SDCAR2010【逻辑入门】(六)Weaken
By now, I hope you have already had a better understanding of the way to identify premises and conclusions and the roles played by each sentence in an argument. In essence, main point, role, and proceed by are Must-Be-True types of questions, which do NOT allow NEW evidence. In the following posts I will talk about a few question types which allow NEW evidence.
Weaken
Common Prompts for Weakening questions:
• Which one of the following, if true, most seriously weakens the argument?
• Similar verbs: attack, call into question, cast doubt on, challenge, contradict, counter, damage, rebut, refute, undermine.
Before you look at the answers:
1. Pinpoint the main conclusion in the passage. (Read my previous Main Pointpost.)
2. Separate the premises from everything else. After you find the main point, don’t assume that all the other statements are premises; they might include opposing viewpoints, background information, and concessions.
3. Ask yourself, “Do the premises (exactly as they are stated in the passage) support the conclusion (exactly as it is stated in the passage)?” In other words, once discard everything else, how well do the premises support the conclusion? The reason you want to focus on exactly what the premises and the conclusion state is that you do not want to subconsciously make the argument better than it actually is. Do not help the author. Look at what he actually said and then decide whether his evidence stacks up:
• Does the author make any unreasonable assumptions? For example, read the following statements: “We should support the proposed law, which requires government officials to disclose their annual incomes, because it will give ordinary citizens a fair chance to keep an eye on and more control over when and how elected officials receive gifts and benefits from lobbyists.” Watch out for should, moral ethical and other loaded conclusions. The test makers like to play off commonly held assumptions about what is right or wrong in our heads. This argument unreasonably assumes that “giving ordinary citizens a fair chance to keep an eye on and more control” is good. If this is the case, the author must clearly point out this premise in his argument.
• Does the author rely on an unrepresentative survey/samples? For example, read the following statement: “Mr Xi will likely become the next President because over two-thirds of students in Fudan University said that they would vote for him.” Do these students represent fairly of the voters in the political process? Do these students even have the right to elect the next President?
• Does the author rely on a questionable analogy or comparison? For example, read the following statement: “A terrorist caught by police in Xinjiang with explosives in his backpack should first be given a warning just like a vendor without license caught by urban management officers in Beijing. First offense is not a big deal.” My God. This cannot be happening!
• Does the author’s conclusion overstate the premises? For example, read the following statements: “Acupuncture has been shown to reduce the risk of stroke. Therefore, anyone who undergoes acupuncture treatment will not experience a stroke when they are older.” Do these words sound like a TV commercial? If you are good at CR, you can have a lot of funs to pick apart commercials in Chinese or English.
