informal reasoning 1/9. agenda  introduce informal reasoning  reflect on informal reasoning...

Download Informal Reasoning 1/9. Agenda  Introduce Informal Reasoning  Reflect on Informal Reasoning  END GOAL: Is informal reasoning reliable?

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Informal Reasoning

Informal Reasoning1/9AgendaIntroduce Informal ReasoningReflect on Informal Reasoning

END GOAL: Is informal reasoning reliable?Question 1What is the difference between a prejudice, a generalization, and a scientific law?Informal ReasoningPost hoc ergo hocAd hominemCircular ReasoningSpecial PleadingEquivocationAd IgnorantiamFalse AnalogyFalse DilemmaHasty GeneralizationLoaded QuestionsPost hoc ergo propter hocLiterally, after this, therefore on account of thisBecause one thing (b) follows another thing (a), then A must be the cause of B.EXAMPLE:Murder rate goes up after abolition of the death penalty. Therefore, getting rid of the death penalty increased the murder rate. FLAW: it COULD be the case, but it might not bePost hoc ergo propter hocEven when one event USUALLY follows another, it is still does not NECESSARILY mean the two are connected.CAREFUL: claiming something is a fallacy when notTobacco CompanyCasual Connection vs. Fallacy (red wine and heart)Ad hominemLiterally: Against the manAttack/Support the person rather than the argument (VESTED INTEREST)Rather than critique an idea or argument, a person is being attackedUSUALLY used to attack someone, but can also be done to support.Einstein liked it, so it has to be good!

Question 2Are we ever justified in rejecting what someone says solely on the basis of who they are?Circular ReasoningYou assume the truth of something that you are supposed to be provingWhat at first looks like an argument is really just a reassertion of their positionEXAMPLE: I know that Jesus is the Son of God because he said he was, and the Son of God would not lie.Special PleadingDouble standard making an exception in your own case that you would not find acceptable for someone elseExample: I know there is a drought and we need save water.but MY flowers are prize winning daffodils! EquivocationSyllogisms with different senses/meaningsA hamburger is better than nothingNothing is better than good health.Therefore a hamburger is better than nothing.Two different definitions of nothing (not having anything vs. there is not anything)Ad IgnorantiamSomething is true on the grounds that there is no evidence to disprove it

Loch Ness MonsterBog Foot?False AnalogyAssume that because two things are similar in one respect they must also be true in other waysJust as in time the gentle rain can wear down the tallest mountains, so, in human life, all problems can be solved by patience and quiet persistence.False DilemmaThe fallacy of deciding there are only two options, when in reality there are a wide range of possibilitiesDo those who advocate an increase in military funding what to see schools and hospitals close?Loaded QuestionsA question that contains a built in assumption that has not been justified and may be false.

Do you always cheat on exams?Can be a statement: That teacher was not drunk today.Quote 1Whats so fascinating about New Yorkers is that each person has a whole lexicon of personal logic in the way that they decipher and do what has to be done to enjoy, stay alive, take pleasure in this place. Spalding Gray

What does this quote mean?Is it true only of New Yorkers?

Quote 2When dealing with people, remember you are not dealing with creatures of logic, but creatures of emotion. Dale Carnegie

What does this quote mean?Agree/Disagree?How does this quote and your position on it affect your answer to yesterday question about perception vs. reasoning?

Quote 3All of our reasoning ends in surrender to feeling. Blaise Pascal

What does this quote mean?Do you agree or disagree?What are some examples you see in our society/in your own life?


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