Classic Flaws

Front 1

Name the Classic Flaws

Back 1

Scope Shift, Ad Hominem, Alternate Possibilities, Causation-vs-Correlation, Circular Reasoning, Equivocation, Necessity-vs-Suffieciency, Numbers-vs-percentage, Possibility-vs-certainty, Opinion-vs-Fact, Representativeness, Unwarranted Assumption

Front 2

Describe the classic flaw
SCOPE SHIFT

Back 2

When a concept appears in the conclusion that is not in the evidence.

Hint 2

LSAT Logical Reasoning sections are riddled with scope shifts - changes in focus as the author moves from evidence to conclusion.

Front 3

Describe the classic flaw ALTERNATIVE POSSIBILITIES.

Back 3

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Front 4

Describe the classic flaw
CAUSATION -vs- CORRELATION.

Back 4

Whenever you see an argument that presents two events—let’s call them X and Y– that occur together, and that then concludes that one event, X, must be causing the other event, Y, you should look for the possibility that Y in fact causes X, or that some outside factor, Z, is causing both X and Y, or it is a coincidence.

Hint 4

1) The argument concludes merely from the fact that two things are correlated that one causes the other.
2)The argument assumes a casual relationship where only a correlation has ben indicated.

Front 5

Describe the classic flaw
CIRCULAR REASONING

Back 5

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Front 6

Describe the classic flaw
EQUIVOCATION.

Back 6

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Front 7

Describe the classic flaw
NECESSITY -vs- SUFFIECIENCY.

Back 7

In order to successfully navigate the AuSable Trail, a 57-mile hiking trail fraught with unsteady terrain, one must have a pair of supportive hiking boots. Andrew recently purchased a pair of the most comfortable and supportive hiking boots on the market. Therefore, Andrew should have no trouble navigating the Ausable Trail when he goes on his hiking trip next month.

Hint 7

Now, I know we’ve seen a lot of necessary/sufficient issues in past discussions, but in flaw questions, the application is simpler. The correctly-identified flaw here would be that the argument takes a condition that is necessary for achieving the goal of completing the hike, and has treated it as though it is sufficient. Good boots are necessary; without them, Andrew couldn’t make the hike. But are they ENOUGH? What if Andrew has an awful case of the flu and can’t even get out of bed, let alone go for a 57-mile hike? The boots are not, by themselves, SUFFICIENT to ensure success on the hike. As a reader, be on the lookout for arguments that don’t differentiate between necessary and sufficient conditions.

Front 8

Describe the classic flaw
NUMBERS -vs PERCENTAGE

Back 8

Errors can be made when an author improperly equates a percentage with a definite quantity, or vice versa.

Front 9

Describe the classic flaw
POSSIBILITY -vs- CERTAINTY

Back 9

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Front 10

Describe the classic flaw
OPINION -vs FACT

Back 10

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Front 11

Describe the classic flaw
REPRESENTATIVENESS

Back 11

When author attributes a characteristic of the whole (or each member of the whole) to part of the group. OR When author attributes a characteristic of part of the group to the group as a whole or to each member of the group. OR

Hint 11

This flaw takes a small number of instances and treats those instances as if they support a broad, sweeping conclusion.Ex: "Two of my friends were shortchanged at that store. Therefore, everyone gets short changed at that store."

Front 12

Describe the classic flaw
UNWARRANTED ASSUMPTION

Back 12

Be on the lookout for disconnects between the evidence and the conclusion. Every flawed argument makes an unwarranted assumption.

Front 13

Time Shift Errors

Back 13

This flaw assumes that conditions will remain constant over time, and that what is the case in the past will be the case in the future.

Front 14

An argument is flawed when its evidence does not logically establish its ____________ (fill in)?

Back 14

Conclusion

Hint 14

Be on the lookout for disconnects between the evidence and the conclusion. Every flawed argument makes an unwarranted assumption.