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Bob Muhlnickel Chris Tillman
Argument in the College (DRAFT)
The goal of CAS 105 is for you to learn to write successful argumentative essays. Argumentative essays, of course, consist of arguments. An argument, in this sense, is simply a set of statements, consisting of at least one argument-conclusion (hereafter, arg-conclusion ) and at least one premise. The two main ways that an argument can go wrong are if its premises fail to support its arg-conclusion, or if its premises are not all true. While there is unfortunately no systematic procedure for ensuring that your premises are all true, this manual outlines a strategy for constructing cogent arguments that helps you avoid the first problem. The following explains in detail, by appeal to an extended example, how to Present, Explain, and Evaluate (PEE) an argument, step-by- step. An argument that is correctly PEE-ed is vastly clearer than a typical prose argument. In addition, the premises of a correctly PEE-ed argument are guaranteed to support its conclusion. Finally, by using PEE, you will have the advantage of being able to state exactly where an argument goes wrong. As a result, being able to correctly PEE arguments puts you at a significant advantage, particularly when the subject matter of the argument(s) is complex, as is often the case in college writing. The manual is organized as follows: there is a section on Presenting Arguments, followed by a section on Explaining Arguments, and a section on Evaluating Arguments. In each section, there is a brief outline of what is involved in Presenting, Explaining, and Evaluating, respectively. Following that is a more detailed explanation of each
component as well as some extended examples to serve as illustration. Finally, we discuss some critical reading and writing skills and how PEE can help you develop them.
Presenting Arguments
To present an argument, do the following: (a) Locate the conclusion of the argument and formulate it in clear, literal terms. (b) Locate the central premises from which the conclusion is derived, and formulate them in clear, literal terms. (c) Formulate implicit premises so as to make the argument valid. (d) Write out the entire argument in numbered premise-conclusion form. Locate the conclusion of the argument and formulate it in clear, literal terms.
1. What is the conclusion of an argument? The arg-conclusion of an argument is a statement of the position being argued for or against. It is the main claim for which reasons are provided. It is distinct from an essay conclusion , which is typically the essay’s closing section that summarizes the essay and/or makes clear the essay’s contribution to its topic, and reinforces the essay’s thesis. It is also worth noting the relationship between an arg-conclusion and a thesis or a hypothesis. The arg-conclusion is often not the thesis of the essay. If you are PEE-ing an argument that you came up with, the arg-conclusion of that argument will typically be a one-sentence statement of your paper’s thesis. But the arg-conclusion of an argument is often not the thesis. If you are PEE-ing an argument from a text, your thesis will often be the denial of the arg-conclusion of that author’s argument. For example, if you were to
conclusions are supported by some premises he’s identified. Now that we know what an arg-conclusion is, we need some idea of how to find it. Here are some tips to help you identify the arg-conclusion: Arg-conclusion-finding tip 1:Look for arg-conclusion indicator terms If you are PEE-ing an argument from a text, you can often find the arg-conclusion by finding conclusion-indicator terms, which typically indicate that an arg-conclusion follows. Examples of arg-conclusion-indicator words are ‘therefore’, ‘hence’, ‘so’, and the phrase, ‘as a result’. Here is an argument for the arg-conclusion that abortion is immoral from Ernest Lepore: If a fetus is a person, then it has a right to life. If a fetus has a right to life, then abortion is immoral. So abortion is immoral. Note that the arg-conclusion of the argument Lepore presents begins with a conclusion- indicator term: “So abortion is immoral.” It is helpful to use conclusion-indicator terms in your essay to help the reader identify your arg-conclusion(s). Arg-conclusion-finding tip 2: Look for an explicit statement of the arg-conclusion The second strategy for locating an arg-conclusion involves quickly reviewing the work to find out if the author states the explicit conclusion of an argument. The author may explicitly state the conclusion of an interesting or challenging argument at any point in the work, although section beginnings and endings are places an author frequently
identifies the explicit conclusion of an argument. For example, here’s an argument from the appendix of Morton White, What is and What Ought to be Done , p. 125: 1 (1) Whoever takes the life of a human being does something that ought not to be done. (2) The mother took the life of a fetus in her womb. (3) Every living fetus in the womb of a human being is a human being. (4) The mother took the life of a human being. (5) The mother did something that ought not to be done. In White’s argument, the arg-conclusion is clearly and explicitly stated in the last line of his argument. Arg-conclusion-finding tip 3:Look for the most comprehensive idea As you skim the work or a section, look for the most comprehensive idea. The most comprehensive idea is likely to be the arg-conclusion that the entire essay or the section supports. An argument is often constructed to support a comprehensive idea using premises to support the comprehensive idea. Here are some questions to have in mind when working on identifying the arg-conclusion: “What’s the main point of this work or section?” “What is this author arguing for?” “What idea does everything else lead to?” Arg-conclusion-finding tip 4: Read and re-read (^1) A brief note about numbering may be in order. Rarely will you read a paper in which the argument is displayed using numbered sentences. However, it is useful to number the sentences in order to keep track of them when we are formulating our argument, even if the numbers do not appear in the final draft of your argumentative essay.
