GMAT考试：Testprep数学精解2_GMAT数学

GMAT考试：Testprep数学精解2

　　Contradiction

　　A Contradiction is committed when two opposing statements are simultaneously　asserted. For example， saying it is raining and it is not raining is a co　ntradiction. Typically， however， the arguer obscures the contradiction to the point that the argument can be quite compelling. Take， for instance， the following argument：

　　We cannot know anything， because we intuitively realize that our thoughts are unreliable.

　　This argument has an air of reasonableness to it. But intuitively realize　means to know. Thus the arguer is in essence saying that we know that we dont know anything. This is self-contradictory.

　　Equivocation

　　Equivocation is the use of a word in more than one sense during an argument.

　　This technique is often used by politicians to leave themselves an out. If someone objects to a particular statement， the politician can simply claim　the other meaning.

　　Example：

　　Individual rights must be championed by the government. It is right for one　to believe in God. So government should promote the belief in God.

　　In this argument， right is used ambiguously. In the phrase individual rights it is used in the sense of a privilege， whereas in the second sentence right is used to mean proper or moral. The questionable conclusion is possible　only if the arguer is allowed to play with the meaning of the critical word　right.