【分享】逻辑总结（3）

IORIYAGAMI

GWD逻辑思想总结
一、 总则：
1、 傻子原则：题目说了的你才知道，没说的你都不知道。不要用自己的常识给题目下任何判断。
2、 不充分原则：由选项推导题目只需要选项成为题目的必要条件而不需要其成为充分必要条件。
二、 有关与无关：（帮助你在考试时迅速排除与题目无关的选项）
有关是指选项与题目说的是一件事，即句子的主干至少有两部分相同。
注意：如果其中相同的部分有一部分是谓语，则首先考虑两种不同的状态能否共存。
三、 逻辑单题分：
1、 特殊类：对话、完成段话、句子作用
A、 对话：根据问题寻找答案
Q：一方驳斥，一方支持（如何支持与驳斥原文？）
思路：寻找原文与选项的不同点；对关键词两人是否有不同的理解；两人都说过的问题，但范围不同
Q：两人围绕何种观点进行讨论？
思路：注意第二个人的最后一句话
Q：第二人是如何驳斥第一人的？
思路：第二个人提出了第一个人没有提出的问题方向；第二人驳斥第一人的结论；第二人对第一人提出的问题做出了进一步论述，即驳斥了第一人的原因
B、 完成段话：
思路：填空中的正确选项应与题目给出的前半段有明确关联，形成一定逻辑，而同时又与后半段保持一定的一致。
2、 非特殊类：归纳与演绎
A、 归纳：由上至下的思路（即由题目到选项的解题思路）
注意：选项中不能有原文没提到的事，不能有原文中没有出现过的绝对化的概念，同时保持与原文的一致性。
B、 演绎：由下至上的思路
a、 选项与原文存在逻辑结构：支持、驳斥、评价等
思路：根据原文内容选出选项，然后进行求同（支持）、求异（驳斥），若存在相近选项则取非绝对的是正确选项。
[取非]：将选项中的话，加上谓语否定词，使其意思完全颠倒。
[取非绝对]：取非后意思绝对化
b、 解释：寻找矛盾点，正确选项中应有矛盾点的出现但不能违背原文的意思。
注意：解释的范围不能小于原文范围。
逻辑讲义
逻辑推理讲义
PART I 两大推理模式
如果我们把先发生的记作A，后发生的记作B，那么逻辑推理题的两大推理模式为：
一、“B，A”模式
逻辑推理题中有很大一部分题目是由一个Survey,record,data,study,experiment或phenomena等而得出一个结论，而这个结论往往是Survey,record,data,study,experiment,phenomena等的内容做出了一个解释。按照先发生的记作A，后发生的记作B的原则，我们把Survey,record,data,study,experiment,phenomena等记作B，而把由此得出的解释性的结论记作A。当由B得到解释性的结论A时，推理所做的hidden premise多为A是唯一的原因。换句话说，当一个推理是从一个已知的、已经发生的事实，已经存在的现象或一个研究的发现中得出一个解释性的结论时，一把暗含除了这个解释性的结论以外没有别的因素可以解释B。此类推理模式典型的引导词有：demonstrate,show,result,due to,attribute to,reason,hypothesize,the explaination is, be responsible for等。这里的A为conclusion。
另外，当推理是为达到一个目的而提出一个方法或建议的时候，推理成立暗含的假设是这个方法或建议是唯一或最具有关键性的能够实现目的的方法或建议。由于只有先实施了某一方法之后才能达到一目的，因此，按照“先发生的为A，后发生的为B”的原则，我们把目的记作B，把方法或建议记作A，这里的A为conclusion。
二、“A，B”模式
（一）当推理是由某个原因而试图得到一个结果时，推理成立的hidden premise是这个原因能够得到这个结果。由于原因一般发生在前，结果一般发生在后，因此我们把原因记作A，结果叫做B，这里的B为conclusion。（注意Because，since，for等原因引导词）。
（二）当推理时由某一条件而试图得到一个结论时，推理成立的hidden premise时该条件却能得到此结论。我们把条件叫做A，结论叫做B。（注意if，when，as long as引导条件）。
（三）当推理是由某一方法而试图达到某一目的时，推理成立的hidden premise是该方法确实能实现此目的。我们把方法叫做A，目的叫做B。注意这时并不表明A是唯一的，只是表明A是可行的。（注意By引导方法，to的不定式，in this way等引导目的）。
（四）当推理由某一个事实现象、研究的结论而试图类推（由此及彼）或外推（由过去及将来）或不完全归纳推理（由某类的部分对象推至该类的全部对象）时，推理成立的hidden premise是此与彼、过去与将来、某类的部分对象与该类的全部对象在所有属性上没有差异。我们按照“先发生的记作A，后发生的记作B”的原则，把事实、现象、研究的结论记作A，而把类推，外推或不完全归纳推理记作B。请注意此类推理与“B，A”模式的根本差异：尽管两个推理都是由一个事实、现象、研究出发，但“B，A”模式的A是对B的一个解释，说明A是导致B的原因，且暗含A是唯一的，所以A为结论：而“A，B”的B是类推、外推或进行的不完全归纳推理，且这里B是结论。
就假设（assumption）、支持（support）、反对（weaken）、评价（evaluate）这四类题型来说，把握上面两大推理模式尤为重要。因为无论是“A，B”还是“B ，A”模式，绝大多数论证都依据于hidden premise。
PART II 三大解题步骤
（一）读问题，明晰问题目的，从而迅速确定解题方向。
先读问题而不是段落似乎有为常理，但是可以实现了解题目类型。只有知道了问题目的类型，阅读段落才能更具有针对性。另外，问题目的本身的变化不多，往往一眼就能看出题型。注意：警惕选项中出现的not,unless,except,least等词，许多人由于漏看了这些小词而与正确答案无缘。
（二）读段落，根据不同的问题目的确定不同的解题重点。
如问题属于“假设、支持、反对、评价”类，读段落时重点在找出论点的前提与结论。边读边思考：从前题中能否推出结论？结论成立还需要哪些假设？
如问题属于“归纳”类，读段落时要注意其逻辑层次结构及去向。边读边琢磨：作者想要说明什么？
如问题属于“逻辑应用与技法”类，读段落时分清前提与结论。边读边考虑：段落推理犯了那种推理错误？结论的成立还需要哪些假设，假设的合理性如何等？
如问题属于“解释”类，读段落时要格外关注要解释的对象以及解释对象的特点，边读边斟酌：怎样才能找到一个与要解释的内容直接相关的答案？
（三）找答案，注意有些题型可调整看选项的顺序。
读完问题与段落之后，寻读五个选项，选出正确答案。有时阅读选项时要放慢速度，有时应该反复掂量。当然若费时过多，猜测并非下策。
逻辑问法总结
The most important key to Critical reasoning is whether you can reach the point for what the questions ask. I itemize all the questions as follows.
△加强题:
1.Which one of the following statements, if added as a premise to the argument, would make the conclusion valid / strengthen the argument?
2.Which one of the following, if true, would make the conclusion in the passage a logical conclusion?
3.Which one of the following is an additional piece of information that would support the conclusion?
4.A would be most likely to contribute to an explanation of fact 1 if which of the following were also true?
5.Which of the following, if true, could proponents of the plan above most appropriately cite as a piece of evidence for the soundness of their plan? According to this question, you should focus on the effective of plan and then find out which of the following would strengthen the effect.
6.Someone’s argument as it is presented in the passage above would be most strengthened if which of the following were true? 定位+加强
7.
△削弱题
1.Which one of the following statements, if true, most clearly undermines / seriously weaken the conclusion / argument?
2.Which one of the following assertions, if true, provides the most effective challenge to the author's conclusion?
