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)

　　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 feminists are not good citizens.

　　论据：Radical feminists lack family values.

　　推理依据：Family values characterize the good citizes.