enough; it is counterproductive to cloud your argument with misleading, ambiguous, or otherwise confusing language. Locate the central premises from which the arg-conclusion is derived, and formulate them in clear, literal terms.
1. What is a premise? The premises from which the conclusion is derived are the reasons given in support of the conclusion; that is, the reasons for thinking that the arg-conclusion is true. If you are PEE-ing an argument you came up with, the premises should include the main reasons you would give in support of your arg-conclusion. They are what you might say to convince an interested and intelligent neutral party that the conclusion is correct. This should consist of some supporting points and some reasons to suppose that the conclusion must be correct, given those points. Similarly, if you are PEE-ing an argument from a text, the premises are the main reasons the author gives in support of the conclusion. They are often answers to the question, “Why think that’s true?” For example, suppose our arg-conclusion is that it is not the case that the fetus’s right to life always outweighs the pregnant woman’s right to decide what happens in her body. Why might one think that’s true? One might think that any case of rape grossly violates a woman’s rights, so having an abortion in cases of rape is not outweighed by the fetus’s right to life. We could state our argument as follows:
- Rape is a gross violation of a woman’s rights.
- Having an abortion in cases of rape is not outweighed by the fetus’s right to life.
- So, it’s not the case that the fetus’s right to life always outweighs the pregnant woman’s right to decide what happens in her body. Line ( 3 ) is our arg-conclusion, and (1) and ( 2 ) are the premises. Formulate the premises as succinct declarative sentences. Remember to avoid wordiness or confusing terminology. 2. How Are Premises Located? a. Critical Reading Skill: “Working Backward” The critical reading skill “working backward” is useful for identifying premises. Once you’ve identified the arg-conclusion, you need to identify the premises that support the arg-conclusion. Some premises will be in the work you’re reading, others will not. Therefore, a critical reading skill is “working backward” from the arg-conclusion to identify the premises for the arg-conclusion. While we read most fiction and most casual writing from beginning to end, this habit does not help analyze argumentative essays. In many disciplines, authors do not list premises in order as White does in the above example. Considerations of style, readership preference, and disciplinary conventions result in a polished essay that the reader must analyze carefully in order to identify the premises of an argument. After you’ve identified an arg-conclusion you may need to use other strategies to identify the premises. You may need to re-read the work several times, re-read some sections more than others, and re-read sections in an order besides that in which they are published in order to identify premises. Here are some tips for working backward. One, based on your previous reading, re-read sections you think are most relevant to the arg-conclusion you’ve identified. Two, look for section summaries, tables, graphs, lists, and formal arguments. These are places where authors often list important concepts related to the argument and its premises. Three, as you identify statements that could be premises, ask yourself: is this statement a
their field and, as a result, often do not explicitly state all of their premises. Writers investigating a topic with which they are unfamiliar may have difficulty identifying implicit premises. An instructor or reference librarian can often help you find sources of background information that experienced writers assume their readers possess. Here are some questions to have in mind when working on identifying premises: o What might support this arg-conclusion? o Are there combined statements or concepts in the arg-conclusion that are defended or explained individually in other parts of the work? o Does the author explicitly identify ‘evidence,’ ‘reasons,’ ‘support,’ or ‘warrants,’ in the text? (These terms also often indicate premises.) Finally, it is important to note that the premises may come before or after the conclusion. In the argument against abortion presented by Thomson, note that the premises precede the conclusion: Every person has a right to life. So the fetus has a right to life. No doubt the mother has a right to decide what shall happen in and to her body; everybody would grant that. But surely a person’s right to life is stronger and more stringent than the mother’s right to decide what happens in and to her body, and so outweighs it. By listing the premises and the arg-conclusion, we can Present a formal argument for the argument’s conclusion. Suppose we wish to extract an argument from Thomson for the arg-conclusion that abortion is immoral. The first premise from Thomson’s text could be (1) Everyone has a right to life.