3.Which of the following, if true, would cast the most serious doubt on the accuracy of the group’s contention. 定位+削弱
4.Which of the following, assuming that it is a realistic possibility (=if true), argues most strongly against the suggestion above.
5.Which of the following statements about something, if true, would strongly suggest that the suggestion or the plan is flawed? Suggesting something is wrong is meaning weakening.
6.Which of the following statements, if true, is the best basis for a criticism of historical costing as an economically sound pricing method for military contracts? 可以理解为对the soundness of “historical costing”的削弱，也可以理解为对a criticism of historical costing的加强。
7.Which of the following, if it were discovered, would be pertinent evidence against the speculation above? Pertinent evidence against something clearly demonstrates the effective weakening.
8.Which of the following statements, if true, provides the best evidence that someone’s reasoning is flawed?
9.The use of something could not be effective in doing something if which of the following were true?
10.Which of the following, if known, is evidence that contradicts the hypothesis stated above?
11.Which of the following, if true, could present the most serious disadvantage for AAA in doing something?
12.
△假设题
1.Which one of the following is an assumption on which the author's argument relies?
2.Which one of the following most accurately states a hidden assumption that the author must make in order to advance the argument above?
3.Which one of the following is a presupposition essential to the reasoning in the passage above?
4.The conclusion drawn in the first sentence depends on which of the following assumptions?
5.
△评价题
1.Which one of the following is the most accurate evaluation of the author's reply?
2.Which one of the following principles, if valid, justifies the author's argument?
3.Which one of the following would it be most helpful to know in order to evaluate the argument?
4.The answer to which of the following questions is least directly relevant to the union leader’s consideration of whether attempting a boycott of Gasco will lead to acceptance of their contract proposal?
5.Which of the following investigation is most likely to yield significant information that would help to evaluate the researcher’s hypothesis?
6.
△解释题
1.The author concludes that ... partly because...
2.Which one of the following, if true, argues most strongly against the explanation reported in the passage?
3.Which one of the following, if true, most helps to explain why something happens?
4.Which one of the following principles, if established, would justify the judgments about A's & B's actions?
△矛盾解决题（也可归类到解释题里）
1.Which one of the following, if true, most helps to resolve the apparent discrepancy between the two?
2.Which one of the following, if true, most helps explain the difference above?
3.Which one of the following, if true, most helps to reconcile the author's decision with the goal stated in the passage?
4.
△结论（归纳）题
1.It can be concluded from the statements above that...
2.Which one of the following statements most accurately expresses the author's main point?
3.Which one of the following statements CANNOT be true?
4.Which one of the following inferences can be most reliably drawn from the passage above?
5.The passage as a whole is structured to lead to which one of the following conclusions?
6.Which one of the following is the best statement of the primary point of the passage?
7.Each of the following can be inferred from his argument EXCEPT...
8.Which one of the following claims is central to the author's argument?
9.If the statements above are true, then which one of the following must also be true?
10.
△信息支持（反向加强--应该也可以算是归纳题）题
11.1.Which one of the following is most strongly supported by the information above?
12.The statement above, if true, best support which one of the following claim/ conclusions/which of the following assertions?
13.
△句子完成（划线填空）题—其实最好分别，就是一看到有划线的就可以判断是划线题。
1.Which one of the following is the best completion of the argument above?; Based on the passage above, which phrase does NOT provide a logical completion to the following sentence?
2.

