©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Go To Next Slide 7-1 Diagramming Arguments The aim of this tutorial is to hone your skills in diagramming arguments.

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Diagram this argument. Step 1. Number each statement and note each indicator word. Since (1) Mary visited a realtor and (2) her bank’s mortgage department, (3) she must be planning on buying a home. Since Mary visited a realtor and her bank’s mortgage department, she must be planning on buying a home. Go To Next Slide

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Since (1) Mary visited a realtor and (2) her bank’s mortgage department, (3) she must be planning on buying a home. Step 2. Which of the claims is the conclusion? Which are premises? (1)(2)(3) Premise Note the indicator word, “since.” PremiseConclusion Go To Next Slide 7-2

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Since (1) Mary visited a realtor and (2) her bank’s mortgage department, (3) she must be planning on buying a home. Step 3. Use arrows to represent the intended relationship between the claims. (1)(2) (3) In this case the premises are independent. Even though the combined force of both premises makes the argument stronger, either premise could stand alone in supporting the conclusion. Go to next slide for another example 7-3

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Argument Diagramming Sample #2 Sandra can’t register for her classes on Wednesday. After all, Sandra is a sophomore and sophomore registration begins on Thursday. Step #1. Identify each claim and note any indicator words that might help identify premise(s) and conclusion(s). (1) Sandra can’t register for her classes on Wednesday. After all, (2) Sandra is a sophomore and (3) sophomore registration begins on Thursday. Go To Next Slide 7-4

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. (1) Sandra can’t register for her classes on Wednesday. After all, (2) Sandra is a sophomore and (3) sophomore registration begins on Thursday. “After all” is generally a premise indicator. This “and” serves to join two different claims. Go To Next Slide 7-5

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Step #2. Use arrows to show the relationships between the claims in the argument. (2)(3) (1) (2)(3) (1) (+) Decide whether the premises are independent. Or dependent. These are dependent premises since both (in conjunction) are necessary to prove the conclusion. Go to next slide for another example. 7-6

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Pool maintenance can cost hundreds of dollars a year and we really don’t have that kind of money. So, I don’t think we should put a pool in this summer. Besides, pools pose a real drowning danger to small children. Step #1. The first task is to analyze the argument. Decide what the various claims are and begin to decide which are premises and which are conclusions. Number the claims and note any indicator words. Go To Next Slide 7-7

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. (1) Pool maintenance can cost hundreds of dollars a year and (2) we really don’t have that kind of money. So, (3) I don’t think we should put a pool in this summer. Besides, (4) pools pose a real drowning danger to small children. Note the “and” connecting two claims. “So” is a conclusion indicator. A premise indicator. Go To Next Slide 7-8

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Step #2. Use arrows to represent the argument. (1)(2) (3) (+) Premises 1 and 2 are dependent. While premise 1 could stand alone, premise 2 can’t. (4) Premise 4 is independent. It could be offered alone as support for the conclusion. Go To Next Slide 7-9

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. (1) Pool maintenance can cost hundreds of dollars a year and (2) we really don’t have that kind of money. So, (3) I don’t think we should put a pool in this summer. Besides, (4) pools pose a real drowning danger to small children. (5) We don’t want dangerous things in the yard. (1)(2) (3) (+) (4) Notice that there is an implied premise here working in conjunction with #4. Do you see it? (+) (5) Go to next slide for another example. 7-10

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. You’ve often complained that mainstream television doesn’t have quality programming so I think you should support public broadcasting. Besides, you watch PBS all the time and fair is fair. Since support means money, you should write a check to PBS immediately. Step #1. As before, concentrate on analyzing the various claims. Use numbers to identify them and note any indicator words. Go To Next Slide 7-11

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. Go To Next Slide This argument is more complex, but the same skills apply. What is the intended conclusion of the argument? How do the various parts of the argument work to provide support for this conclusion? (1)You’ve often complained that mainstream television doesn’t have quality programming so (2) I think you should support public broadcasting. Besides (3), you watch PBS all the time and (4) fair is fair. Since (5) support means money, (6) you should write a check to PBS immediately. 7-12

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. You can start diagramming from anywhere. Keep trying different arrangements until your diagram best represents the intended meaning of the argument. (1) (2) The indicator “so” shows claim 2 to be a conclusion and 1 seems to support this conclusion. Claims 3 and 4 offer another reason that 2 is true. (3) (+) (4) Go To Next Slide 7-13

©2007 by The McGraw-Hill Companies, Inc. All rights reserved. What about claims 5 and 6? The “since” before 5 marks this as a premise but for which conclusion? Context and experience tell us that this is a premise supporting claim 6. Claim 2, which says you should support PBS, combines with claim 5 which defines support as money, to support the final conclusion 6. (1) (2) (3) (+) (4) (5) (6) (+) This is the end of the tutorial. 7-14