五、集体和个体/普遍和特殊之间的推导

在GRE作文的Argument Topics中还有一类常见的逻辑错误，即，将个体/特殊的特质简单地套用到集体上（以小见大），或是将集体/普遍的特质简单地套用到个体上（以大见小）。这两者本质上是同一个问题，即，错误地理解了个体/特殊和集体/普遍之间的关系，误认为个体/特殊和集体/普遍的特点一定是一致的。

以小见大的典型论述方法是举例和调查研究。例如，在论述过程中以一个当地的情况或调查研究为例，得出一个广泛的结论。在此，考生就可以质疑这一例子或调研的结果是否也适用于其他地区。

以大见小包括阐述大背景，相对于以小见大，可能更不容易理解，因为大事物的特点可能更加宽泛、多样，给人一种错觉，以为可以把很多小事物的特点放进去。但是，事实上，集体特质和个体特质之间很难画上等号，因为集体的特点可能来自于个体的加权平均，即来自于平均值，而小的特点是没有经过平均的。例如，全国范围内的男女比例是7∶6，以此推出某一个小山村的男女比例也是7∶6。这个推论是有问题的，原因很简单，全国的男女比例取的是平均值，而这个小山村里可能有特殊情况，比如大部分男人都出去打工了，那么这时，村子里的男女比例可能就不是7∶6了。

具体结合例题如下：

以小见大的情况（Day 66）

The following appeared in a memo from the owner of a chain of cheese stores located throughout the United States.

“For many years all the stores in our chain have stocked a wide variety of both domestic and imported cheeses. Last year, however, all of the five best-selling cheeses at our newest store were domestic cheddar cheeses from Wisconsin. Furthermore, a recent survey by Cheeses of the World magazine indicates an increasing preference for domestic cheeses among its subscribers. Since our company can reduce expenses by limiting inventory, the best way to improve profits in all of our stores is to discontinue stocking many of our varieties of imported cheese and concentrate primarily on domestic cheeses.”

在最新的商铺中卖得最好的cheeses来自国内，就意味着所有的商店都是如此吗？个体和集体的特质是否有可能并不一致？比如，新店铺是开设在经济水平比较低的地方，人们买不起进口的cheeses，又或者这些地区的人比较偏爱国产cheeses的口味。

以大见小的情况（Day 10）

Twenty years ago, Dr. Field, a noted anthropologist, visited the island of Tertia. Using an observation-centered approach to studying Tertian culture, he concluded from his observations that children in Tertia were reared by an entire village rather than by their own biological parents. Recently another anthropologist, Dr. Karp, visited the group of islands that includes Tertia and used the interview-centered method to study child-rearing practices. In the interviews that Dr.Karp conducted with children living in this group of islands, the children spent much more time talking about their biological parents than about other adults in the village. Dr. Karp decided that Dr. Field’s conclusion about Tertian village culture must be invalid. Some anthropologists recommend that to obtain accurate information on Tertian child-rearing practices, future research on the subject should be conducted via the interview-centered method.

Dr. Karp的研究包含但不限于Tertia这个岛屿中的孩子，这样得出的结论一定适用于Tertia这个特定的岛屿吗？集体的特质一定能够适用于个体吗？ o6MDwOhwdFMPiKmDP6BXdXbRrvMPsbvzVQR5lGYTWAXTixBs0vGsHn8W3bDnRiJC