GRE作文入门和进阶八

142.The article entitled 'Eating Iron' in last month's issue of Eating for Health reported that a recent study found a correlation¹ between high levels of iron in the diet and an increased risk of heart disease. Further， it is well established that there is a link between large amounts of red meat in the diet and heart disease， and red meat is high in iron. On the basis of the study and the well-established link between red meat and heart disease， we can conclude that the correlation between high iron levels and heart disease， then， is most probably a function of the correlation between red meat and heart disease.
　　析题：仔细读过，发现这道题有点绕，很多考生曾经有过这样的困惑：“我没有理解最后一句话的意思is most probably a function of the correlation between red meat and heart disease.是说high iron level于heart disease之间的关系是red meat与heart disease之间有关的结果那作者到底是认为high iron level和heart disease之间有没有关系阿？”再读之下，我们会发现作者其实做了一个顺接推论：red meat引起心脏病——> red meat里面还有大量的铁——> 高铁引起心脏病，就是这么一个简单的推论过程，关键认清谁推出谁，就要在审题时注意到关键的这么看似不经意却被友好的ETS“重复两次”的短语“well established”，也就是说“大量红肉与心脏病之间一定有联系”是不容质疑的论据，即本题论据是不容批驳的，关键问题在于由论据推导出结论的时候犯了“Implicit causal claims”和“gratuitous assumptions”（详细逻辑谬误分类见后文“七宗罪”），因而我们就可以以次展开攻击。很多来自网上的文章和提纲在本题上颠倒了推导对象，把“高铁引起心脏病”作为论据来推出“red meat引起心脏病”，结果导致文章失误。下面读者可通过以下范文检验一下该论证过程和思路：