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.

这一段最明显的假定是最后一句。说话的人认为因为在贝多芬的年代，服食水银是治疗性病的方法，所以如果贝多芬身体内有水银，那就表示他患性病了。这当然是不合逻辑，除非在贝多芬的年代，只有治疗性病时身体里面才会有水银。所以没有一个答案是好的。

如果勉强要选一个，那我就会选 B。A 我也考虑过，但是那个 none 太强，和 trace 冲突。

我做这道题时也觉得没一个对的，

多谢！

agree，似乎B是最好的。

答案为D

题干逻辑线索为:

Newton头发上有水银→ mercury poisoning致psychological problems

结论说:Beethoven头发上有水银→venereal disease caused his deafness

问假设.根据三段论规则.有B→A,B→C,要成立,则有A→C.

所以答案为mercury poisoning致psychological problems →venereal disease caused his deafness的形式.

B选项明显错误.用否定代入法即可验证得出.该类形式逻辑题没有最好或者是相对好的答案,只有唯一的答案.

费费135的解释是这样的

There should be 2 assumptions to support the hypothesis. The 1st assumption of the author is that only venereal disease will be treated by mercury in Beethoven’s time. The 2nd assumption is only some people in Beethoven's time will ingest mercury, if all people ingest mercury, the evidence is not useful. So, some people in Beethoven's time did not ingest mercury. The answer should be B.

但是，

别人驳道

The explanation above is ineffective and misleading. The negate statement of choice B should be some people ingested mercury, which is irrelevant to the conclusion, rather than, the definition of assumption offered by  ETS , that the negate statement of an assumption should weaken the conclusion. As in Choice B, some people did not ingest mercury means it is possible that some people ingested mercury, and so it can not ensure Beethoven had ingested or not.

In addition, that the assumption of (X)all people did not ingested mercury will support the conclusion does not sufficient lead to (Y)some people did not ingested mercury will support the (Z)conclusion. In this case. you can not reason that X-->Y, and X->Z, then Y-->Z.

Choice A is the best answer. It correctly establishes the causal relationship that if none of the mercury introduced into the body can be eliminated and if Beethoven did ingested mercury, then the mercury would be found in the body and cause conclusive result of the chemical analysis, thus concludes the correctness of the hypothesis.