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3.2 Fallacies Of Relevance


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Course lecture I developed over section 3.2 of Patrick Hurley\'s "A Concise Introduction to Logic".

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3.2 Fallacies Of Relevance

  1. 1. 3.2 Fallacies of Relevance
  2. 2. Overview <ul><li>Understanding fallacies of relevance </li></ul><ul><li>Identifying different forms of these fallacies </li></ul>
  3. 3. What is a fallacy of relevance? <ul><li>A fallacy of relevance is one where the argument in which it occurs has premises that are logically irrelevant to the conclusion. </li></ul><ul><li>They appear to make sense though which makes them difficult to identify. </li></ul><ul><li>What is flawed about an argument with a fallacy of relevance is that the connection between the premises and conclusion is emotional . </li></ul><ul><ul><li>To recognize this kind of fallacy, you need to be aware of the difference between arguments that use genuine evidence and those that rely on an emotional appeal. </li></ul></ul>
  4. 4. Identifying fallacies of relevance <ul><li>Appeal to force (ad baculum) </li></ul><ul><ul><li>Occurs whenever an arguer puts forth a conclusion and either states or implies that if the listener does not agree then he will somehow be harmed. The threat can either be physical or psychological. </li></ul></ul><ul><ul><li>Examples: </li></ul></ul><ul><ul><ul><li>“ Either agree that I’m king of the world or I’ll beat you up!” </li></ul></ul></ul><ul><ul><ul><li>“ Give me $200 or I’ll tell your wife you’re cheating on her.” </li></ul></ul></ul><ul><li>Appeal to pity (ad misericordiam) </li></ul><ul><ul><li>Occurs when an arguer tries to support a conclusion by getting pity or sympathy from the listener. </li></ul></ul><ul><ul><li>Examples: </li></ul></ul><ul><ul><ul><li>“ Don’t give me a ticket, officer. My wife has cancer and my aunt just had a stroke!” </li></ul></ul></ul>
  5. 5. More fallacies <ul><li>Appeal to the people (ad populum) </li></ul><ul><ul><li>The arguer manipulates the values and beliefs of people in order to make them believe a certain conclusion. </li></ul></ul><ul><ul><li>There are two ways of doing this: </li></ul></ul><ul><ul><ul><li>Direct approach </li></ul></ul></ul><ul><ul><ul><ul><li>An arguer addresses a large group of people and tries to excite them and make them emotionally charged, so he can win their acceptance for his argument. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Examples: various politicians </li></ul></ul></ul></ul><ul><ul><ul><li>Indirect approach </li></ul></ul></ul><ul><ul><ul><ul><li>Arguer does not focus on the crowd itself but at certain people and how they relate to the crowd as a whole. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Bandwagon argument – If you don’t go along with the argument, you’ll be left out. Persuaded to join in, so you can be a part of the crowd. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Appeal to vanity – Argument that compare you with someone that is admired or pursued, and if you agree then you’ll be admired too. </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Appeal to snobbery – Similar to vanity, since it implies that you’ll be a part of an elitist crowd if you go along with the arguer. </li></ul></ul></ul></ul>
  6. 6. More fallacies <ul><li>Argument against the person (ad hominem) </li></ul><ul><ul><li>One person makes an argument, and the other person replies with a criticism but not one made about the argument, but about the person himself. </li></ul></ul><ul><ul><li>Ad hominem abusive </li></ul></ul><ul><ul><ul><li>Standard ad hominem argument, where the second person criticizes the arguer instead of his argument. </li></ul></ul></ul><ul><ul><ul><li>Example: </li></ul></ul></ul><ul><ul><ul><ul><li>“ John says I should quit smoking because it’s bad for me. But he’s practically an alcoholic, so who is he to give me advice about my health?” </li></ul></ul></ul></ul><ul><ul><li>Ad hominem circumstantial </li></ul></ul><ul><ul><ul><li>Similar to ad hominem, except the second person criticizes circumstances or conditions surrounding the arguer. </li></ul></ul></ul><ul><ul><ul><li>Example: </li></ul></ul></ul><ul><ul><ul><ul><li>“ You just want me to break up with my girlfriend so you can ask her out!” </li></ul></ul></ul></ul>
  7. 7. More fallacies <ul><ul><li>Tu quoque (you too) </li></ul></ul><ul><ul><ul><li>The second person criticizes the arguer for acting like a hypocrite or for arguing in bad faith. </li></ul></ul></ul><ul><ul><ul><li>Example: </li></ul></ul></ul><ul><ul><ul><ul><li>“ You’re one to yell at me about being messy. Your bedroom looks like a pigsty!” </li></ul></ul></ul></ul><ul><ul><ul><li>But remember, there are times when a criticism against a person can be properly backed up. </li></ul></ul></ul><ul><ul><ul><ul><li>“ You lie, you cheat on your wife, and you steal cars. Therefore, you’re a bad person.” </li></ul></ul></ul></ul><ul><ul><ul><ul><li>The main point here is that the second person is bad, not that his argument is bad, and the premises here (his behavior) are supportive of the conclusion, so no fallacy is committed. </li></ul></ul></ul></ul>
  8. 8. More fallacies <ul><li>Accident </li></ul><ul><ul><li>Fallacy that is committed when a general rule is applied to a specific case it was never meant to cover. </li></ul></ul><ul><ul><ul><li>Example: </li></ul></ul></ul><ul><ul><ul><ul><li>“ Guns are responsible for many accidental deaths. Therefore, they threaten the lives of police officers for carrying them.” </li></ul></ul></ul></ul><ul><ul><ul><ul><li>Police officers use guns as a way of maintaining peace, and this belief does not cover them and their role in society. </li></ul></ul></ul></ul><ul><li>Straw man </li></ul><ul><ul><li>An arguer distorts his opponent’s argument then defeats that changed argument. He then concludes that he has defeated the original argument as well. </li></ul></ul><ul><ul><ul><li>Example: </li></ul></ul></ul><ul><ul><ul><ul><li>“ Many people stand in support of women’s rights. They argue it’s a woman’s right to choose whether to have an abortion, but abortion is murder. How can these people defend murder?” </li></ul></ul></ul></ul>
  9. 9. More fallacies <ul><li>Missing the point (ignoratio elenchi) </li></ul><ul><ul><li>In this fallacy, the premises actually support a conclusion, but a different conclusion than the one presented in the argument. Usually, it’s possible to figure out the correct conclusion since it is what actually follows from the premises. </li></ul></ul><ul><ul><li>Example: </li></ul></ul><ul><ul><ul><li>“ American prisons are becoming overpopulated. That means we need to start executing more people to get more space!” </li></ul></ul></ul><ul><ul><ul><li>The logical conclusion for this argument is that we need to either build more prisons or find different ways to rehabilitate prisoners, not that we need to kill more people. </li></ul></ul></ul><ul><li>Red herring </li></ul><ul><ul><li>This fallacy involves changing the subject of an argument to a slightly different topic, to throw the other person off. Then a conclusion is drawn based on this altered argument. </li></ul></ul><ul><ul><li>Example: </li></ul></ul><ul><ul><ul><li>“ People say that fast food is cheap and not hard to get. But family dinners are an important part of keeping a household together. Without quality time, most families would fall apart! Parents need to shift gears and take action if they want to stay in touch with their kids.” </li></ul></ul></ul>