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Example 5
 
Introduction to Philosophy
(Metaphysics and Epistemology)
Premise-Conclusion Form
When you write a philosophy paper (or any other paper, for that matter), you will be doing one of two things:  reconstructing and evaluating the argument of some other author, or constructing an argument of your own.  Either way, it is important to have a feel for the various ways in which arguments can be put together, and the best way to acquire this "feel" is to practice translating arguments into premise-conclusion forms.
An argument is just a string of sentences (or claims, or assertions), but there are two types of sentences in an argument:  the premises and a conclusion.  The conclusion might be a claim or assertion that you want another person to accept, or it might be something that you yourself believe, but which has been challenged by another person.  The premises, on the other hand, are sentences from which the conclusion can be inferred, or reasons for believing the conclusion.

The following argument is in premise-conclusion form:

(1) No dinosaur species survived the ecological catastrophe 65 million years ago.
(2) Tyrannosaurus rex is a dinosaur species.
(3) Tyrannosaurus rex did not survive the ecological catastrophe 65 million years ago.

First, notice that all the lines in this argument are numbered.  This just makes it easier to talk about the argument.  You can say, for example:  "This argument fails because premise (1) is false."  Notice also that every line is a complete sentence.  Every line of the argument must be a freestanding assertion, something you can believe or not believe, something that could be true or false.
When you put an argument into premise-conclusion form, the last line is always the conclusion, and it is often helpful to single out the conclusion with the help of the little sign ". .," which means "therefore."  It is also common practice to underline the last premise.  (This just helps you see the difference between the premises and the conclusion.)  The notation that you use for premise-conclusion form is the same as the notation you use when constructing proofs in geometry, where the point is also to see the relationship between premises and conclusion.  Another thing to remember is that an argument can have any number of premises.  Some arguments only have one premise.  The following is an example that we will run into later on this semester.

(1) I think.
(2) I exist.

There are, in general, two different kinds of arguments: arguments about what to do (philosophers call these "practical arguments) and arguments about what to believe (or "theoretical arguments).  These different kinds of arguments have different kinds of conclusions.  The conclusion of an argument about what to do is always an instruction or imperative of some kind, whereas the conclusion of an argument about what to believe is an assertion or declarative sentence.  Ethics is the branch of philosophy concerned with arguments about what to do, while logic and epistemology are the branches concerned with arguments about what to believe.

How Do Arguments Figure Into Philosophy Papers?
Two skills are absolutely crucial for writing philosophy papers (or any other papers, for that matter).  The first is the ability to construct your own argument about what to believe; the second is the ability to reconstruct someone else's argument.  Actually, you might think of these as a single skill.  The only real difference between them is whose conclusion we are talking about -- your own or someone else's.
Constructing Your Own Argument
When you sit down to write a paper, Weston's Rulebook for Arguments should be by your side.  Chapters VII, VIII and IX should be especially helpful when it comes to constructing your own arguments, and my advice is to read these chapters before you begin to write.  Here are a couple of tips in addition to what Weston says.

(1) Begin with your conclusion.  If your paper is going to be an argument about what to believe, it is absolutely necessary to tell the reader what to believe.  Formulate your conclusion or thesis even before you begin to write.  Think about it this way:  if you were to put your argument into premise-conclusion form, you would have to have a single assertion on the last line.  What assertion will you put there?  As a rule (though there may be exceptions) you should be able to state your thesis or conclusion in a single sentence.

There is nothing wrong with changing your mind about your conclusion as you write the paper, this happens all the time.  But remember that if you alter your conclusion at any point, you need to go back and revise the earlier parts of your paper in order to make everything fit together as a single argument.

Here is one more thing to keep in mind when thinking about your thesis:  never try to defend a conclusion that is either trivially true or obviously false.

(2) Then fill out your argument.  The next step is to develop an argument in support of your conclusion.  Here again, it may help to begin by sketching an argument for your thesis in premise-conclusion form.  You can then use the premise-conclusion form as an outline.  (One easy way to do this would be to include a paragraph or two in your paper for each premise in your argument.  The job of these paragraphs would be to explain and support each premise.  But there are other ways too.  Be creative).  The advantage of this approach is that if you use the premise-conclusion form as a rough guide to writing your paper, you can be pretty sure at the end that your paper as a whole embodies an argument about what to believe.
Reconstructing Someone Else's Argument
This is one of the things that professional philosophers do for a living and in several of your paper assignments this semester, you will be asked to reconstruct the arguments of philosophers like Descartes and hume.  (In fact, the best way to learn how to construct knock-down arguments of your own is to begin by reconstructing those which turned out to be knock-down arguments in the past.)  In philosophy, the difference between primary literature and secondary literature is the difference between a philosopher's original construction of some argument (this is the primary literature) and some later philosopher's reconstruction of and commentary on the same argument (this is the secondary literature).  Here again, I hope that Weston's Rulebook will be helpful to you, but I also have a couple of further tips:
(1) Begin by looking for the author's conclusion.  In some cases, this will be obvious.  For example, the conclusion of all the arguments for the existence of God is just that God exists.  In cases where the conclusion is not obvious, it helps to look for key words and phrases like "therefore," "it follows that, " "hence," or "we can infer that."  Or just ask yourself what the author wants you to believe.
(2) Then fill out the author's argument.  Here again, the easiest way to proceed is to begin by putting the author's argument in to premise-conclusion form.  This will help you to see the whole argument at a glance, and it will provide you with a rough outline for (at least) part of your paper.  Again, you might devote a paragraph or two to explaining each of the author's premises.  Why should anyone accept these premises?  Does the author provide any reasons for accepting them?  How do they support the conclusion?
One rule that you must follow when reconstructing someone else's argument is the principle of charity.  This is extremely important.  According to the principle of charity, you should treat the other person's argument--the one that you are trying to reconstruct--as if it were an argument that you yourself had constructed.  When constructing an argument of your own, you naturally try to make it as compelling as possible, so even if you eventually plan to criticize or refute the argument you are reconstructing, try to reconstruct it in such a way as to make it seem as compelling as possible.
Evaluating Someone Else's Argument
Some of your assignments will ask you to evaluate or criticize a philosopher's argument.  The point of this sort of evaluation is just to explain whether an argument is good or bad.  The chapter on fallacies in Weston's Rulebook should be helpful here, as well as the piece by Carl Sagan in the class pack.  It is extremely important to remember, however, that everything yo do at this stage depends upon how well you have reconstructed the other author's argument.  Everything here depends upon how well you have "set up" the argument you are trying to evaluate.