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 Kmikaeli
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#17836
I am quite confused with the explanation for "Errors of Conditional Reasoning"

All I understand is that when you have a regular conditional statement A :arrow: B
the Mistaken Reversal is known as B :arrow: A and the Mistaken Negation is known as
NOT A :arrow: NOT B

I do not understand what the text on page 462 is saying in relation to these two concepts with flaw in the reasoning questions.
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 Dave Killoran
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#17838
Hi Kmikaeli ,

On page 462, those aren't complete explanations of the concepts per se, but rather ways in which LSAC has described the flaw when it occurred in prior questions. In other words, it's a description of what the author did when making that mistake.

Another way of looking at it is that the diagrams you used above are the visual representation of what is occurring when those errors are present; the text on page 462 is the written description of the error.

Thanks!
 Kmikaeli
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#17841
I do not understand why it says "the test makers must focus on the error common to both: confusing the sufficient condition with the necessary condition" This is only apparent in Mistaken Reversal so why would it include Mistaken Negation as a case that the sufficient condition is confused with the necessary condition?
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 Dave Killoran
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#17844
Hi Kmikaeli,

Actually, a Mistaken Negation involves confusing a sufficient condition with the necessary condition as well, but it "looks" different which can cause some problems.

For example, consider the following argument:

  • Premise: J :arrow: K

    Premise: J

    Conclusion: K
When the second premise is added that J, why does this then make the author think that K ? Because the author think that J is necessary, and that the lack of occurrence of the necessary will then cause the other condition (K, in this case), not to occur. Because the author thought J was necessary when it was in fact sufficient, we have the error being described there.

Another way to see this is to realize that a MR of an initial statement, and the MN of that same initial statement are actually contrapositives of each other. Meaning, therefore, that the two statements are functionally identical. For example:

  • Initial statement: C :arrow: D

    MR of that statement: D :arrow: C

    MN of that statement: C :arrow: D
Now, take a look at that MN and MR: they are contrapositives. Since a statement and its contrapositive are functionally the same, if a description applies to an MR, it also applies to the MN.

Ultimately, this allows the test makers to use the same language to describe both errors (although they tend not to).

Please let me know if that helps. Thanks!
 Kmikaeli
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#17846
Sorry for asking so many questions, but I am trying to solidify my understanding with such concepts. The last problem within the whole section pertains to Errors of Composition 'and Division. I completely do not understand this section. Also, within circular reasoning, does it basically represent a conclusion that has a premise that is almost indistinguishable and does not logically support the conclusion? For instance "I am the best at driving because I am better than all others." This basically has an argument that is circular because the premise can support the conclusion just as easily as the conclusion can support the premise. Furthermore, the premise doesn't really give logical evidence that truly supports the conclusion initially.
 Kmikaeli
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#17849
One more thing, question number 8 on page 475 clearly has a flaw which is assuming that the correlation of two things leads to a causal conclusion. I was looking for an answer choice with what that encompassed, but instead had a choice that a third event may have caused both. I am confused, because I was looking for something along the lines that states that a correlation doesn't automatically create a causal scenario.
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 Dave Killoran
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#17850
Kmikaeli wrote:Sorry for asking so many questions, but I am trying to solidify my understanding with such concepts. The last problem within the whole section pertains to Errors of Composition 'and Division. I completely do not understand this section.
This is probably easier than it looks at first glance. These errors are related, and basically revolve around thinking that the whole and the parts are basically the same (which is a problem, right? Just because it's a fun party doesn't mean that every person at the party is fun). In the case of one, the characteristic of whole is said to apply to each of the parts, and in the other, the characteristic of each of the parts is said to apply to the whole. Those forms of reasoning are often wrong, so be careful when you see that occurring.


Kmikaeli wrote:Also, within circular reasoning, does it basically represent a conclusion that has a premise that is almost indistinguishable and does not logically support the conclusion? For instance "I am the best at driving because I am better than all others." This basically has an argument that is circular because the premise can support the conclusion just as easily as the conclusion can support the premise.
Basically yes :-D


Kmikaeli wrote:One more thing, question number 8 on page 475 clearly has a flaw which is assuming that the correlation of two things leads to a causal conclusion. I was looking for an answer choice with what that encompassed, but instead had a choice that a third event may have caused both. I am confused, because I was looking for something along the lines that states that a correlation doesn't automatically create a causal scenario.
This is a good example of being close and then being confused by the options they have at their disposal. You knew that a correlation of two things doesn't necessarily allow for a causal conclusion, so you were good at that point 8-) . But, why is it that you can't draw that conclusion? There are various reasons, and one of them is the possibility that something else (including a third event that caused both) could have occurred. So, this is just an alternate way of phrasing why a correlation. doesn't automatically create a causal scenario

Thanks!
 Kmikaeli
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#17856
When I go back to the cause and effect chapter and observe the two common basic causal conclusions: one event occurring before another and two events occurring at the same time, we can state that there is a flaw in the conclusion and the possibilities of an alternate approach include a third event, a correlational relationship, and all four principle aspects mentioned on pg 253. This is a correct way to look at things right?

If this is true, then why does the flaw in the reasoning chapter not include the other three aspects that could weaken the basic causal conclusions, such as cause occurs but no effect or effect occurs but no cause, and the statistical problem in the the data used to make causal statements? Why do they not use these three aspects as possibilities of other scenarios occurring for flaw in the reasoning questions and instead stick to the 4 alternatives?

Thank you again in advance!
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 Dave Killoran
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#17861
Yes, that is a the correct way to look at it :-D

In the Flaw chapter, the ways to weaken a causal argument would not be stated in the same manner as describing the flaw. For example, bringing up that the "cause occurs but no effect" would typically weaken a causal argument, but you wouldn't state that that is the flaw in the same argument.

Does that make sense?
 Kmikaeli
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#17862
Honestly, it confused me a bit more haha. If those four options on the cause and effect chapter are flaws, why not apply them to the flaw in the reasoning questions in the same manner. Is there something different? Both expose the flaw in the conclusion and essentially weaken the argument by bringing an alternate explanation to the structure.

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