Lecture 2.1 INTRO TO LOGIC/ ARGUMENTS. Recognize an argument when you see one (in media, articles, people s claims).

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1 TOPIC: You need to be able to: Lecture 2.1 INTRO TO LOGIC/ ARGUMENTS. Recognize an argument when you see one (in media, articles, people s claims). Organize arguments that we read into a proper argument outline. Identify characteristics of an argument: premise, conclusion, assumptions, and consequences, conditional statements. KEY TERMS/ GOALS: Definitions: Argument Proposition Premise Conclusion Conditional statement (including antecedent and consequent. ) READING: Download: Monty Mython s Argument Clinic at: (there is a written transcript under Handouts folder if you want to read the script). Perry, Logical Toolkit p Vaughn, Chapter 2 (on E-reserves) Reasoning Tutorial (under Handouts folder). You only need to read one or two. You will be asked to summarize one of these articles on the exam. CONTENT: Welcome to the most technical and probably difficult week in this class. Logic and critical thinking may come easy to some of you, but it might be frustratingly difficult for others. The important thing to note is that the lectures for this week are atypical of the material we will be studying for the rest of this class, so do not panic if you do not feel like you understand. Being able to recognize and outline arguments in deductive and inductive forms take practice. To foreshadow, we will be examining different types of arguments: Deductive and Inductive arguments are the general kinds of arguments. Then there are a number of common types of arguments, and we will look at authors that employ Inference to the Best Explanation and Reductio ad Absurdum arguments in the course of the semester. The next lecture (2.2) focuses on Deductive arguments and you will be able to identify the difference between valid and invalid forms of deductive arguments. Next time we will also look at Inductive arguments. In

2 the last lecture (2.3) we will look at Informal Fallacies, which are common mistakes people make. Your Critical Thinking Assignment will be on Informal Fallacies. This lecture will introduce the definition of an argument. Why are we learning Logic? The short answer to why we are studying logic (as a first topic) is that without a common structure to assess whether arguments are good or bad, then reading and hearing people s claims will just be a mess. You might feel like philosophers go around in circles if you do not pay attention to very subtle arguments being made. Philosophy trades on people s ideas, and back and forth dialectic on various topics. Philosophers often make original ideas that are often (seemingly) subtly different than their opponent s ideas. Because ideas are subtle, you need to be able to read carefully and distinguish between the arguments. This involves being able to recognize arguments and organize them into argument outlines. Another answer to why logic is important is that without the ability to think critically, you may be caught up in bad schemes and make bad decisions (in business, politics, ethics, etc.). We live in a capitalistic society, and to be responsible consumers, we need to be able to know when advertisers, for example, are feeding us BS. Learn to recognize a bad argument when you see one. We also live in a Democratic society, and our role as citizens demand that we be able to assess politicians clams. Recall from last week s lectures that Russell thought that the value of philosophy is that it stops you from being a slave to conventions or to other people. In other words, if you simply take other people s word and do what they say, then you are simply a slave to other s values. No one (I hope) wants to be in this position. But in order to assess what others say and see if you believe in those claims, then you need to be able to think critically. Thinking critically does not mean simply disagreeing with everyone, it means being able to evaluate arguments and assess whether they are good arguments. The third reason logic is important is that you don t want to make bad arguments yourself, do ya? In order to analyze people s claims (including your own beliefs) you must know how to structure them, and be able to tell if these beliefs are valid, sound, strong, etc. Examine your own beliefs and find the best reasons to hold those beliefs. If you find that your beliefs are not justified, then don t be afraid to consider changing your beliefs. Recall that Socrates advises people to examine themselves ( the unexamined life is not worth living ). One reason we considered is that examination (or inquiry) motivates one to learn new things, which is what growth is all about. You can also read this quote as saying that if you do not examine your own beliefs, then you will dogmatically be stuck believing false things. What is an argument and how do you outline and argument? Philosophy is all about assessing people s arguments for why they think their theory or doctrine is true. It is about making claims and backing them up with good reasons and evidence. Anyone can make a claim, such as The world is round, but the reasons or evidence they give is what matters. If someone gives a reason such as I read it in the National Enquirer, then you might suspect the claim because the source is not a reliable one. If someone says The world is round because the Hubble telescope took pictures of the world and it was round, then the evidence is more reliable. There are a million different arguments (or reasons) to the same conclusion, so do not think that you understand someone s argument just because you agree or understand the conclusion. Philosopher s often give odd reasons to support their conclusion.

