Thks NN for这道经典题目。 If A ->B (A is a condition but not necessarily a sufficient condition leading to B) is true, then its contrapositive(逆否命题) 'No B ->No A' is true, while its negation(否命题) 'No A ->No B' is not true. The reason why the negation(否命题) is false is that other possibilities leading to B are overlooked. -- by 会员 AlohaDJ (2011/8/9 0:44:53)
X:In order to reduce the amount of plastic in landfills, legislatures should impose a ban on the use of plastics for packaging goods. Y:Impossible Plastic packaging is necessary for public safety.Consumers will lose all of the safety features that plastic offers, chiefly tamper-resistant closures and shatterproof bottles.
Which of the following best describes the weak point in Y's response to X's proposal?
A. Y ignores the possibility that packaging goods in materials other than plastic might provide the same safety features that packaging in plastic offers. B. The economic disadvantages of using plastics as a means of packaging goods are not taken into consideration. C. Y attempts to shift the blame for the large amount of plastic in landfills from the users of plastic packaging to the legislators. D. Y does not consider the concern of some manufacturers that safety features spoil package appearances. E. Y wrongly assumes that X defends the interests of the manufacturers rather than the interests of the consumers.
OA: A.
Y's response to X's proposal depends on the assumption that if plastic packaging is safe, Non-plastic packaging is not safe.This reasoning is flawed as per what is mentioned in the quotes above. Choice A right points out the weakness of the flawed reasoning. |