Common Fallacies

Mistakes in Reasoning

Chapter 6

THREE LOOK-ALIKE MISTAKES

Argument from Popularity

Argument from Common Practice

Argument from Tradition

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“Argument” from Popularity “Everybody believes X.

Therefore X is true.” Example:

“Everybody thinks God exists. Therefore, God exists.”

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“Argument” from Common Practice

“Everybody does X. Therefore it’s right to do X.”

Example:

“Everybody breaks the speed limit. Therefore, it’s right to break the speed limit.”

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“Argument” from Tradition “Thinking or doing X is a tradition.

Therefore it’s right to think or do X.” Example:

“Traditionally marriage has been restricted to heterosexual couples. Therefore it’s right to restrict marriage to heterosexual couples.”

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“Arguments” from Popularity, Common Practice, and Tradition

1. Everybody believes X.Therefore X is true.

2. Everybody does X.Therefore it is right to do X.

3. X is a tradition.Therefore it is right to think or do X.

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TWO MORE LOOK-ALIKE MISTAKES

Scare Tactics

Argument from Force

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Scare Tactics Trying to scare us into accepting or doing

something. Example:

“Buy Michelin tires. Don’t risk your children’s safety by buying inferior brands.”

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Argument from Force Trying to threaten us into accepting or

doing something Example:

“Buy Michelin tires, or I will see to it you lose your job.”

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STILL TWO MORE LOOK-ALIKE MISTAKES

Group Think

Peer Pressure

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Group Think Trying to get us to do or believe

something by appealing to our pride of membership.

Example:

“Buy Michelin tires! We all work for Michelin and belong to a very special company!”

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Appeal to Nationalism or Patriotism—forms of Group Think

Trying to get us to do or believe something by appealing to our pride of membership in a nation or state.

Example:

“Of course we are winning the war! We are the best country in the history of the world!”

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Peer Pressure Trying to get us to do or believe

something by appealing to fear of being excluded from the group.

Example:

“Of course we are winning the war! If you don’t like it here, move to Baghdad, you weirdo!”

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Group Think v. Peer Pressure

Group Think (including Nationalism and Patriotism) plays on our pride of belonging to a group.

Peer Pressure plays on our fear of being excluded from a group.

Real-life cases often include a blend of the two.

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TWO OTHER LOOK-ALIKESRationalizing

Wishful Thinking

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Rationalizing Lying to ourselves about our real reasons

for believing or doing something. Example: Buying your wife a battery

charger for her birthday: “She can really use this!”

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It’s also a fallacy to try to get someone else to rationalize.

“Buy your wife a battery charger! She will really be able to use it!”

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Wishful Thinking Thinking X is true for no better reason

than you want it to be true. Denial is a common form.

“Oh, Professor Moore, I didn’t miss THAT many classes!”

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NUMBER FIVERed Herring/Smokescreen

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Red Herring/Smokescreen An irrelevancy brought in to “support” a

claim or to distract one from the issue Technically, many are Red Herrings. But we will use “Red Herring” to refer to

irrelevancies we cannot put into one of our other categories.

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We will make no distinction between a “Red Herring” and a “Smoke Screen”

Example of a Red Herring:

“Yes, of course the President’s strategy in Iraq is working. The Democrats sure haven’t come up with anything better!”

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Another example of Red Herring

“Yes, obviously the President’s strategy in Iraq is working. The liberal media in this country just can’t stand the thought of us winning this war.”

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It’s also a Red Herring if you change the subject to avoid answering a question:

“Why do I oppose gay marriage? I guess it was the way I was brought up.”

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Assorted emotional appeals: Argument from outrage Argument from pity Argument from envy Apple polishing

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LAST TWO:

Two wrongs make a right

Relativist fallacy

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Two Wrongs Make a Right Thinking wrongful behavior by someone

else excuses wrongful behavior by you Thinking another would do a wrong to you

excuses doing wrong to him/her

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Relativist Fallacy: believing both of these at the same time:

It’s wrong to do X. It’s not wrong to do X, if your society

thinks it is okay to do X.

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Relativist Fallacy Example: “Well, I think human sacrifice is immoral,

but the ancient Mayans didn’t, so it wasn’t wrong for them.”

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