请教LSAT-Set4-SecI-21

gu946

21. Whenever a major political scandal erupts before an election and voters blame the scandal on all parties about equally, virtually all incumbents, from whatever party, seeking reelection are returned to office. However, when voters blame such a scandal on only one party, incumbents from that party are likely to be defeated by challengers from other parties. The proportion of incumbents who seek reelection is high and remarkably constant from election to election.
If the voters' reactions are guided by a principle, which one of the following principles would best account for the contrast in reactions described above?
(A) Whenever one incumbent is responsible for one major political scandal and another incumbent is responsible for another, the consequences for the two incumbents should be the same.
(B) When a major political scandal is blamed on incumbents from all parties, that judgment is more accurate than any judgment that incumbents from only on party are to blame.
(C) Incumbents who are rightly blamed for a major political scandal should not seek reelection, but if they do, they should not be returned to office.
(D) Major political scandals can practically always be blamed on incumbents, but whether those incumbents should be voted out of office depends on who their challengers are.
(E) When major political scandals are less the responsibility of individual incumbents than of the parties to which they belong, whatever party was responsible must be penalized when possible.

答案是E,请问是如何推出来的?

albert

this question has been discussed before...you can find it in the summary of LSAT questions

Bensontuo

albert 发表于 2003-7-13 00:01
this question has been discussed before...you can find it in the summary of LSAT questions

I do agree your point that the question " had " been discussed before, and based on my inference of your point that op could find the details of cracking the questions withinin the summary of LSAT questions, you must imply that he should be doing his research but not re-post the same question being discussed here. However, regardless of the fact that explain of the question posted could be located, the fact itself does not overturn the right of the op to re-post the question again and to seek for extra helps. Since op have not followed up the post, since 2003 July, I must assume that he has not been getting enough support of the question posted.

So please, if you do have time to question your presume that people must be lazy due to lacking the effort of checking the " summary of LSAT questions ", you must be might as well have the same quality of your time to help people who are in need.

Bensontuo

gu946 发表于 2003-7-12 23:31
21. Whenever a major political scandal erupts before an election and voters blame the scandal on all ...

Question stem is really simple

Principle = A core argument, concept, and reasoning which must be true.

So, if the vote's reaction are guided by the " must be true core argument ", then which must be true that the core argument must not be true.

Which is, what we need to do first is to locate the core argument, and, secondly, find the necessary assumptions if the core argument must be true, and, third step, spot the negate version of that core argument.

Core argument:

P1: If A ( Scandal erupts before an election ) and B ( Voters blame the scandal on all parties equally ), then C ( all incumbents of all parties, seeking reelection are returned to office )

Inference:  If No C, then No A or No B ( or No A and No B )

P2: If B is negate ( Voters blame the scandal on only one party ), then D ( Challengers from the other parties would likely to defeat the incumbents from that party being blamed on the scandal )

Inference: 1. If No B, then D.  2. If No D, then B


* Let us combine the inferences from both 1 and 2.

If No C, then No A  - No inference

If No C, then No B, If No B, then D, So, If No C, then D

or

If No C, then No B, No A, and D

So, we have 2 version of the core argument here

If No C, then No B, No A, and No D    VS   If No C, then No B and No D


So as we know, if not all incumbent of whatever party, seeking reelection are return to office, it must be that either the major political scandal does not erupt or it does erupt and voters do not blame the scandal on all parties equally, and if voters do not blame the scandal on all parties equally to the extreme level that only one party would be blamed, then the challenger from the party without being blamed would defeat the one being blamed.

In that sense, what are the necessary assumption of the argument.

If No C, then No D must not happened: If No C, then No B, If No B then D. Which Is, IF No C, we could still have A, since we only one possibility of the argument that If No C, then No A " or " No B, and If No C, then No B, we can't be certain that If No C could guarantee No A being necessary.  In that sense, we must ensure that  IF A, then No D must not happen.

So, lets say, If No C, then D must not happen as the argument must be correct, then If A, then No D as the argument must not be happen would always be true.

For sure, the contrast of the principle asked could be describe as If No C, then No D, or If D, then C, or If A, then No D, or If D, then No A.

let us dive into the options:

A. If one is responsible for a scandal and another is responsible for another, the consequences shall be the same.

Its not about whether the consequences shall be the same or not; however, its about wether the challengers would be less likely to defeat the blamed incumbents of certain party if the scandal did happened before the reelection.

B. If B ( Voters blame all party equally ), then the judgement of blaming all party is better than the judgement of blaming only one party  - There is no any single support as to the correctness of the judgement.

C. If X ( Incumbents is rightly blamed ), then Y ( They should not seek reelection ), If No Y ( If they do ), then Z ( they should not return back to office ). Well... totally off our argument core. First of all, who should say that which incumbent should be blamed and how rightly blamed could be really evaluate ? Secondly, we only know that they will return to office if voters blamed all the parties.

D. If A, then B. But If we can determine whether should they stay in office or not, we must know their challenges.

First of all, If A, then B as the conditional logic argument has never shown in the question. Secondly, regardless of the fact that whomever the challengers should be, as long as voters only blame on the incumbents of single party, them the challengers must defeat them.

Again, its about when A happened, No D should never happened or When No C happened, No D should never happened.


E. IF A ( Scandal did erupt before the election ) and Party carries more responsibility than incumbents, that party must be penalized.

Be penalized means what ?  incumbents shall not be returned back to office, which is to say, the party those incumbents belong to should be penalized, correct ?, and the fact that party carries more responsibilities than incumbents does not mean voters would or would not blame the incumbents equally. However, If this is the case - If A - > No C, However, based on our inferences, If No C, then No A, and the contrapositive of the condition that If A - > No C is If C, then No A. Apparently, its the mistaken reversal of the necessary assumption.

What are 4 conditions mentioned we are looking for ?

If No C, then No D, or If D, then C, or If A, then No D, or If D, then No A.

Right here, its not as that complex as we figure, since If No C --> No A or No B or ( No A and No B )

Then we could say that If No C ---> A exists and No B exist. However, without A, B won't exist ( How could voters blame the incumbents for the scandal if there is no any scandal ? ) So, If No C ----> No A and No B must exist, and If that's the case, If A --- No C, and If No C, then No D ( As one of the four conditions we are looking for ), we can match our original inference that If A ---> No D must not be exist.

E is the correct answer !