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B. Examining the Argumentʹs Logic

Bad arguments donʹt make sense. “Making sense” means that one point follows logically from another and that the conclusion follows from the premises. If Iʹm in Wisconsin and tell you, ʺI have to go to Chicago so Iʹm heading north,ʺ youʹll think Iʹm weird. The conclusion (head north) doesnʹt follow logically from the premise (go from Wisconsin to Chicago). Bad arguments fall into wellknown patterns called fallacies that are described on the next sheet, ʺCommon Errors of Logic in Argumentative Writing.ʺ

Sound or valid arguments, on the other hand, are reasonable; they follow the rules of logic. There are two main patterns of valid argument, deductive and inductive. In a ʺdeductiveʺ argument, the premises inevitably prove the conclusion; logically, they canʹt lead anywhere else and the conclusion needs no other support (like the Socrates example, above). In contrast, the premises of an ʺinductive” argument only suggest or point to a conclusion without proving it beyond all doubt; usually they rely on probability to help the reader infer ‐‐ make a logical leap to ‐‐ the conclusion. Example: ʺIʹm almost never late for school, so I wonʹt be late today.ʺ In fact, you might end up late even though you probably wonʹt; thereʹs no causal connection between the premise (almost never) and the conclusion (I wonʹt be late today). Instead, you have to make a leap of faith between the two.

Look at the argument that you outlined above and try to answer these questions about it:

1. Are the authorʹs premises clear? Are they true? Are they supported by any evidence?

  • 2..

    Does the conclusion follow logically from the premises?

  • 3.

    How many of the logical errors listed on the next sheet does the author



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