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Logic and Fallacies

Added Sep 22, 2013 •

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Watch this video to learn about logic and fallacies! Then avoid using fallacies from henceforth.

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high class today we're going to talk about logic and fallacies  we're going to discuss two different types of reasoning the first is deduction or deductive and this is the process of moving from a general rule to a specific example so you start with a Max and that's already been accepted and then based on that you can reach specific conclusions so one example is the general rule that the greatest president of all time President Bush Washington always and so therefore if you play with him against him and weird with Words With Friends he's going to win so there was a general rule that he always and in a specific instance you're able to reach a specific conclusion another example is that since oranges are fruits and fruits grow on oranges grow on trees look at them okay the office it is in Shan or inductive reasoning and this moves from a given series of specifics to a general conclusion so it's opposite you're going from really specific things and then getting General Casper came to say hi what's the or my mouth swells up when I clams and shrimp triggers my asthma I might reach the general conclusion that I'm allergic to shellfish so where as deductive reasoning is foolproof assuming the premises are true inductive reasoning always has an element of uncertainty because you can't see all of the various specifics but it is used to when you write essays you're using inductive reasoning because you're bringing in quotations from the book to prove a general or more General point which is your thesis a syllogism is a specific type of deductive reasoning and it's from the Greek for Reckoning together but basically system of formal logic and you start with two major premises one that's major so that's going to be your general that you're starting with and one that's and then they will inevitably lead to a sound conclusion so the example that's always given his all men are mortal so that's her major promise it's a general Socrates is a man therefore Socrates is mortal  an enthymeme is what you'll encounter more often than its syllogism when 18 essays were listening to speeches it's an informal syllogism in which one of the premises is unstated or assumed so you have the major promise in the mine promise for one of those I don't talk about it because I assume that my audience thinks that way and so I don't need to say it I'm so it depends on the audience is agreements with the Assumption so free sample if I said we better cancel the picnic because it's going to rain that's because it's assuming several promising that picnic outside your life up the rains going to affect them assuming that rain is bad weather and that when the weather is bad it's best to cancel picnics and that a 70% chance of rain which is what I saw on the news means that rain is more likely to occur with a knot and that when rain is more likely to occur than not it makes sense to cancel picmix it's assuming all of those things and assuming that my audience knows those things unless I don't need to state that these will also be called warrants when we get to different argument Styles but we won't cover that until next semester here are some other logic terms that I'm sure you're familiar with so I just wanted to review very quick an example it's an instance taken to be representative of a general pattern you offer examples to make your arguments but if you do you have to carefully pick examples that do represent the norm and then I'll tell a claim and that is an assertion of something as as fact but you must back up your claims with support a generalization is when you base name on an isolated example or a few examples and rebuttal or refutation is when you deal with opposing arguments anticipate that people might say something and so you bring it up idler did that a lot when he wrote how to Mark a book now we're going to get into logical to start off with a fallacy is an argument that supplied by its very nature and often it just a little floss legitimate form of appeal so they're using rhetoric about the ethics of the argument they make us wonder if argument is being honest if the person speaking is principles fallacies can destroy your ethos because it looks as if you as a speaker is dodging the or shifting fax but it's also very much current is not going to seem logical logical fallacy  so one type of fallacy is to either or fallacy and what it does when are very complex World it reduces the options for Action to only two choices of course in doing that similar to antithesis make one option really awesome in the other. Horrible  so when George W bush says our troops know that they're fighting in Iraq and Afghanistan password protect their fellow Americans from a Savage enemy they know that if we do not confront these evil men abroad we will have to face them ones in our own cities and Street not he's creating an either or fallacy he's suggesting that there are only two possible options very complex issue of terrorism turn up brightness in the streets ignores other potential are there things that politicians and great leaders would know that I don't have to when and Beauty and the Beast Gaston is like here either with us or you're against us and so he's making it just decided our human no one that is allowed to be like  Play would it be to attack him with a large the next one is faulty causality and in Latin the phrase for this is post hoc Ergo propter hoc which means for because of this is because one thing happened and then another thing happened after it cost II always look like that right so example is I think I completely made examples don't do that their program 1980s therefore they're fails and in fact causes teens to drink alcohol so because one thing happens to DARE program started and then another thing happens more teams admit Thunder drinking this is arguing that this is a direct cause of that which is unfair it could be that more teams are being honest and drinking you know video games it's always says video games are example is that I resurface and the sun rises and so then people start to think that that room has the power to make the sunrise it caused it on that is not true one of the most common in conversation faulty causality asthma people jokingly say I washed my car so it's going to rain  okay I'm so excited to tell you about this one so then I can get all over your papers because you guys have been using it a lot circular reasoning or begging the question it is when as the premise for the arguments you say it conclusion so basically you repeat the same thing in slightly different words and pretends that that's making an argument so it's an attempt to support a statement by your one statement that okay so if it student said you can't give me a C I'm an a student that's saying the same thing right it's not making an argument and a student would