He Who Makes the Argument Determines the Scope

A common reason some otherwise attractive answer choices on the LSAT are incorrect is that they go beyond the scope of the argument.  Recognizing when answer choices are beyond the scope can take some getting used to, but the trick is to remember that the scope is determined by the person making the argument.  If someone attacks the argument with an objection that goes outside that scope, that objection is not valid.

For instance, let’s say I make an argument based on experiments that show that poodles are very intelligent.  It’s MY argument, so I get to determine its scope.  I might conclude with any of the following:

  • “Therefore, poodles are intelligent.”
  • “Therefore, dogs are intelligent.”
  • “Therefore, small dogs are intelligent.”

Let’s ignore the last one for the time being and focus on the first two.  What’s important here is that the scope that I choose determines whether or not an objection is valid.  If my conclusion is that “Dogs are intelligent,” then you can undermine it with evidence showing that Irish Setters are stupid.  But if my conclusion is “Poodles are intelligent,” then I’ve effectively warded off that objection ahead of time.  If you respond to my argument by saying that Irish Setters are stupid, I remind you that I’m only talking about poodles; your claim about Irish Setters doesn’t matter  

As the person disagreeing with me, you don’t get to determine whether or not the information you have about Irish Setters is relevant.  It’s up to me to make my argument broad enough to be vulnerable to your information (“Dogs are intelligent”) or narrow enough that your information can’t hurt it (“Poodles are intelligent.”)  And the scope of the argument is found in the conclusion.

Here’s an example of how this plays out on the LSAT, adapted from Preptest 61 (section 4; question 15).  It’s a question that was missed by one of my students who scores fairly well on practice exams (she’s consistently in the 160s):

State Senator:  My staff conducted a survey in which my constituents indicated by a 90-10 margin that they do not favor high taxes.  So residents of my state will support my bill to reduce the state income tax.

Q. The reasoning in the State Senator’s argument is most vulnerable to criticism on the grounds that the argument

(A) fails to demonstrate that the opinions of the survey participants are reflective of the opinions of the country as a whole.

(B) fails to consider that the State Senator’s constituents may not consider the state income tax to be a high tax.

(C) confuses an absence of evidence that the constituents oppose the bill with actual evidence that they support the bill.

(D) draws a conclusion that is just a restatement of one of the argument’s premises.

(E) treats a result that proves public support for the bill as one that is merely consistent with support for the bill.

 

The “beyond the scope” answer choice that she went for was (A).  The State Senator could have concluded, “Therefore, Americans will support my bill to reduce state income tax.”  If he HAD drawn that conclusion, (A) would be a great answer – the fact that residents of one state oppose the bill doesn’t mean that “Americans” (i.e. Americans in general) will support it.  

But the State Senator gets to choose the scope of his argument, which we find in the conclusion: “So (conclusion indicator word) residents of my state will support my bill…”  The State Senator has limited his argument to residents of his state, so the fact that “the country as a whole” might disagree doesn’t hurt the argument one bit.

The correct answer, by the way, is (B), but the explanation for that would fall beyond the scope (see what I did there?) of this post.

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