△推理缺陷题
1.What is the flaw in the reasoning above?
2.The author's argument is logically flawed in that it...
3.The source of the man's erroneous reasoning is his...
4.The reasoning in the argument is most vulnerable to the criticism that it...
5.Which of the following indicates a flaw in the reasoning above?
6.Which of the following challenges indicates the most serious weakness in the attempted explanation described above?
7.
△逻辑相似性题
1.Which one of the following is most similar in logic to the argument above?
2.Which one of the following exhibits the same logical flaw as that exhibited above?
3.Which one of the following could be best supported by the same type of reasoning as that exhibited in the passage?
4.Which one of the following contains the error of reasoning described by the author in the passage?; Which one of the following most closely parallels the flawed pattern of reasoning in the author's reply?
5.
△逻辑相悖题
1.In which one of the following situations is the principle expressed most clearly violated?
2.
△两人争论内容题
1.The source of A & B's dispute is their lack of agreement on which one of the following terms?
2.Which one of the following is the point at issue between A & B?
3.
△逻辑策略方法题
1.Which one of the following is the best line of causal analysis for A to do?
2.The author establishes his position in the passage by doing which one of the following?
3.The author of the passage argues by...
4.The argument seeks to do which one of the following?
5.A most seriously weakens B's argument by doing which one of the following?
6.Which one of the following techniques of argument does the author use in the passage?; A's statement most closely conforms to which one of the following principles?; The relationship if A's response to B's argument is that A's response...; A responds to B's argument by...How is A's response related to B's argument?
△句子作用题（bold face）
1.In the passage above, the two portions in boldface play which of the following roles?
GMAT逻辑题型标志词总结
在面对GMAT逻辑题目的时候，第一步就是看准问题，明确题目类型，从而运用不同的技巧解题。下面我们就对各种题型的关键词做一个总结，希望可以帮助你在考场上从容面对各种问题。
　　一.归纳题
　　标志词：conclusion; inferred; implied; supported; if above true, then
it is also true。(注：support不仅仅用于归纳法。举例来说，归纳法的表达应为：
Which of the following are supported by the argument above?如果换个说法就可以
变成加强题型的表述：Which of the following support the argument above?所以在解
题的时候要格外小心。)
　　二.演绎题
　　1.第一种文章：前提推结论型
　　A.假设题：
　　标志词：assume; assumption; presuppose (特指对于前提的假设); additional
premise; not true unless; depend on; rely on.
　　B.加强题：
　　标志词：support(注意和归纳题目的区分); strengthen, conclusion can be
drawn if it were true that.
　　C.削弱题：
　　标志词：weaken; cast doubt; argue against; damage; counter; challenge;
flaw; refute; jeopardize; criticism; undermine; drawback; reasoning error;
weakness. (其中flaw，criticism，reasoning error和weakness属于名词性的削弱)。
　　D.评价题：
　　标志词：evaluate，appraisal。(根据加强题做)
　　2.第二种文章：因果结构
　　文章内部标志词：A is due to B; A is attribute to B; A is result of B;
blame B on/for A; B is responsible for
　　　A; credit A to B.
　　问题中的标志词：explanation; interpretation; hypothesis。
　　3.第三种文章：“变态结构”(表面上仍然是前提推出结论的结构，实质为因果结构，即
结论是前提的解释)。此类文章没有与众不同的标志词，需要考生在实战时分析判断。
　　从题型上看，第一类文章的线索显然多于后两类，也就是说解题上较为方便，幸运的是第一类题目一般占去了考题的绝大部分，所以说还是有技巧可寻的。
编辑:莫子　

dorbear

谢谢分享，ORIYAGAMI，感动着！

fyhllj

IORIYAGAMI, 谢谢你提供的资料，有时间，多多支持逻辑区呀！

fyhllj

同时看到你的AWA总结，真的很不错。再以此表示感谢！

jnlvo

辛苦了！

moonhawk

谢谢

jjmba

多谢!