标题: 请问一道LR [打印本页] 作者: chasingd2012 时间: 2012-2-15 13:54 标题: 请问一道LR Historian: We can learn about the medical history of individuals through chemical analysis of their hair. It is likely, for example, that Isaac Newton’s psychological problems were due to mercury poisoning; traces of mercury were found in his hair. Analysis is now being done on a lock of Beethoven’s hair. Although no convincing argument has shown that Beethoven ever had a venereal disease, some people hypothesize that venereal disease caused his deafness. Since mercury was commonly ingested in Beethoven’s time to treat venereal disease, if researchers find a trace of mercury in his hair, we can conclude that this hypothesis is correct. Which one of the following is an assumption on which the historian’s argument depends? (A) None of the mercury introduced into the body can be eliminated. (B) Some people in Beethoven’s time did not ingest mercury. (C) Mercury is an effective treatment for venereal disease. (D) Mercury poisoning can cause deafness in people with venereal disease. (E) Beethoven suffered from psychological problems of the same severity as Newton’s.
正确答案是B。但不太明白这个关系。而且觉得即使B成立，也不能排除Beethoven ingested mercury, but for purpose other than treating venereal.作者: simonshen 时间: 2012-2-15 22:45
这一类assumption题目可以用“否定法”，就是把某个assumption否定，如果这个assumption被否定后，原命题结论无法成立的话，那这个assumption就是一个必要的假设，也就是题目的argument所必须要depend的。 选项B如果被否定，则是“All people in Beethoven’s time ingested mercury.”即贝多芬时代所有人都注射水银。那如果贝多芬时代所有人有事没事都注射了水银的话，那就不能因为贝多芬也注射了水银而断定他是因为患了性病而要注射水银进行治疗。 还有一点要注意就是这一类assumption都是考的“必要条件”的假设，但不一定是“充分条件”。如果选项B不成立，则argument肯定不成立，但选项B成立，argument也不一定成立，正如你说的，贝多芬也可能注射水银是出于其他目的。但是这题目只要你找出一个必要条件的假设就可以了，所以不需要考虑这个条件是否充分。作者: chasingd2012 时间: 2012-2-16 10:33
了解，多谢~~！！作者: sdcar2010 时间: 2012-2-19 09:37
LZ, you did not read my posts . . .