Evaluating Arguments & Truth Claims

Introduction
Evaluating arguments
When is an argument a good one?
When is it reasonable to accept premises?
Refuting arguments

1. Evaluating Arguments & Truth Claims PRESENTED TO: MA’AM RABIA 

2. Presentation Plan Introduction Evaluating arguments When an argument a good one? When is it reasonable to accept a premises? Refuting arguments 2

3. INTRODUCTION What is an argument? Arguments are composed of one or more premises and a conclusion.  Premises  are statements in an argument offered as evidence or reasons what we should accept another statement, the conclusion.   The  conclusion  is the statement in an argument that the premises are intended to prove or support.  An  argument,  accordingly, is a group of statements, one or more of which (called the premises) are intended to prove or support another statement (called the conclusion). 3

4. INTRODUCTION (CONT.) The three goals of critical argumentation are to identify, analyze, and evaluate arguments.  Primarily, argument has two purposes:  Argument is used to change people's points of view or persuade them to accept new points of view;  And argument is used to persuade people to a particular action or new behavior. Argument teaches us how to evaluate conflicting claims and judge evidence and methods of investigation. It also helps us learn to clarify our thoughts and articulate them honestly and accurately and to consider the ideas of others in a respectful and critical manner. 4

5. EXAMPLE Claim: Smoking cigarettes is injurious to health. Support:  Tobacco kills over 163,600 people each year in Pakistan. Almost 31,000 of these deaths are due to exposure to secondhand smoke. Tobacco causes about 16.0% of all male deaths and 4.9% of female deaths. Overall, 10.9% of all deaths are caused by tobacco. Tobacco causes 66.5% of all deaths from tracheal, bronchus, and lung cancer, 53.2% of deaths from chronic obstructive pulmonary disease, 21.9% of deaths from ischemic heart disease, 15.2% of deaths from diabetes mellitus, and 16.8% of deaths from stroke. 5

6. EXAMPLE Claim: Junk food is bad for your health. Support: Eating too much junk food is linked to serious health problems. Eating junk food on a regular basis can lead to an increased risk of obesity and chronic diseases like cardiovascular disease, type 2 diabetes, non-alcoholic fatty liver disease and some cancers. It can affect the brain function and slow down the ability of learning new skills. 6

7. TRUTH CLAIMS 7 In order to be in a position to judge whether a given statement is true or false it is first necessary to have a notion of what it means for a statement to be true.  This is to say that in order to properly assess truth claims we must have at least a working account of what truth is.  Although we generally get by with intuitive notions of truth, for the critical assessment of arguments we really need a more precise account. In religion, a truth claim is an assertion that the belief system holds to be true; however, from the existence of an assertion that the belief system holds to be true, it does not follow that the assertion is true. For example, a truth claim in Judaism is that only one God exists. Conflicting truth claims between different religions can be a cause of religious conflict.

8. TYPES OF TRUTH CLAIMS All statements can be regarded as making a truth-claim. Truth-claims that can be shown to be true are verified and those shown to be false are falsified.   Empirical truth claims The sentence The Oxford English Dictionary has a definition of ‘definition’ can be verified by looking in the dictionary to see whether the OED has the appropriate entry. Certain claims, such as claims about the past or future cannot be supported by direct evidence and so can only be supported indirectly. Statistical empirical statements make a claim about some proportion of a class of objects or events, such as: 90% of snapping turtles do not survive the first three months of life. Universal empirical statements make a claim about all objects or events of some kind, such as: All ravens are black. 8

9. TYPES OF TRUTH CLAIMS (CONT.) Non-empirical truth claims Statements that fall under this category cannot, in principle, be verified on the basis of empirical evidence. Statements that fall in this category are moral, aesthetic, religious and mathematical.  In ethics, such principles are moral principles—they enable one to determine the truth of any moral claim.  In religion these principles are principles that must be accepted on faith.  In mathematics these principles are axioms that are, usually, taken to be self-evident.  9

10. Evaluating arguments Definition:  To evaluate means to judge or assess. Purpose : It is important for a reader to be able to process information given and decide if the information is factual, leading or biased in order to form an opinion. Evaluate Types of Evidence •  Is it sufficient to support the claim? •  Is the evidence relevant to the claim? •  Can the evidence be proven as fact, not opinion? Is there bias? •  Personal experiences may be biased •  Watch for leading language ✓ Words that have strong positive or negative connotations like “wise” or “terrible”. •  Did the author omit (leave out) important information?

11. Evaluating arguments (cont.) Opposing Viewpoints or Counter-argument •  Does the author address opposing viewpoints clearly and fairly? •  Does the author refute the opposing viewpoint with logic and relevant evidence? Advertising or Propaganda Techniques •  Bandwagon technique: “Everyone is doing it! You should too!” •  Plain Folk: the “average” person uses this or a politician can relate to the typical American  •  Celebrity or Doctor Endorsement: Adam Levine for Proactive .

12. Strategies for evaluating an argument • Identify the claim. • Outline the reasons to support the claim. • What types of evidence are used? • Evaluate the evidence. Is their enough evidence provided and does it make sense? • What emotional appeals are used? • Is there language with strong positive or negative connotations? 12

13. When an argument is a good one? 13 Arguments can be good or bad in various ways. To help us understand what a good argument is from the standpoint of critical thinking, we begin by spelling out a few things that a good argument is not. What “Good Argument” Does Not Mean: “Good Argument” Does Not Mean “Agrees with My Views” “Good Argument” Does Not Mean “Persuasive Argument” Persuasive Argument : An argument that actually succeeds in convincing an audience to accept a conclusion. •  Does this hold true of arguments as well?  •  Is a good argument a persuasive argument? •  Its not necessarily and for two reasons. “Good Argument” Does Not Mean “Well-Written or Well-Spoken Argument”

14. When an argument is a good one ? What “Good Argument” Does Mean: A good argument is basically an argument in which two conditions are met:  All the premises are true The premises provide good reasons to accept the conclusion. A set of premises provides good reasons to accept a conclusion when the argument is either deductively valid or inductively strong.  Deductively Valid:  An argument is deductively valid if the conclusion must be true if the premises are true. Inductively strong:  An argument is inductively strong if the conclusion is probably true if the premises are true. A good argument, from the standpoint of critical thinking, is an argument that satisfies the relevant critical thinking standards that apply in a particular context. The most important of these standards are  accuracy  (Are all the premises true?) and  logical correctness  (Is the reasoning correct? Is the argument deductively valid or inductively strong?). 14

15. Evaluating Arguments:  Some General Guidelines    Given the general definition of “good argument,” we can offer the following general guidelines on evaluating arguments. •  Are the premises true?  •  Is the reasoning correct? Is the argument deductively valid or inductively strong?  •  Does the arguer commit any logical fallacies?  •  Does the arguer express his or her points clearly and precisely?  •  Are the premises relevant to the conclusion?  •  Are the arguer’s claims logically consistent? Do any of the arguer’s claims contradict other claims made in the argument?  •  Is the argument complete? Is all relevant evidence taken into account (given understandable limitations of time, space, context, and so on)?  •  Is the argument fair? Is the arguer fair in his or her presentation of the evidence and treatment of opposing arguments and views? 15

16. When is it reasonable to accept a premises? All good arguments, as we have seen, have true premises. But when is it reasonable to accept a premise as true?  Let’s suppose that somebody asserts a claim—for example, that women are more superstitious than men or that I saw Elvis at a Dunkin’ Donuts in Lubbock. For simplicity, let’s suppose that the claim is unsupported (i.e., no argument is given for it) and that for some reason it is either impossible or not worthwhile to try to verify the claim for ourselves. Under what conditions is it reasonable to accept such a claim?  The most general principle can be summed up in the following principle of rational acceptance: generally speaking, it is reasonable to accept a claim  If the claim does not conflict with personal experiences that we have no good reason to doubt The claim does not conflict with background beliefs that we have no good reason to doubt The claim comes from a credible source. 16

17. When is it reasonable to accept a premises? Does the claim conflict with our personal experiences? Sometimes people claims that conflict with our own personal observations and experiences. When this happens it is usually best to trust our own experiences.   Critical thinkers also recognize that their beliefs, hopes, fears, expectations, and biases can affect their observations. Children, for example, “see” monsters in the closet. Sports fans perceive referees as partial to the other team.   In short, personal experiences are often less reliable than we think. We need to be aware that often “believing is seeing” and that things are not always as they appear.   

18. When is it reasonable to accept a premises? Does the Claim Conflict with Our Background Beliefs? Sometimes a claim doesn’t conflict with any of our personal observations or experiences but does conflict with certain background beliefs we hold.   By “background beliefs” we mean that vast network of conscious and unconscious convictions we use as a framework to assess the credibility of claims that can’t be verified directly. In general, if a claim fits well with our background beliefs, it is reasonable for us to accept it.   For example, the claim, “It was hot in Las Vegas last fourth of July,” is quite believable given background information most of us share about midsummer weather conditions in the Nevada desert. The claim,   “It snowed in Las Vegas last Fourth of July,” however, would rightly be rejected out of hand unless it was accompanied by strong supporting evidence.   The problem is that most of us place too much confidence in the accuracy of our background beliefs. A chain is only as strong as its weakest link.  

19. When is it reasonable to accept a premises? Does the Claim Come from a Credible Source? Much of what we believe about the world is based on testimony or authority. All of us believe, For example, that George Washington was the first president of the United States, that the earth revolves around the sun, that there is such a place as t he Sahara Desert, and that it is cold at the North Pole in January. Yet few of us have personally verified any of this information for ourselves.   Thus, a crucial Question for critical thinkers is When is it reasonable or justifiable to accept a claim based simply on the testimony or authority of another?

20. When is it reasonable to accept a premises? Good reasons to doubt the credibility of a source may include the following: The source is not a genuine expert or authority.   The source is speaking outside his or her area of expertise.   The source is biased or has some other motive to lie or mislead.   The accuracy of the source’s personal observations or experiences is questionable.   The source is contained in a source (e.g., a supermarket tabloid or sensationalistic Web site) that is generally unreliable.   The source has not been cited correctly or has been quoted out of context.   The issue is one that cannot be settled by expert opinion.   The claim made by the source is highly improbable on its face.  

21. Refuting argument To refute an argument isn’t merely to challenge, rebut, or criticize it. It is to defeat it, to show that the premises do not provide convincing reasons to accept the conclusion. Arguments can be criticized in various ways (e.g., as obscure, wordy, or repetitious). But there are only two ways in which an argument can be refuted: Show that a premise—or a critical group of premises—is false or dubious. Show that the conclusion does not follow from the premises. 21

22. 22 Strategy 1 Sometimes it is possible to defeat an argument by showing that a single premise is false.  Consider this example: All presidents live in the White House. Paris Hilton is president.  So, Paris Hilton lives in the White House.  Some arguments, however, cannot be refuted simply by showing that one  of their premises is false. Here is an example: Example : Children who have unsupervised access to the Internet may be exposed to pornographic and violent images.  Some sexual predators use the Internet to find and communicate with children.  Children have no ability to use a keyboard or mouse correctly. So, children should not be allowed unsupervised access to the Internet. 

23. 23 Strategy 2 The second way to refute an argument is by showing that the reasoning is faulty—that the conclusion does not follow properly from the premises. Here are two examples:  Get high-speed Internet access by satellite. It’s fast, reliable, and won’t tie up your phone lines.  All mothers should stay home with their young kids. It would promote closer family ties, and studies show that children with stay-at-home moms do better in school, have higher self-esteem, and are less likely to get involved with drugs or commit crimes.  In evaluating arguments of this sort, the important question to keep in mind is:  Do the premises provide enough evidence for the conclusion? 

24. THANKYOU! 24