题目
Karin: Every time I go to the park, I notice that there are lizards. Usually when I see one, it is a Lacerta viridis, so there are probably a large number of lizards of that species in the park.
Lina: There might be a lot of lizards of that species in the park, but your experiences don't give much evidence that there are.
Select for Supports Karin's inference the statement that, if true, most strongly supports the inference that Karin draws, and select for Supports Lina's position the statement that, if true, most strongly supports the position that Lina expresses. Make only two selections, one in each column.
选项
A.At least some of the lizards that Lina has seen in the park are of a species other than Lacerta viridis.
B.Lina knows that at least three different species of lizards inhabit the park.
C.Karin does not know how many different species of lizards inhabit the park.
D.Most of Karin's lizard sightings in the park have been observations of the same individual Lacerta viridis.
E.Karin has seen many lizards in many different parts of the park.
解析
Karin在公园里观察到蜥蜴,且通常是绿色蜥蜴(Lacerta viridis),因此他推断公园里可能有大量该种类的蜥蜴。Lina并不反驳这个推论的结论,而是对其证据提出了质疑。
**论点 (Conclusion):** 公园里有大量绿色蜥蜴。
**论据 (Premise):** Karin 经常在公园里看到绿色蜥蜴。
**攻击点 (Attack):** Lina 认为论据不足以支撑论点(即:不能因为经常看到,就推断数量很多)。
A. Lina 在公园里见过其他种类的蜥蜴。无关。Lina见过其他种类,并不能削弱她没见过绿色蜥蜴这一点,也无法攻击Karin的证据。
B. Lina 知道公园里有很多蜥蜴。无关。Lina知道整体数量多,并不能反驳她“没见过绿色蜥蜴”这一具体证据对结论的支撑作用。
C. Karin 熟悉绿色蜥蜴这个物种。无关。熟悉物种只会加强他辨认的准确性,反而可能支持Karin的观点,与Lina的质疑无关。
D. * Karin 在公园里看到的蜥蜴,大多数其实是同一只绿色蜥蜴。 正确答案(支持Lina)。如果Karin看到的只是同一只蜥蜴反复出现,那么他“经常看到”的证据就无法证明“数量很多”。这直接摧毁了论据的有效性,完美支持了Lina对证据的质疑。
E. Karin 在公园里的许多不同地方都看到了很多蜥蜴。 支持Karin,说明他看到的范围广、数量多,这增强了“公园里确实有很多”这一结论的可信度,削弱了Lina的观点。
这道题的考点在于样本有效性的识别。解题的关键在于识破 Karin 的逻辑陷阱:他把“看到的频率”等同于了“种群的数量”。选项D正是通过指出样本(看到的个体)的唯一性,打破了这一逻辑链条。