RECGNIZING ARGUMENTS. in logical reasoning pptx
- 2. How do we recognize arguments? • In order to be an argument, a passage must set out to prove something. • Requirement for proving something • At least one statement must claim to present evidence or reason. • There must be a claim that something follows from the evidence, that the evidence implies something. • Essentially an argument must have at least one statement that acts as premise and there must be a claim that implies a conclusion.
- 3. Continue…… • The evidence doesn’t have to be real, truthful, nor do the premises need to support the conclusion, but the claim itself must be present. • These factors influence whether an argument is good or bad, but they change the fact that it is an argument. statement + claim = argument (premises) (conclusion)
- 4. Factual Claim • Factual claims are those expressed by the first condition. • Claims that can be proven with data, observation, and reliable sources Example • “ A huge rock from space struck the golf coast 65 millions years ago. You can prove this claim by studying the geology of the region.
- 5. Inferential Claim • Our focus will mainly deal with inferential claims, which are reflected by the second condition. They claim that a passage expresses a certain reasoning process: • One thing implies support to another, or that something follows from something. • Inferential claims can be either “ explicit or implicit” Argument make a FACTUAL claim (that the premises are true) and an INFERETIAL claims (that premises support the conclusion).
- 6. Types of inferential claims • Explicit inferential claims • An explicit inferential claims is relationship between statements that is recognizable by the use of premise or conclusion indicators (thus, because, for, therefore and so on) Example “Mad cows disease is spread by feeding parts of infected animals to cows, and this practice has yet to be completely eradicated. Thus mad cows disease continues to pose a threat to people who eat beef.”
- 7. Continue…… • Implicit inferential claims • There must be an implied relationship between statements in a passage, though there are no indicators words are used. Examples “ The genetic modification of food is risky business. Genetic engineering can reduce unintended changes into the DNA of the food-producing organism, and these changes can be toxic to the consumer.”
- 8. Caution when referring to indicator words • Be aware that sometimes indicators words do not guarantee an argument, if they are used in different way. Examples “Since Edison invented the phonograph, there have been many technological developments.” “ Since Edison invented the phonograph, he deserves credit for major technological development.” The word “since” on the top is used in reference to how much time has passed. Thus the first passage is not an argument. The “since” in the second passage is used in logical sense so the passage is an argument.
- 9. Non-inferential passage (non-arguments) • these are passages in which there is no claim that something is proved. • Such passages contain statements that could be premises or conclusions (or both), but what is missing is claim that any potential premise supports a conclusion or that any potential conclusion is supported by premises.
- 10. Passages of this sort include • Warning • Piece of advice • Statement of belief (opinion) • Loosely associated statements • Reports • Expository passages • Illustration • Explanation • Conditional statement
- 11. Warning • A form of expression that is intended to put someone on guard against a dangerous or detrimental situation Example • If you eat too much then you will get a stomachache. • It’s raining out so you will get wet of you leave. No evidence is given to support these statement so there’s no atgument
- 12. Piece of advice • Form of expression that makes a recommending about future decisions or behavior Example “ When you go to a job interview, be sure to dress neatly and be on time. Be sure to shake your employer’s hand and look him square in the eye. Try to show him you’re interested and really want job.” Again here, there is no evidence trying to prove something, so there’s no atrgument.
- 13. Statement of belief (opinion) • The expression about what someone believes or think about something Example “I think that going life with negative attitude is a waste of time. I’d prefer to look at things with a fresher perspective.” The author is making claim here but offers no evidence to support them, so they don’t qualify as argument.
- 14. Loosely associated statement • Statements that may be about a similar subject but they lack claim that one is proved by the other. Example “ You should always stand when a lady enters the room. Never burp at the dinner table. Chew with your mouth closed.” The statements all have to do with dinner etiquettes but they don’t offer any support for on another, so they are not arguments.
- 15. Reports • Group of statements that convey information about some topic or event. Examples “Even though more of the world is immunized than ever before, many old disease have proven quite resilient in the face of changing population and environmental conditions, especially in the developing world. New disease, such as AIDS, have taken their toll in both the North and South.” These statements could act as premises but they make no claims in support of something else, so they don’t qualify as arguments.
- 16. Expository Passages • Begins with a topic and is followed by one or more sentences that build upon the first one. Example “ There are three familiar states of matter: solid, liquid, and gas. Solid objects ordinarily maintain their shape and volume regardless of their location. A liquid occupies a definite volume, but assumes the shape of the occupied portion of its container. A gas maintains neither shape nor volume. It expands to fill completely whatever container it is in.” The first sentence introduces the passages and the rest of the paragraph expands on that sentence, but it doesn’t try to justify anything, so there’s no arguments.
- 17. Illustrations • Statements which refer to something else in order to explain something to show how it’s done. Example “ Recipes, instruction manuals, etc” They may use indicator words but they don’t actually try to prove anything, so they are not arguments.
- 18. Continue… • Some illustrations are taken as arguments: these are called Argument from example. • These arguments illustrate a process but do it to prove a point. Example “ Although most forms of cancer, if untreated, can cause death, not all cancers are life threatening. For example Basal cell carcinoma, the most common of all skin cancers, can produce disfigurement, but of almost never results in death.” The passage illustrates the effects of skin cancer, but the point of explanation is to show that not all cancers are life-threatening so they work as arguments.
- 19. Explanation • Group of statements that try to shed light on an event or an occurrence. These occurrence are usually thins that are commonly accepted. Example “ The sky appears blue from the earth’s surface because the light rays from the sun are scattered by the particles in the atmosphere.” “ Cows can digest grass, while humans cannot, because their digestive system contain enzymes not found in humans.
- 20. Parts of Explanation Explanandum The statement that describes the event or occurrences Explanans Statement or group of statements that do explaining.
- 21. Continue…. • The sky appears blue from the earth’s surface because the light rays from the sun are scattered by particles in the atmosphere. • Cows can digest grass, while humans cannot, because their digestive system contain enzymes not found in humans. The Explanandum for these two examples are bolded, and the explanans are underline.
- 22. Conditional Statements • A conditional statement is an “ if….. Then…..” statement. Example “ If Sarah Palin loves shooting wolves from airplanes, then she has little respect for wildlife.”
- 23. Parts of Conditional Statements • Antecedent The part after “if” but before “ then” • Consequent The part after “then”. If (antecedent), then (consequent). Or sometimes it is seen as: (consequent) if (antecedent) and the word “then” is left out entirely. Example “ I will stop bugging you if you’ll go out with me tonight.”
- 24. Continue….. • Conditional statements only say that if the antecedent is true, then the consequent has to be true. On their own, they don’t make up arguments since there is no claim in them that says they are true. Conditional statements only say that if one is true then other is also true.