The second premise could be: (2) So the fetus has a right to life. Recall that ‘so’ indicates an arg-conclusion. And (2) is one of the arg-conclusions we identified above. That’s OK; often, the arg-conclusion of one argument is a premise in another. In the argument we’re considering, ( 2 ) is part of the support for our main arg- conclusion, but it is in turn supported by (1). So in the argument we are constructing, (2) is a sub-conclusion. The third premise might be: (3) A person’s right to life is stronger and more stringent than the mother’s right to decide what happens in and to her body. A further sub-conclusion is: (4) So, a person’s right to life outweighs the mother’s right to decide what happens in and to her body. Finally, we might conclude: (5) Therefore, abortion is immoral.
premises, then it is unsound. It is important to be able to construct valid arguments, since the premises of a valid argument are guaranteed to support the conclusion. That is, a valid argument is an argument where the conclusion is guaranteed to be true, if the premises are true. Here’s a slogan: Truth of the premises guarantees truth of the conclusion. Another way to put the same idea is that if an argument is valid, it’s impossible for its premises to all be true, yet its conclusion false. It’s important for your argument to be valid. Sometimes an argument’s premises fail to support its conclusion. That’s bad. So we want to make sure that none of our arguments turn out this way. When we evaluate the arguments of others, we want to be charitable and formulate their arguments in a way that makes them valid. In addition, facility with formulating valid arguments increases your options as a writer. Often, authors leave implicit premises unstated and undefended. In constructing a valid argument, we identify implicit premises. In explaining the argument, we give support for each premise. It is often the case that, in the course of PEE-ing an argument, one discovers that, in order for the argument to be valid, weak implicit premises must be included. These weaknesses may be glossed over in the passage from which the argument is PEE-ed. But PEE-ing the argument exposes these weaknesses, providing authors with more options for resisting a premise in the argument. Digression: Inductive Arguments What is it for premises to support a conclusion? That’s a very hard question to answer adequately. There are invalid arguments where the premises support the conclusion. In fact, most of us usually encounter invalid arguments where the premises
support the conclusion in some way or other. Many of these arguments are inductive arguments. Consider the following:
- Tweety is a bird.
- Therefore, Tweety flies. The truth of (4) surely gives us a good reason to think that (5) is true. So ( 4 ) supports (5), though ( 4 - 5 ) is clearly invalid, as are all inductive arguments. The truth of ( 4 ) does not guarantee the truth of ( 5 ). After all, Tweety could be a penguin, Tweety could be a chick that’s not old enough to fly, Tweety could be dead, and so on. Here’s another (inductive) argument that gives support for the conclusion yet is not valid:
- The last 10 , 000 swans I’ve seen have been white.
- Therefore, if I see another swan, it will be white. It turns out that there are black swans in Australia. But even if there weren’t, this argument would not be valid because it would still be possible for there to be non-white (visible) swans, and that would be enough to make the argument invalid. Remember: if the argument’s valid, it’s not even possible for the premises to be true but the conclusion false. If an argument is deductively valid, truth of the premises guarantees truth of the conclusion. Fortunately, there is a procedure for turning any inductive argument into a valid argument. The most straightforward way to do this is to weaken the arg-conclusion. Here are reformulations of ( 4 - 5) and ( 6 - 7 ) as valid arguments:
section to render the argument valid. In so doing, you will uncover the implicit premises in the argument, if any. The result is a correctly presented valid argument. So recall that an argument is valid if the truth of the premises guarantees the truth of the conclusion. But how do we know when the truth of the premises guarantees the truth of the conclusion? Some arguments are valid merely in virtue of their form. The form of an argument is the way in which its meaningful parts are “put together.” Consider the following argument:
- Some swans are white.
- Some pigs are fat.
- Therefore, some swans are white and some pigs are fat. It is impossible for it to be the case that (23) and ( 2 4) are true, yet ( 25 ) is false, so ( 23 - 25) is valid. We can abstract away from the specific sentences used in ( 23 - 25) to make explicit the valid argument form. Consider ( 26 - 28 ):
- Blahblah.
