[求助]ASSUMPTION中关于非削弱结论型的假设

A significant number of complex repair jobs carried out
by Ace Repairs have to be reworked under the company’s warranty. The reworked
jobs are invariably satisfactory. When initial repairs are inadequate,
therefore, it is not because the mechanics lack competence; rather, there is
clearly a level of focused concentration that complex repairs require that is
elicited more reliably by rework jobs than by first-time jobs.

The argument above assumes which of the following?

1. There
        is no systematic difference in membership between the group of mechanics
        who do first-time jobs and the group of those who do rework jobs.
2. There
        is no company that successfully competes with Ace Repairs for complex
        repair jobs.
3. Ace
        Repairs’ warranty is good on first-time jobs but does not cover rework
        jobs.
4. Ace
        Repairs does not in any way penalize mechanics who have worked on complex
        repair jobs that later had to be reworked.
5. There
        is no category of repair jobs in which Ace Repairs invariably carries out
        first-time jobs satisfactorily.
   

Newspaper editorial:

In an attempt to reduce the crime rate, the governor is
getting tough on criminals and making prison conditions harsher. Part of this
effort has been to deny inmates the access they formerly had to college-level
courses. However, this action is clearly counter to the governor’s ultimate
goal, since after being released form prison, inmates who had taken such
courses committed far fewer crimes overall than other inmates.

Which of the following is an assumption on which the
argument depends?

1. Not
        being able to take college-level courses while in prison is unlikely to
        deter anyone from a crime that he or she might otherwise have committed.
2. Former
        inmates are no more likely to commit crimes than are members of the
        general population.
3. The
        group of inmates who chose to take college-level courses were not already
        less likely than other inmates to commit crimes after being released.
               
4. Taking high
        school level courses in prison has less effect on an inmate’s subsequent
        behavior than taking college-level courses does.
5. The governor’s ultimate goal actually is to gain
   popularity by convincing people that something effective is being done about
   crime.

assumption 不管是supporter还是defender都可以取非削弱。

原理是，如果是supporter，那么，他原来的argument不完善，有漏洞。如果把某一个补漏的选项取非的话就把漏洞打得越开，所以削弱

如果是defender,那么他的推理已经很完善，但是因为可能有其他因素的存在，作者一般又只认为他所argue的原因是唯一原因，这时候就应该排除其他原因进行加强。相反，如果取非削弱的话，那么排除原因就变成了找出其他原因，这样的话就是他因削弱了。

你找的两道题都属于defender类型的，因为你看他们的argument都已经很完善了，没有明显的hole,那么你所要做的就是找出排除他因的答案。

取非削弱只是一个技巧，在这个技巧的背后就是上面说的原理。

第一题，作者的argument是这样的：

premise:initial works unsatisfactory

premise:The reworked jobs are invariably satisfactory

conclusion:when initial repairs are inadequate it is not because the mechanics lack competence

乍眼一看，没有什么漏洞。那你就马上想想有没有其他原因。当然有！人的因素嘛。那么作者的unstated assumption必然是两个阶段的工作人员都一样。那么正好就是A选项了（不知道你怎么说是E选项）。我们取非A选项就变成了：

There is systematic difference in membership between the group of mechanics who do first-time jobs and the group of those who do rework jobs.

你看看，是不是引入他因了。就削弱了嘛。。这就是取非削弱的意思。

同道，第2题也是。你看看是不是作者unstated assumption就是人本来没有发生变化，而是教育使得人变好了？那么正确的答案就是要帮助作者排除人的因素。你看看C 不就刚好说的是这个么。你用取非削弱看看：