关于做逻辑题时候的取非的方法

切尔西

一直听到有人说取非这个方法，那位NN可以给我通俗的讲解一下么，就是这个方法一般应用在什么类题型，假设，削弱还是？然后该怎么通过取非来判断选项的正确与否，先谢谢你们了

切尔西

谢谢，不过还是没有怎么理解它的用法的，感觉每个选项取非了意思还是差不多的

465983809

一般用在求assumption型题中
取非就是说如果这个选项不成立，也就是取它的相反的意思的话，则原文的结论就不能成立。
你可以借下面的题体会一下（FeiFei逻辑 79）
Despite improvements in treatment for asthma, the death rate from this disease has doubled during the past decade from its previous rate. Two possible explanations for this increase have been offered. First, the recording of deaths due to asthma has become more widespread and accurate in the past decade than it had been previously. Second, there has been an increase in urban pollution. However, since the rate of deaths due to asthma has increased dramatically even in cities with long-standing, comprehensive medical records and with little or no urban pollution, one must instead conclude that the cause of increased deaths is the use of bronchial inhalers by asthma sufferers to relieve their symptoms.


Which one of the following is an assumption on which the argument depends?
(A) Urban pollution has not doubled in the past decade.
(B) Doctors and patients generally ignore the role of allergies in asthma.
(C) Bronchial inhalers are unsafe, even when used according to the recommended instructions.
(D) The use of bronchial inhalers aggravates other diseases that frequently occur among asthma sufferers and that often lead to fatal outcomes even when the asthma itself does not.
(E) Increased urban pollution, improved recording of asthma deaths, and the used of asthma deaths, and the use of bronchial inhalers are the only possible explanations of the increased death rate due to asthma.

自我感觉在assumption型题中经常出现 支持或加强argument 的混淆选项，如上面的A项
答案是E