ƒ❸过度推理与推理不足

在“表意”“表理”与“表情”这三个功能里，小T同学对“表意”的掌握没有任何问题，欠缺的是对“表理”和“表情”的理解。由于多年英语学习过程缺少相关训练，造成了她连续几次的GMAT失利。好不容易小T找到了自己的问题，却又从一个极端滑到另一个死胡同里，这个死胡同就是过度推理。

我们看一个GMAT例题。

例[0.5]

Tom White has often talked about running forchairman of the student council, but he has never run. However, we have justlearned that he submitted acandidacy form to the election commission. So, it is very likely that Tom willrun for the chairman this year.

Which of the following, if true, will most stronglysupport the judgment above?

（A）Tom White didn’t submit any candidacy form lastyear.

（B）The information about the candidacy form comesdirectly from the election commission.

原文翻译：

Tom White老说要竞争学生会主席但总是只说不练。最近听说他提交了正式的竞选申请，所以我们判断他这次要来真的了。

这题是一个加强题，也就是要求找出一个选项增加我对原文结论的相信程度，

（A）去年Tom没有递交申请表格。

（B）关于竞选申请的信息是直接从选举委员会那里得到的。

结果小T选择了B, 她的思维逻辑是，这个消息是官方宣布的，可信度肯定比从民间那里道听途说的靠谱，增加了整个推理的说服力。这就是典型的过度推理，在不知不觉中使用了“官方消息更靠谱”这样一种主观经验。这个主观经验，是需要防止的过度推理，因此对待B选项我们应该以减法处理掉多余的推理步骤。

而正确答案A，我们注意到选项提到的“去年没递交”这一关键信息，与原文所说的“去年没竞选”形成对照，这时候应该用加法思维将两者建立逻辑关联：由于去年没递交后来也没竞选，因此今年递交了就该竞选了。这几个信息被A选项串在了一起，加强了推理链条的强度，因此成为正确答案。

对比AB两个选项，我们分别对A采用了加，对B采用了减。很多同学的困扰在于：

——什么时候我该读出文章隐藏的信息？也就是，何时该加？

——什么时候我要避免去猜测文章以外的信息？也就是，何时该减？

答案其实就是，先用加法判断原文和选项之间的连接点在哪儿，再用减法取舍，如果在原文的逻辑推理链条中，则留下，如果在原文的逻辑推理链条外，则排除。更多内容我们后面会展开介绍。

由此可见，阅读技巧中涉及到更具体的加减法思维，简单来说，就是

（1）用减法控制思维的效率，不要让时间消耗在多余的信息读取和推理步骤之中，减法求少字，要求我们化繁为简，将多点变成一点。（2）用加法控制思维的深度，不要因为简化而漏掉关键的逻辑线索，加法求联字，要求我们化零为整，将两点变成一线。

本书的第一二两章会展开讲解这一加减法思维的具体应用。

本章练习题

从以下题目的原文部分分别读出“表意”，“表情”和“表理”的部分。特别注意那些未通过“表意”但通过“表理”方式暗示出来的内容有哪些。并回答问题。指出错误选项与原文之间加入了哪些不该有的主观经验。

（1）“Life expectancy” is the average age at death of the entire live-bornpopulation. In the middle of the nineteenth century, life expectancy in NorthAmerica was 40 years, whereas now it is nearly 80 years. Thus, in those days,people must have been considered old at an age that we now consider the primeof life.

 

Which of the following, if true, undermines theargument above?

(A) Few people who are in their forties use anyanti-aging health care products now.

(B) Most of the gains in life expectancy in thelast 150 years have come from reductions in the number of infants who die in their first year of life.

（2）Many United States companies have, unfortunately,made the search for legal protection from import competition into a major lineof work. Even when no unfair practices are alleged, the simple claim that anindustry has been injured by imports is sufficient grounds to seek relief.Contrary to the general impression, this quest forimport relief has hurt more companies than it has helped. As corporations beginto function globally, they develop an intricate web of marketing, production,and research relationships. The complexity of these relationships makes itunlikely that a system of import relief laws will meet the strategic needs ofall the units under the same parent company. Also, Internationalization increases the danger thatforeign companies will use import relief laws against the very companies thelaws were designed to protect.

 

 

The passagewarns of which of the following dangers?

 

(A) Companiesin the United States may receive no protection from imports unless theyactively seek protection from import competition.

(B) Companies that seek legal protection from importcompetition may incur legal costs that far exceed any possible gain.

(C) Companiesthat are not United States owned may seek legal protection from importcompetition under United States import relief laws.

参考答案：

（1）B。原文暗示的“表理”内容是：活到平均寿命的人被认为是老的。选项A的错误原因是：使用防衰老保养品与衰老之间不存在必然联系（减法阅读）。

（2）C。原文暗示的“表理”内容是：import relief是某种形式的import competition,让公司免收外国进口产品的竞争威胁。错误选项A加入了文章没提的activelyseek（主动申请）才能获得保护的问题，B加入了主观发散：法律成本的高低问题。