3 What is an argument? Monty Python has created a funny skit about what arguments are (and are not). Arguments are not simply contradicting your opponent. A contradiction is just an automatic gainsaying of any statement that another person makes, according to Python. So, don t think you are practicing your logic when you get into those I did not you did too brawls with your friends. An argument rather is a connected series of statements intended to establish a proposition (Python, 1972). Perry defines an argument as a series of statements where the last statement supposedly follows from or is supported by the first statements. There are two ingredients to an argument: A Conclusion, and one or more Premises to support the conclusion. Both the conclusion and the premise must be in the format of a proposition, which is a sentence that can be true or false. It contains a Subject (the subject of a sentence) and a Predicate (verb and object). Take the following proposition: My cat threw up her dinner. My cat is the subject, and threw up her dinner is the predicate. Statements such as Ouch, Stop it and Why did the cat throw up are not propositions. Let me repeat that: Questions are not propositions, and cannot be used in an argument. (I mention this because often students explain someone s argument by asking a question and then thinking the answer is obvious. If you ask questions in your papers, then be sure to answer it in proposition format. ) Now that we understand a proposition, take several propositions and turn them into an argument. If you say, My cat threw up her dinner because her dinner was old, then you have an argument. The first proposition My cat threw up her dinner is the conclusion. That is the statement that the author wants to convince you about, by giving a reason, namely that her dinner was old. We can outline the argument as follows: Premise: My cat s dinner is old. Conclusion: My cat threw up her dinner. The first statement is a premise because it is intended to support the conclusion (the last statement). Notice that in an outline, I had to reverse the order of the propositions. When you read articles, you must be aware that an argument is not always narrated in the form of an argument. Sometimes people state their conclusion first, and then provide their reasons. Sometimes people jump around, and provide a lot of details that are unnecessary to the argument itself. Often premises are long, especially when they give you evidence such as statistics or research. So, you must extract the argument from the written (or spoken) materials, to form an argument. This is no easy task, and it takes a lot of practice to extract arguments. I have outlined the argument above by separating out the premises and the conclusion. Often there will be several premises to a conclusion, but there will only be one conclusion to an argument. If you come across several claims that are being made in an article, then those are different arguments, each with their own reasons. How do you recognize an argument? The first thing you should do is figure out what the conclusion is. The conclusion will be what the author is trying to persuade you to believe. The premises, of course, are the reasons why the conclusion is supposedly true.

4 Let s take another example. Suppose I say: Lecture 2.1 INTRO TO LOGIC/ ARGUMENTS. It is good to take a philosophy class. It gets you up in the morning. I am trying to persuade you that it is good to take a philosophy class. Now for the premises, or the reasons why you might be persuaded that the conclusion is true. My reason is that It gets you up in the morning. So we can outline the argument as follows: Premise: Taking philosophy classes gets you up in the morning. Conclusion: It is good to take a philosophy class. The premise is used as evidence for the conclusion. In this case, the evidence is from empirical observation. Empirical evidence is based on observing things in the world. The reason we know that taking philosophy classes gets you up in the morning is because we (lot s of people) have seen that people get up in the morning to take philosophy classes. Notice, too, that it is not entirely clear why the conclusion follows from the premise. That is because we are missing an inference proposition which is a statement that connects the premise to the conclusion. We must fill in the inference which I put as the first premise, namely It is good to get up in the morning. I marked the premise as an unstated assumption, because although it is implied in the argument, the author did not explicitly state it. I hope you can see that it is an assumption to think that it is good to get up in the morning. I am assuming it, otherwise I would not try to persuade you that taking classes is good because it gets you up in the morning. If I did not think it was good to get up in the morning, then I would not persuade you to take philosophy classes for the reason that it gets you up. Here is our final outline of my argument: Premise 1: It is good to get up in the morning. (Unstated Assumption) Premise: Taking philosophy classes gets you up in the morning. (Empirical evidence) Conclusion: It is good to take a philosophy class. It is a good idea to mark where unstated assumptions are, but you don t have to mark whether premises are by empirical evidence. Vaughn gives an excellent list of indicator words that you should look for in articles. Indicator words signal when an argument is being made. Indicator words for conclusions: Consequently Thus Therefore As a result

