LSAT-15-2-17 [regulation of airline industry]

pocahontas

为什么要选C呢？work to是造成导致的意思吗？C选项的意思是什么呀？不懂这个access to airport什么意思，是说去不了大城市机场吗？

我选了A，把A取非后，不正是削弱了ir的观点吗？

Consumer activist: By allowing major airlines to abandon, as they promptly did, all but their most profitable routes, the
government's decision to cease regulation of the airline industry has worked to the disadvantage of everyone who lacks access to large metropolitan airport.

Industry representative: On the contrary, where major airlines moved out, regional airlines have moved in and ,as a consequence, there are more flights into and out of most small airports now that before the change in regulatory policy.

　

17. The industry representative's argument will not provide an effective answer to the consumer activist's claim unless which one of the following is true?

(A) No small airport has fewer flights now than it did before the change in policy regarding regulation of the airline industry.

(B) When permitted to do so by changes in regulatory policy, each major airline abandoned all but large metropolitan airports.

(C) Policies that result in an increase in the number of flights to which consumers have easy access do not generally work to the disadvantage of consumers.

(D) Regional airlines charge les to fly a given route now that the major airlines charged when they flew the same route.

(E) Any policy that leads to an increase in the number of competitors in a given field works to the long-term advantage of consumers.

pocahontas

我发帖子之前都是仔细看了原来的讨论的，没有的或者还有问题的我才重新发帖子。我看了原来帖子里面都没有提到A，但是我弄不清楚，所以问一下。

lawyer_1

1。IR的推理：主要航空公司搬出的地方，地区航空公司就搬进，结果，有比政策改变前更多的航班进出多数小机场。所以，政府改变政策不利于（WORKED TO THE DISADVANTAGE OF）每个没去过大城市的人（CA的观点）这个观点是错的（ON THE CONTRARY）。

2。IR推理实质为：因为航班增加，所以没有不利于。C正好填补了这个GAP。C的意思：导致顾客较易去的航班增加的政策没有不利于顾客。

3。A的意思：没有小机场航班比以前少。是否存在小机场航班少了和IR推理没关系。

pocahontas

谢谢lawyer，你说的1，2我都看懂了！

但是关于A，A取非后是说：小机场的航班比以前要少。正是反对了IR说“航班增加”的这个前提。这样不正是用事实反对了其前提，削弱了IR的推理吗？

lawyer_1

你的将A取非问题有两个错误。

1。问题要你找IR的ASSUMPTION，A取非后能削弱IR推理并不是ASSUMPTION，能使结论不成立才算ASSUMPTION。

2。A的取非问题较复杂，较简单的才用，或者没法排除其它选项时才用。

3。A的取非为：有些小机场的航班比以前少。故实际并没削弱IR的前提：多数小机场航班增加

取非问题：

1。ASSUMPTION是结论成立的必要条件，必要条件不成立（假命题），则结论也不成立。这就是为何ASSUMPTION的正确选项取非，结论必不成立的原因。一句话，选项取非的含义就是找选项的假命题（或者叫假判断）（因为原文是假设选项是真）

2。从逻辑上讲，假命题和真命题是矛盾关系（四种对当关系中的一种）。逻辑有两种矛盾关系：全称肯定判断和特称肯定是矛盾关系，全称否定和特称肯定是矛盾关系。

以上有些概念不清楚找一本逻辑看看。

[此贴子已经被作者于2004-7-26 11:44:38编辑过]

pocahontas

懂了，thanx！