GRE写作的这些论证方法

 　　一、演绎推理论证法

　　将一个具体的事例运用到一个一般性原则从而得出结论。
　　论点:Demand for this product wii go up。
　　论据:The price of the product is sliding.
　　推理依据:Whenever prices of a product go down , demand for it rises.
　　(说明:由论据“the price of the product is sliding ”推出论点“Demand for this product will go up”,这个过程是否有效取决于推理依据“whenever prices of a product go down , demand for it rises”是否成立。下面每一种论证方法都是如此)二、定义法
　　界定一个概念的关键内涵;或者认定某个事物符合某个定义，从而得出结论。例如:
　　论点:Radical 1 feminists 2 are not good citizens.
　　论据:Radical feminists lack family values.
　　推理依据:Family values characterize the good citizes.
　　三、因果关系论证法
　　将一个判断放入一个因果关系中，指出它或者是原因，或者是结果。例如:
　　论点:The internet may be causing depression.
　　论据:When a group of people increased their use of the Internet , they felt depressed 3.
　　推理依据:There are no other reasons for the group's depression.
　　四、归纳推理论证法
　　从若干个具体事例中推出共性的一般结论。如:
　　论点:Everyone likes the movie.
　　论据:I know three people who like the movie.
　　推理依据:Three eaxmples are enough.
　　五、列举特征式论证法
　　指出某事物发生或者生存的征候或者迹象。例如:
　　论点:The child has chickenpox.
　　论据:The child has red spots.
　　推理依据:These spots are signs of chickenpox.
　　六、类比论证法
　　用我们已知的、熟悉的事物同未知的。不熟悉的事物加以比较，并用前者的情况解释者 的情况。分为三种:纵向类比(过去的事物同现在的、同一类事物的类比)、横向类比(同一 时期、同一事物之间的类比)、比喻式类比(不同类别事物之间的类比)。例如:
　　1.纵向类比(Historical analogy)
　　论点:Many people will die of SARS.
　　论据:Many people died of the Black Death.
　　推理依据:SARS and Black Death are similar.
　　2.横向类比(Literal analogy)
　　论点:China should have its fighter carriers.
　　论据:A neighboring country has a powerful carrier fleet.
　　推理依据:The two countries are similar enough to draw such a comparison.
　　3.比喻式类比(Metaphorical analogy)
　　论点:Reading a difficult book should take time.
　　论据:Digesting a large metal takes time.
　　推理依据:Reading and eating are sufficiently 4 alike to be compared.
　　七、引用权威论证法
　　引用公认的权威，或者论证自己就是权威从而对自己的观点加以论证。例如:
　　论点:China's economy will grow 8 poercent this year.
　　论据:Professors and scientists say so.
　　推理依据:These experts are reliable.
　　八、诉诸尝试法
　　利用人们的常识【包括:普遍的价值观念、人的普遍动机、生活常识】进行论证。例如:
　　1.诉诸普遍性的价值观念。
　　论点:The university curriculum should be multicultural 5.
　　论据:A multicultural curriculum will contribute to equality and acceptance.
　　推理依据:You value equality and acceptance.
　　2.诉诸普遍动机
　　论点:You should support this candidate premier 6.
　　论据:The candidate can help you get job security and safe neighbourhoods.
　　推理依据:You want job security and safe neighbourhoods.
　　3.诉诸生活常识
　　论点:She was very kind to me.
　　论据:She treated me with the best tea she had.
　　推理依据:A treatment with the best tea is an expression of kindness.
　　九、反证法
　　假设一个观点是正确的，然后却推导出荒谬的结论。例如:
　　论点:An industrious 7 man must also be thrifty 8.
　　论据:With only industry but without thrift 9 ，the person will end uo bankrupt.
　　推理依据:An industrious person ending up bankrupt sounds absurd.
　　十、统计数据论证法
　　提供数据，以资论证。例如:
　　论点:We should end the current poverty-relief program.
　　论据:It costs $45 million per year.
　　推理依据:This is too much;it proves we should end it.
　　只是一个详细的结构上的分析说明，在具体运用时，我们经常讲推理依据和论据放在了一起，但只要合理即可。论据可以自己编造，也可以是大众的例子，关键在于自己怎么样建立论点和论据之间的桥梁。上面的这些技巧，可能我们只用到某种或某几种，但我们必须得会至少一种。