not get a c and so then you would be unable to give them a seat but that doesn't they're the same thing or if residence the great President Bush Washington if he said women have a right to choose whether to have an abortion or not there for you should be allowed that saying the same thing right if abortion is allowed then women have a right to choose so it's not actually making the argument you guys use that a lot some of you that was a generalization I'll get to that soon  next wow so Hasty generalization is an inference drawn from insufficient evidence so the fact that I've noticed circular reasoning in about  theory of the 50 essays that I just read and then felt as if I could generalize about all of my Vince was Hasty his that was insufficient evidence other examples are because my Honda broke down then all Hondas must be that's just one Honda maybe all the other Hondas are great and then of course stereotyping people and example to follow say there's this person and then she comes and there's like that cord there because she's about to fix a computer and someone says it's just you don't look like an engineer why isn't that what Engineers look like the next one is faulty analogy I know we talked about faulty causality that one has caused in it so it's the order things happen faulty analogy is about comparison so an analogy that isn't necessarily faulty is an extended comparison between two things to help people San an unfamiliar concept by comparing it's something that's familiar that's okay because like many fallacies faulty analogy starts with something that Batman kind of stretches it a little too far I'm so an analogy is faulty when it's an inaccurate or inconsequential between objects or concepts from everyone's favorite faulty analogy right now is comparing various presidents to Hitler so here we have a Graphic comparing Obama to Hitler here we have some photoshop presenting President Bush to hit Casper's I'm being helpful and then even the great President Bush Washington has been compared to Hitler forward back to that they're not beating the massacre of milia what people  because of racist ideals alright then bandwagon appeals you I'm sure I learned about these possibly in a dare program when you were in junior high and their arguments that are rich people to follow the same path everyone else is taking my nations are messed up because that McDonald's should have here in a second but first McDonald's advertising by saying billions and billions and billions served suggest that does billions of people are eating their burgers that somehow says that their burgers are good or something about the quality of their burgers  Casper's S5 example it's going to be covered up is from its a picture of the website for no on Prop 8 19 I think Prop 19 news about legalizing marijuana in California and it has that image of all the people that oppose Prop 19 in order suggest that well all those people opposed it so should you argument ad hominem means to the man and not when set of arguing get someone's points you attack the character of that person so if someone were to say it's no wonder he support tax cuts he's loaded this is ignoring that the person who doesn't support tax cuts may have policy decisions may know things about nomics that makes him think that tax cuts won't be helpful it ignores all of the policy thinking in the person's argument and it's just argument based on the fact that has money and then one that you may have heard the people like to throw around is all well I used to think that when I was age and that's totally an argument against you solely based on your age it's ignoring what you have to say and suggesting that your son now more ignorance because you're younger and that disqualifies you from making an appropriate arguments and not faced on you on your argument fallacy another great fallacy is straw man fallacy and it's attacking an argument that is so instead of attacking what your opponent is actually saying you build a little strong man to attack because they're easier and they don't fight back I'm so you give them a week or indefensible position that they don't hold but that's kind of close to a position that they hold so then you can defeat it sober Obama home said in a speech we can no longer afford indifference to suffering outside our borders I don't remember what he was trying to convince the American people to do but I have a feeling that those who opposed his policy we're probably not having the policy Fair outside our borders we don't care about them but he reduced their arguments to that because it's easy to fight against that when's another example is when people say that evolutionists believe that humans evolved by chance how could complex organisms like the eye of all from Champs that's reducing the arguments to something like the role of a dice where was far more complicated than that  NN slippery slope slippery takes advantage of the notion that one thing leads to another so it's you know cause and effect but it exaggerated the likely consequences of an action to frighten people I'm so many of you do this all the time when you think oh my gosh if I fail this test then I'm can you get a be in this class if I get a be in this class I will lower my GPA and then I won't be able to compete with other people that are applying to the same school as me and so I won't get into the high-level college that I want to get into you and then if I'm not in the best college then I'm not going to get into medical school and it's just a slippery slope another example is someone says if we legalize gay marriage soon humans will be marrying animals turn kind of our general policy on some of these are specific examples of non sequitur and of course if you're given the option play some of specific example but another General fallacy is non sequitur which means it does not follow so that's an argument in which claims reasons are warrants built watch one point doesn't follow another so for instance if two years ago I said to my husband not love me because you haven't bought me a puppy that would be non sequitur because buying a puppy does not directly relate to his love similarly if now I was like my husband loves me because he bought me a puppy I either have a really really small Dia of what love means arts and non sequitur a more complicated example is if someone says American students are poorly in international mathematics examinations so therefore the US should spend more money on mathematic education that's the solution is spending more money it could be reprioritize e'en what matters American students it could be better training for teachers it could be any 10-year there are variety of things and if this person what's to make that claim they better offer a lot of support so that they prove that those to follow because as it is right now it does so that brings us to the end of our fallacy PowerPoint go out there and use Rudder well

Uploaded by Melissa Rhoades-Rudder '01.

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Logic and Fallacies

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