5 Hence Indicator words for premises: --because --since --for --given that --the reason being For example, if you hear I don t like this gum because it takes like dirt, then you know the conclusion is the proposition that follows the word because, and the premise is at the beginning. Thus: Premise: My gum tastes like dirt. (Empirical evidence) Premise: I don t like anything that tastes like dirt. (Unstated assumption) Conclusion: I don t like this gum. Do not get premises and conclusions mixed up in your explanations of arguments. What are conditional statements? I talked about inference statements, which are premises that connect the premises to the conclusion. The easiest way you can connect them is by saying that if the premise is true, then the conclusion is true. Conditional statements are If-then propositions, namely statements that claim that if some cause happens, then some effect will happen. In the argument above, I can say that If my cat s dinner is old, then she will throw it up. This statement makes sense, and it connects a conclusion ( my cat threw up ) with the premise ( her dinner was old ). Let s take another proposition: All cats are grey. We can translate this statement into a conditional by adding if-then connectors: If it is a cat then it is grey. Notice that the two sentences mean the same thing. There are two parts to a conditional, an antecedent, and a consequent. The antecedent is the proposition of the if clause, and the consequent is the proposition of the then clause. You can think of the antecedent as the cause, and the consequent as the effect. The antecedent to the sentence above is it is a cat and the consequent is it is grey. Without the ability to do conditional reasoning, we could not, for example, create computer programs that rely on if-then instructions. We also would not be able to reason about the future. Consider when someone says, don t stick your fingers in the light socket, otherwise you d electrocute yourself. We can change this into a

6 conditional statement: If you stick your fingers in the light socket, you will be electrocuted. The conclusion is found in the consequent of the sentence ( you will be electrocuted ), and the reason/ premise is in the antecedent ( you stick your fingers in the light socket ). Voila. Conditional statements are important because they are like mini arguments. Although we won t talk about valid deductive arguments until next time, I want to point out one of the coolest things about logic. Assume for the moment that the conditional statement is true, that is that All cats are grey, or If it is a cat, then it is grey. If that argument is true, then IF the antecedent is true, then the consequent MUST be true. For example, say it is true that I have a cat. Then you know absolutely for certain that it is grey. Here is the argument outline: Premise: If it is a cat, then it is grey. (Conditional statement) Premise: I have a cat. (By empirical evidence) If these two premises are true, then what can we conclude? We MUST conclude that my cat is grey: Conclusion: My cat is grey. The conclusion is guaranteed to be true as long as the premises are true. Pretty cool, huh? Practice arguments. Take the following statements and find the premises and conclusion: It must have rained last night. My fridge is empty. The road is wet. If the road is wet, it rained last night. The proper outline is: P1. (premise): If the road is wet, then it rained last night. (conditional inference statement) P2: The road is wet. (empirical evidence). C (conclusion): It must have rained last night. The statement My fridge is empty is unnecessary and should not be included in your outline. We will practice many more arguments next time. Be sure to read Vaughn chapter 2, and Perry s logical toolkit many times if you don t understand something. Look on the internet for argument types and forms. ASSESSMENT: Under Handouts, I included a folder called Reasoning Tutorials. These files contain several additional primers for how to recognize and assess arguments. Read one of them and then write a one-paragraph summary. You will

7 write this summary for the logic exam. You only need to read one of these files, but you may want to read more to develop your critical thinking skills. (It s food for the mind as Russell says.) DISCUSSION QUESTIONS: Once you start noticing arguments, you will find them everywhere. List a few arguments that you come across, say, from your friends, commercials, radio, newspaper, etc. See if you can detect some good arguments from some bad ones. Perry (in the logic toolkit ) talks about PERSUASION as an indicator that an argument is good. That is, an argument succeeds if the person is able to persuade someone to believe it. Do you think persuasion is a good criteria for what counts as a good argument?