### 3.4 Fallacies in Logic

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• Math Help

In Example 5, notice that the syllogism is valid. The problem with the argument is not that the conclusion does not follow from the two premises. The problem is that the first premise is not valid. With many celebrity endorsements, it is also quite possible that the second premise is also not valid.

 • Premise: If Marilyn Monroe uses a product, then you should use it. • Premise: Marilyn Monroe uses Lustre-Creme shampoo. • Conclusion: Therefore, you should use Lustre-Creme shampoo.

Appeal to authority can be a valid form of logical argument. It is less often true that an appeal to celebrity is a valid form of logical argument. Notice that to be valid, an appeal to authority or celebrity should pass the following criteria.

1. The authority has competence in the area, not just popularity.
2. The judgement must be within the authority's expertise.
3. The authority must be interpreted correctly.
4. Direct evidence is available.
5. A technique is needed to settle disagreements between equally qualified authorities.
• Consumer Suggestion

If you have an interest in vintage advertisements like Marilyn Monroe's Lustre-Creme ad, you might want to check out Found in Mom's Basement, a blog featuring vintage advertisements from as early as 1900.

• Checkpoint Solution

Whether you agree or disagree with this policy depends on your political philosophy.

If you believe that it is the government's responsibility to protect citizens from making bad decisions or bad choices, then you probably agree with the policy. Just because something is foolish or harmful, is it the responsibility of the government to make it illegal?

On the other hand, if your political philosophy is that the primary responsibility for making good decisions and good choices lies with the individual, then you probably disagree with this policy. Historically, the philosophy of "Buyer Beware" was part of early America. As the country grew, however, the government felt more and more compelled to protect citizens. One small instance of this is the rules and regulations that a restaurant must comply with to be licensed to prepare and sell food.

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Cody (moderator)10 years ago |
There is a fine line between fallacies in advertising and just plain old false advertising. Companies that cross that line often find themselves in danger of being sued. To read about a company that is currently facing a false advertising lawsuit check out the "math in the news" section of our blog.

http://www.andyou.com/blog/math-in-the-news/math-in-the-news-fallacies/
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