85The following appeared in the letter to an editor of a Myrian newspaper.
"Under Governor Winslow's leadership over the past four years, Myria has enjoyed unprecedented prosperity. Average wage increases this year are higher than they have been at any time since the 1970's, the number of people who report being unemployed has decreased by 10 percent, and construction of new homes is up by one third. In contrast, over the past four years Governor Winslow's opponent, Mr. Homer, has been mayor of a city in which only a small number of new businesses have opened. If Myrians want another four years like the past four years, they should reelect Governor Winslow."
AW—introduction: 1 carefully read the argument—you might want to read it over more than once 初读2遍,了解故事概要:Myria下一任市长应该选Winslow而不选Homer, 并试图用过去4年两城的发展差异来比较两人的能力高低,其中讲Myria时举了三个例子,讲另一个城市时说只有少量的新商业开展。
暂时想到的典型逻辑错误:(指一眼就看白的)
1 空间:在没交代任何背景情况下,两城不具可比性
2 内部:也不能归于一人的作为
3 时间:过去不代表将来
暂时想到的典型细节错误:report, 数字的比较等 2 identify as many of its claims, conclusions, and underlying assumptions as possible 一方面:
论据1:今年平均工资的上涨比自70年代以来任何时候都高
论据2:报告的失业人数下降了10%(注意没点明和什么时候比,注意是report)
论据3:新建房屋提高了三分之一
以上三点证明Myria空前繁荣,并将此成就归于Winslow这4年的领导; 另一方面: 论据:Homer担任市长的那个城市在过去4年中仅有少量新商业的开展(注意没有说成效怎么样)
这一点隐含的意思是Homer不给力,如果他来Myria也不会有什么作为 3 think of as many alternative explanations and counterexamples as you can 平均工资增长的他因:整体通货膨胀,或富人收入增加但穷人并没变化
失业人数下降的他因:报告缺漏,或本地就业不好而外出工作导致统计数据的变化
房屋增加1/3的他因:基数原本就很小
即使Myria市的确空前繁荣,那也不能证明Winslow能力很高。因为城市发展有过程,现在的繁荣可能因为几年前的明智决策;也可能因为Winslow身边有出谋划策的高手,而不是他一个人的功劳;也可能是上级政府对Myria更重视所以拨款多;也可能是Myria本身条件好,比如地理位置、自然资源。
同样,Homer那个市虽然变动不大,但可能它本身基础很差,有这些新商业的开展已经是很大进步了;也或者它本身发展完备,Homer很聪明的维持原有状态。
反例:Myria平均工资涨了但如果税收增加呢?房屋修建增加但环境破坏呢?或者房屋多了但其实空置没用到实处呢?(规划的失误) 4 think of what additional evidence might weaken or lend support to the claims
评价一个城市的发展,还要看医疗、教育、文化、环境、基础设施等
评价两人还应综合考察,而不只看过去4年的成绩。
并且最好是比较两人对Myria市以后4年发展的计划 5 ask yourself what changes in the argument would make the reasoning more sound (不知道这个问题和4题的区别在哪儿?求高手解答。我觉得4题想出来的那些就可以用在这儿回答)