students learn, too! They are able to detect faulty logic in arguments and avoid using faulty logic in their own opinion writing.

What is False Causality?

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.

Using my False Causality Flip chart, I introduce this lesson by a review of faulty logic. A review is necessary to recall information learned in order to scaffold onto a deeper related topic.  To teach to the Common Core, I have made sure my instruction centers on scaffolding from basic knowledge to more complex and deeper concepts.  Then, we identify the example of faulty logic that we will focus on today: False Causality.  I do not feel it necessary to dumb down the terminology, but rather introduce it and discuss its relevance to my students.  Students should be challenged with advanced vocabulary.  A discussion of definitions and examples of false cause ensues.  We brainstorm ideas after viewing examples on the slides of my flip chart.  Brainstorming and collaborating are essential for teaching to Common Core due to the rigor involved.

I begin with assessing student's prior knowledge.  My students are familiar with cause and effect.  We begin a discussion of stories we have read in the past that has examples of cause and effect.  Students brainstorm as I plot their examples on a cause and effect graphic organizer. After plotting examples of cause and effect that makes sense, I plot non-examples listed on the flip chart on the graphic organizer so that students can see that the results are illogical and does not support an argument or claim.  By presenting this lesson in this way, I am scaffolding from concepts students already mastered to more challenging ones.

Student Creation Samples

20 minutes

After modeling a few samples of false causality using the cause and effect graphic organizer, I separate students to work in pairs and distribute the graphic organizer.  After planning out what each pair will present, students went to work on their examples of False Causality.  I also display the examples of false causality on the flip chart and the ones we created together during our guided practice.  The samples will keep students focused o their tasks and give them a starting point from which to create their own products.

I explain to the class that we are making a class book.  So, each pair of students will work on a page of the book entitled:  False Causality Exemplified.  One person is the illustrator and the other the author of this page. Then, I gradually release the responsibility of working together to produce a page of this book to the students.  I facilitate as needed, while students work independently. Since students are just introduced to this concept, I feel that students still need peers to collaborate with and support one another.  Having each pair creating a page of a book requires a collaborative effort.

Sharing What We Learned

20 minutes

Students shared their ideas during our False Causality presentation and received feedback from classmates.  Many of their ideas came from personal experiences, either in the classroom or at home.  Students use their graphic organizers as visual aides to explain the fallacy in reasoning exemplified  in their false cause student sample.  Sharing ideas and having collaborative discussions facilitated the learning process.

It is important to create a collaborative classroom climate.  I start nourishing this supportive environment by introducing norms and rules so students know my expectations.  Giving peers constructive feedback is a learned process.  My class has been putting into practice giving quality feedback using a Giving Feedback Rubric to monitor their progress.  Using the rubric guides the types of feedback required for effective formative assessment.  Students understand that the purpose of feedback is to strengthen their skills, not to criticize.