Avoiding Fallacious Reasoning: Lesson 1

This lesson is taken directly from chapter 5 in Lewis Vaughn’s Writing Philosophy. It’s a short chapter with only 10 pages, but it’s one of the most important because it’s a quick survey on the most common fallacies, and committing anyone one of these fallacies automatically derails an argument. Obviously, you should read the chapter before doing this lesson, but for those of you who don’t have Vaughn’s text on hand, I’ll make sure to provide the necessary information to understand chapter 5.

The text I’ll be using:

Vaughn, Lewis. Writing Philosophy. New York: Oxford University Press, 2006.

A quick search on amazon or google will give you the necessary information should you want to own a copy.

Note on citations: I’m using a a very lax method on citations, so it’s not really meeting the standards in an academic setting. Indenting, for example, can’t easily be done on this website.

Important note about the embedded windows:

This website is designed for learning languages, so the window with the prompt "Translate this" serves as prompt/challenge command to the user. I don’t have the necessary tools to change "Translate this", so when you see "Translate this" just think of it as a command to enter in the correct answer. Also, use the correct grammatical number (singular or plural) when entering in the answer because if you don’t, you won’t get the “correct” text appearing after your answer. This, however, is not a big deal because what matters is if you understand Vaughn’s material.

So let’s begin.

The title of this lesson is “Avoiding Fallacious Reasoning”, which is the topic of chapter 5. Vaughn also covers fallacious reasoning in chapter 2, but the type of fallacious reasoning in chapter 2 deals with formal fallacies. The fallacious reasoning in chapter 5 are called material fallacies because they deal with, as Kreeft, a professor of philosophy at Boston College, puts it, “mistakes in the content or matter or meaning” (Socratic Logic 68).

It’s important to know that material fallacies are not mistakes in the logical form. Only formal fallacies deal with the logical form.

Note: Fallacies in chapter 5 are referring to material fallacies, and “material” is dropped out for the sake of brevity.

"The statement meant to be supported is the conclusion; the statements meant to do the supporting are the premises" (85).

Translate this: < click on this button afterwards to find out the correct answer
Your answer:

"The premises are supposed to be the reasons for accepting whether the arguments you encounter are good ones" (85).

We all want our conclusions to work out, but to do that we need to have our premises avoid fallacies.

"Fallacies are common but bad arguments. They are defective arguments that appear so often in writing and speech that philosophers have given them names and offered instructions on how to recognize and avoid them" (85).

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Fallacies don’t just have to be bad arguments; they can also be what Vaughn calls “deceptively plausible appeals.”

In chapter 5 Vaughn covers 13 different fallacies; it’s these 13 fallacies that are going to be covered.

Straw Man

A straw man is easy to knock down, as are weak arguments. According to Vaughn, “the straw man fallacy is the misrepresentation of a person’s view so he or she can be more easily attacked or dismissed” (86).

It’s important to fully understand your opponent’s argument before you debate it because otherwise you’ll likely be guilty of the straw man fallacy. A common straw man fallacy, writes Kreeft, is "when Rationalists have ‘refuted’ empiricists by noting that man is not merely a clever animal, the eye is not merely a camera, and the brain is not merely a computer. Only an extreme empiricist would hold that. And empiricists have ‘refuted’ rationalists by noting that man is not a god or an angel and that babies are not born with innate ideas. Only an extreme rationalist would hold that. E.g. there is a story that the poet Shelly, coverted to Platonic rationalism by reading Plato’s dialogues, rushed out of his house onto London Bridge, snatched the first baby he saw from its mother’s arms, and demanded of it an account of all the innate ideas it had been born with. Alas, the baby only cried" (80).

Translate this: What sort of fallacy is used when a rationalist tries to refute an empiricist by saying, “My brain doesn’t work like a Mr. Coffee with bells and whistles”
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Appeal to the Person

According to Vaughn, the appeal to person is “the rejecting of a statement on the grounds that it comes from a particular person, not because the statement, or claim, itself is false or dubious” (86).

Ad Hominem is also known as the appeal to the person.

Genetic Fallacy

An offshoot of appeal to the person is the genetic fallacy. Some logic textbooks have the genetic fallacy as a branch of ad hominem, but Vaughn separates ad hominem and genetic fallacy by having the genetic fallacy meaning, “the truth of the statement is supposed to depend on origins other than an individual – organizations, political platforms, groups, schools of thought, even expeptional states of mind (like dreams and intutions” (88).

Right, so ad hominem is strictly towards a person, and the genetic fallacy is dependent on “origins other than an individual.”

In the following exercises, which were taken from various texts, determine which fallacy is being used.

Translate this: The U.S. Senate is considering a proposal to reform affirmative action, but you know their ideas must be ridiculous. What do they know about the rights of the disadvantaged? They’re a bunch of rich, white guys.
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So far 3 out of 13 fallacies have been covered. When all 13 are covered, the exercises will become more challenging, as it will force the learner to discern which of the 13 fallacies is being used.

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