- Bleeblee.
- Therefore, Blahblah AND Bleeblee. If we replace ‘blahblah’ and ‘bleeblee’ with any sentences whatsoever, we form a valid argument. In ( 26 - 28 ), ‘blahblah’ and ‘bleeblee’ are place-holders for sentences. We sound less silly if we use capital letters instead of nonsense expressions. But which expressions should we abbreviate with capital letters? In order to find out, we need to distinguish between simple and compound statements.
A statement S is simple if, and only if, it does not contain any logical connectives. A statement S is compound if, and only if, it is not simple. Logical connectives are expressions that are used to build logically complex statements out of simpler statements. For example, the occurrence of ‘and’ in (25) functions to conjoin the simpler statements (23) and (24). The main logical connectives we will be concerned with are: Conjunction : ‘and’, ‘but’, ‘while’, ‘even though’, ‘yet’, ‘nevertheless’, ‘;’ 2 Negation : ‘not’, ‘it is not the case that’, ‘it’s false that’, ‘un-’, ‘im-’, some uses of ‘no’ Disjunction : ‘either …, or’, ‘or’ Conditional : If … , then … In order to correctly represent the logical form of an argument, we adopt the following rule: (^2) ‘And’ may be used between statements to form a logical conjunction, as in: Bob was breakdancing and Chris was breakdancing. ‘And’ may also be used to conjoin sub-sentential expressions, like main verbs, auxiliary verbs, adverbs, objects, or subjects, as in: Bob killed and ate the innocent furry bunny. Bob was and will be breakdancing. Chris breakdances quickly and quietly. Bob ate hash and Twinkies. Bob and Chris fought the bad guys. Similar points hold for ‘or’, though ‘or’ may, in addition, be used to disjoin adjectives, as in: I have either the meanest or the ugliest instructor.
It is very important to note that we can substitute in any sentences whatsoever for ‘P’ and ‘Q’, whether or not they are true, and we still get a valid argument. Consider ( 32 - 34 ):
- Pigs can fly.
- The moon is made of green cheese.
- Therefore, pigs can fly and the moon is made of green cheese. Notice that ( 32 - 34) is valid. Were the premises true, the conclusion would have to be true as well. A rough-and-ready (though imperfect) test is this: imagine a situation in which the premises are true. Is the conclusion true in that situation? Does it have to be? When we imagine that, contrary to fact, pigs fly and the moon is made of green cheese, we are imagining a situation in which the premises of ( 32 - 34) are true. But that must also be a situation in which the conclusion is true. So the argument is valid. It is very easy to see that a very simple argument form, like ( 32 - 34), is valid once we present the argument in a way that makes its form explicit. It is not as easy with some other argument forms. Fortunately, most arguments in texts or that we think up do not have very complicated forms, or need not have very complicated forms. If we familiarize ourselves with a few common valid forms, we have all we need to extract and present valid arguments. The following are seven very common argument forms: Modus Ponens (MP) Modus Tollens (MT) (1MP) If !, then ". (1MT) If !, then ". (2MP)! (2MT) Not-". (3MP) Therefore, " (3MT) Therefore, Not-!. Hypothetical Syllogism (HS) Reductio ad Absurdum (R)
(1HS) If !, then ". (1R) Assume !. (2HS) If ", then #.... (3HS) Therefore, if !, then #. ( n R) " and Not-". (Alternatively: if ", then Not-", and if Not-", then ".) ( n +1R) Therefore, Not-!. Disjunctive Syllogism (DS) Dilemma (D) (1DS)! or ". (1D)! or ". (2DS) It’s not the case that !. (2D) If !, then #. (3DS) Therefore, ". (3D) It’s not the case that #. (4D) Therefore, ". And, as we saw above, Conjunction (C) (1C)! (2C) " (3C) Therefore,! and ". Any argument that has one of these forms is valid. That is, the truth of the premises guarantees the truth of the conclusion. Digression: Use of Greek Letters We use Greek letters to specify the argument forms instead of capital letters, since we chose capital letters to abbreviate only simple statements. The Greek letters may be replaced by either simple or compound statements. For example, the following argument is an instance of Modus Ponens:
