Non Sequitur: When Conclusions Don't Follow

What Is a Non Sequitur?

A non sequitur is a formal fallacy where the conclusion does not logically follow from the premises. The term "non sequitur" is Latin for "it does not follow." This fallacy occurs when there is no clear connection between the argument's premises and its conclusion, making the reasoning invalid.

• Structure:

  • Premise 1: P.

  • Premise 2: Q.

  • Conclusion: Therefore, R.

The lack of logical relationship between the premises and the conclusion renders the argument incoherent or irrelevant.

Examples of Non Sequitur

1. Everyday Example:

   • Premise 1: She’s a great dancer.

   • Conclusion: She must be good at math.

   • Why It’s a Fallacy:
     Dancing ability has no logical connection to mathematical skills.

2. Business Example:

   • Premise 1: Our company had record sales last year.

   • Conclusion: Therefore, we don’t need to market our products this year.

   • Why It’s a Fallacy:
     Success in the past doesn’t guarantee future success without continued effort.

3. Social Example:

   • Premise 1: I love chocolate.

   • Conclusion: Therefore, I’ll be a great musician.

   • Why It’s a Fallacy:
     A preference for chocolate has no bearing on musical talent.

Why Is This a Fallacy?

Non sequitur arguments fail because they lack a logical bridge between the premises and the conclusion. Even if the premises are true, the conclusion does not logically follow, making the argument invalid.

How to Avoid Non Sequitur Fallacies

1. Ensure Logical Relevance:

   • Verify that the conclusion directly follows from the premises.

2. Check for Missing Steps:

   • Look for any implicit assumptions or unspoken connections that need to be stated explicitly.

3. Use Clear Reasoning:

   • Each premise should contribute to the conclusion in a logical and meaningful way.

Quiz: Test Your Understanding

1. Question 1:
   Is this a non sequitur?

   • Premise 1: John is tall.

   • Conclusion: John must be good at basketball.

   • Hint: Does height necessarily correlate with basketball skills?

2. Question 2:
   Identify the flaw:

   • Premise 1: Our team has the best players.

   • Conclusion: Therefore, we’ll win the championship.

   • Why might this reasoning be invalid?

3. Question 3:
   Which of the following avoids a non sequitur?

   • A) "She enjoys reading books; therefore, she must dislike movies."

   • B) "She enjoys reading books; therefore, she’s likely knowledgeable about literature."

Conclusion

The non sequitur fallacy reminds us of the importance of clear and logical connections between premises and conclusions. By ensuring that our arguments follow a logical progression, we can avoid making irrelevant or incoherent claims.